\-\ New York State College of Agriculture At Cornell University Ithaca, N. Y. Library Cornell University Library S 675.T45A 1886 Farm implements and farm "ia'=*''"^^|,,^"*' 3 1924 003 362 898 Cornell University Library The original of tliis bool< is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924003362898 Farm Implements FARM MACHINERY, AND THE Principles of their Construction and Use : WITH EXPLANATIONS OF THE Laws of Motion and Force as Applied on tlie Farm. WITH OVER THREE HtTHDRED ILLUSTRATIONS BY JOHN J. THOMAS. NEW EDITION, REVISED AND ENLARGED. NEW TOEK: 0. JUDD CO., DAVID W. JUDD, Pees't, 751 BEOADWAY. 18S6. BntereB, according to Act of Congrees, in the year 1886, by DAVID W. JUDD, In the OfSce of the Librarian of Congresa, at Washington. \\y PEEFACE TO NEW AND ENLAEGED EDITION. The great improvements which have been made in recent years in the implements and machines for per- forming the work ot the farm, render it important that farmers should clearly understand the principles of me- chanical science on which they are constructed and oper- ated, that they may be used with efficiency and economy. This importance to the country at large, may be under- stood when we bear in mind that the aggregate cost of the entire equipment of all the farms in the Union, has been more than a thousand million dollars, and an equal amount is annually expended for labor in working them. As the machines are increased in number and cost, it becomes increasingly necessary that they should be used intelligently for the best success. In issuing a new edition of this work, it has been a chief aim to direct attention to the principles on which farm tools and machines are operated, that the farmer may know the reasons for success or failure, and not be guided by random guessing. This knowledge enables him to select intelligently in the purchase of tools and machines. The latest improvements are described in the chapter on " Eecent Machines ; " while a thorough revision has been made of the rest of the work, bringing the whole up to the present date. J. J. Thomas. UifiON' Spbings, February, 1886. (3) CONTENTS.. PART I.— MECHANICS. CHAPTER I. — Introduction. — Value of Farm Machinery— Im- portance of a Knowledge of Mechanical Principles 7-10 CHAPTER II. — General Principles of Mechanics. — Inertia, Experiments and Examples — Inertia of Moving Bodies, or Momentum — Fast Riding — The Tiger's Leap — Pile Engines — Fly-wheel — Estimating the Quantity of Momentum — Compound Motion — Various Examples — Centrifugal Force. 10-23 CHAPTER III.— Attraction.— Gravitotion— Velocity of Falling Bodies — Resistance of the Air — Coin and Feather — Galileo's Famous Experiment — Cohesion— Soils — Strength of Ma- terials — Capillary Attraction — The Earth a Desert without it— The Ascent of Sap — Centre of Gravity — Experiments — Upsetting Loads — Shouldering Bags — Rocking Bodies 33-i2 CHAPTER IV.— Simple Machines, or Mechanical Powers.— Law of Virtual Velocities — The Lever— Many Examples of Levers — Estimating the Power of Levers — Three-horse Whiffle-tree — Compound Levers— Weighing Machines — Stump Pullers— A Wild Theory— Wheel and Axle— Examples— Band and Cog-work— The Pulley — Packer's Stone Lifter — The Inclined Plane— Crooked Roads — Power of Locomotives — Good and Bad Roads — The Wedge — The Screw — Knee-joint Power— Lever Washing Machines — Cheese Presses — Rolling Mills — Straw Cutters 42-74 CHAPTER V. — Applioation of Mechanical Principles in the Structure of Implements and Machines— Various Examples — Calculating the Strength of Parts 75-81 CHAPTER VI.— Friction.— How to ascertain its Amount- Friction on Roads — Resistance of Mud — The Resnlts of the Dynamometer — Width of Wheels — Velocity — Size of Wheels on Roads — Friction Wheels — Lubricating Sub- stances—Friction Necessary to Existence 81-93 CHAPTER VTI.— Principles of Draught.— Applied to Wagons — To Plows — Combined Draught of Animals — WhifiBe-trees for Three Horses — Potter's do. — Wier's Single-tree — The Dynamometer — Self-registering do.— Waterman's do. — Dynamometer for Rotary Motion 93-108 4 COKTEIfTS. V CHAPTER Vni —Application of Labor.— Power of Horses— Of Men -Best Way to Apply Strength 108-113 CHAPTER IX — Models of Machines. — Common Blunders — Works of Creation Free from Mistakes 113-115 CHAPTER X. — CoNSTKUOTiON AND Use or Farm Implemekts AND Machines— Implements of Tillage. — Importance of Simplicity — Plows — ^Rude Specimens — Cast-iron and Steel do.— Character of a Good Plow — The Cutting Edge — Mould-board — Easy Running Plows — Crested Furrow Slices — Lapping and Flat Furrows — How to Plow Well — Fast and Slow Plowing — The Double Michigan — The Sub- soil Plow — The Paring Plow — Gang Plow — Ditching Plow — Mole Plow — Coulters — Weed Hook and Chain — Pdlver- IZBRS— Harrows — Geddes' Harrows— Scotch do.— Morgan Harrow — Norwegian de. — Shares' do. — Cultivators — Hol- brook's- Alden's — Garrett's Horse-hoe — Two-horse Culti- vators — Sulky do. — Comstock's Spader— Clod Crushers- RoUer 115-153 CHAPTER XI.— SowiNO Machines.- Wheat Drills— Bickford and Hoffman's do. — Seymour's Broadcast Sower- Com Planters— True's Potato Planter— Hand Drills 153-157 CHAPTER XII. — Maohines for Hating and Harvesting.— Mowing and Reaping Machines— Cutter-bar — Combined Machines — Self Rakers— Johnson's do. — Marsh's and Kirby's do.— Dropper— Binders— Marsh's Harvester— Dura- bility and Selection of Machines— Hay Tedders— Bullard's ao.— American do.— Horse Rakes— Revolving do.— Sulky Revolvers— Warner's do.— Spring Tooth Rakes— Hollings- ■worth's do.— Hay Sweep— Horse Forks— Glad ding's do.— Palmer's, Myers', Beardsley's, Raymond's— Harpoon Forks —Hay Carriers— Hicks' do.— Building Stacks — Palmer's Hay Stacker— Raymond's Hay Stacker— Dederick's Hay Press— Beater do.— Hay Loaders 158-186 CHAPTER XIII.— Thrashing, Grinding, and Preparing Products. — "Value of Thrashing Machines — Endless Chain Power— How to Measure Power of— Churning by Tread Power— Pitt's Elevator— Com Shellers-Burralls', Richards'— Root Washer — Root Slicers — Farm Mills, Allen's, Forsman's— Emery Cotton Gin 186 197 PART II.-MACHINERT IN CONNECTION WITH WATER. CHAPTER I.— Hydrostatics.— Upward Pressure— Measuring Pressure— Calculating Strength of Tubes, etc.— Artesian Wells— Determining Pressure in Vessels- A Puzzle Ex- plained—Hydrostatic Bellows— Press— Specific Gravities- Table of do —Weight and Bulk of a Ton of DiflFereut Sub- stances 198-210 VI CONTENTS. CHAPTER II.— HTDBAnLios.— VeWcity of Water— Discharge of Water through Pipes — Velocity in Ditches — Leveling Ditches — Archimedean Screw-pumps — For Cisterns — Non- freezing do. — For J)eep Wells— Drive Pumps — Chain Pumps — Rotary do. — Suction and Forcing Pump — Turbine Water Wheels — The Water Kam— Water Engines for Gardens— Flash Wheel— Nature of Waves— Size of do. — Preventing Inroads by do. — Cisterns — To Determine Con- tents of 311-238 PART III.— MACHINERY IN CONNECTION WITH AIR. CHAPTER I. — Peesshbe of Aie. — Weight of the Atmosphere — Hand Fastened by Air — Barometer — Measuring Heights- Syphon 839-245 CHAPTER II.— Motion of Aib.— Winds — Wind-mills, how Used— Brown's do. — Causes of Wind — Chimney Currents — Construction of Chimneys— To Cure Smoky do. — Chimney Caps — Ventilation 245-359 PART IV.— HEAT. CHAPTER I. — Conducting Power — Expansion, Great Force of — Experiments with — Steam Engine— do. for Farms — Steam Plows— Latent Heat — Green and Dry Wood 260-276 CHAPTER IV. — Radiation.— Several Examples in Domestic Economy — Dew and Frost— Frost in Valleys— Sites for Fruit Orchards 276-280 PART v.— RECENT MACHINES. Improvement in Plows.— Hard or Chilled Iron Plows— Sulky Plows — Spring-tooth Harrow — Disc Harrow — Thomas Smoothing Harrow— Corn-Planters— Mowers and Reapers — Hay Loaders— Corn Huskers- Hay Presses — Wind- ™™s 281-289 APPENDIX. Apparatus for Experiments 391-S93 Discharge of Water through Pipes '..'.'...'.... 294 Velocity of Water in Pipes 094 Rule for Discharge of Water ! !295-29S Velocity of Water in Tile Drains ggg <^i°^^»'y .'.".'.■.■.'.■;;;; :;297-306 FARM IMPLEMENTS AND FARM MACHINERY. PART I. MECHANICS. CHAPTER I. INTRODUCTION. N'o farm can be well furnished without a large number of machines and implements. Scarcely any labor is per- formed without their assistance, from the simple opera- tions of hoeing and spading, to the more complex work of turning the sod and driving the thrashing-machine. The more perfect this machinery, and the better fitted to Its work, the greater wiU be the gain derived by the farm- er from its use. It becomes, therefore, a matter of vital importance to be able to construct the best, or to select the best already constructed, and to apply the forces re- quired for the use of such machines to the greatest possi- ble advantage. 7 8 MECHANICS. Nothing shows the advancement of modem agriculture in a more striking light than the rapid improvement in farm implements. It has enabled the farmer within the last fifty years to effect several times the work with an equal force of horses and men. Plows turn up the soil deeper, more evenly and perfectly, and with greater ease of draught; hoes and spades have become lighter and more efficient ; grain, instead of being beaten out by the slow and laborious work of the flail, is now showered in torrents from the ibrashing-machine ; horse-rakes accom- plish singly the work of many men using the old hand- rake ; horse-forks convey hay to the barn or stack with ease and rapidity ; twelve acres of ripe grain are neatly cut in one day with a two-horse reaper; grain drills and planting machines, avoiding the tiresome drudgery of hand labor, distribute the seed for the future crop with even- ness and precision. The owner of a seventy-thousand-acre farm in Illinois carries on nearly all his work by labor-saving machinery. He drives posts by horse-power; breaks his ground with Comstock's rotary spader; mows, rakes, loads, unloads, and stacks his hay by horse-power ; cultivates his corn with two-horse, seated or sulky cultivators ; ditches low ground, sows and plants by machinery; so that his labor- ers ride in the performance of their tasks without exhaust- ing their strength with needless walking over extended fields. The great value of improved farm machinery to the country at large has been lately proved by the introduc- tion of the reaper. Careful estimate determined that the number of reaping machines introduced througliout the sountry up to the beginning of the gi-eat rebellion, per- formed an amount of labor while working in harvest nearly equal to a million of men with hand implements. The reaper thus filled the void caused by the demand on workingmen for the army. An earlier occurrence of that VALUE OF FARM MACHINEET. 9 war must therefore have resulted in the general ruin of the grain interest, and prevented the annual shipment of the millions during that gigantic contest, which so greatly surprised the commercial savans of Europe. The implements and machines which every farmer must have who does his work well are numerous and often costly. A farm of one hundred acres requires the aid of nearly all the following; two or more good plows, a shovel-plow, a small plow, a subsoiler, a single and two- horse cultivator, a seed-planter, a grain-drill, a roller, a harrow, a fanning-mill, a straw-cutter, a root-slicer, a farm wngon with hay-rack, an ox-cart, a horse-cart, wheel-bar- row, sled, shovels, spades, hoes, hay-forks and manure- forks, hand-rakes and horse-rakes, scythes and grain- cradle, grain-shovel, maul and wedges, pick, axes, wood- saw, hay-knife, apple-1 bidders, and many other smaller con- veniences. The capital for furnishing the farms in the Union has been computed to amount to more than five hundred millions of dollars, and as much more is esdinat- ed to be yearly paid for the labor of men and horses throughout the country at large. To increase the effect- ive force of labor only one-fifth would, therefoi'e, add an- nually one hundred millions in the aggregate to the profits of farming. A knowledge of the science of mechanics is not so well understood among all classes of people as it should be. A loss often occurs from the want of a correct knowledge of mechanical principles. The strength of laborers is badly applied by the use of unsuitable tools, and that of teams is partly lost by being ill adjusted to the best line of draught. We may perhaps see but few instances of so great a blunder as the ignorant teamster committed who fastened his smaller horse to the shorter end of the whifiie-tree, to balance the large horse at the longer end ; yet instances are not uncommon where operations are per- formed to almost as great a disadvantage, and which, to 1* 10 MECHANICS. a person well versed in the science of mechanics, would appear nearly as absurd. It is well worth while to look at the achievements made through a knowledge of mechanical principles. Compare the condition of barbarous and savage tribes with that of modem civilized nations. The former, scattered in com- fortless hovels, subsist by precarious hunting, or on scanty crops raised on patches of ground by means of the rudest tools. The latter are blessed with smooth, cultivated fields, green meadows, and golden harvests. Commerce with its hum of business, extending through populous cities, and along a hundred far-stretching lines of rail-ways, scat- ters comforts and luxuries to millions of homes ; while ships for foreign commerce thread every channel and whiten every sea. The contrast exhibits the difference between ignorance on the one hand, and the successful application of scientific principles on the other. It is our present object to point out to the farmer the advantages which would result from a wide extension, through all classes, of this knowledge, that the opportunities may be continually increased for general improvement. CHAPTER II. GENERAL PRINCIPLES OF MECHANICS. Having briefly pointed ou.t some of the advantages to the farmer of understanding the principles of the ma- chines he constantly uses, we now proceed to an examina- tion of these principles. It will be most convenient to begin with the simpler truths of the science, proceeding, as we advance, to their application in the construction of machines. INERTIA. — EXPERIMENTS AND EXAKPLES. 11 INERTIA. An important quality of all material bodies is inertia. This term expresses their passive state — that is, that no body (not having life), when at rest, can move itself, nor, "when in motion, can stop itself. A stone has not power to commence rolling of its own accord ; a carriage can not tr.avel on the road without being drawn ; a train of cars never commences gliding upon the rails without the power of the locomotive. On the contrary, a body, when once set in motion, will continue in motion perpetually, unless stopped by some- thing else. A cannon ball rolled upon the ground moves on until its force is gradually overcome by the. resistance of the rough earth. If a polished metallic globe were driven swiftly on a level and polished metallic plane, it would Fig. 1. contirme in motion a long time and travel to a great distance ; but still the extremely minute roughness of the surfaces, with the resistance of the air, would continually diminish its speed until finally stopped. A wheel made to spin on its axis revolves un- til the friction at the axis and the impeding force of the air bring it to rest. But if the air is first removed, sremivinginavacuum. '^y means of an air-pump, the mo- tion will continue much longer. Under a glass receiver, thus exhausted, a tcp has been made to spin for hours, and a pendulum to vibrate for a day. The resistance of the air may be easily perceived by first striking the edge and then the broad side of a large piece of pasteboard against the air of a room. It is further shown by means of an interesting experiment with the air-pump. Two fan-wheels, made of sheet tin, one, a, striking the air with its edges, and the other, b, with its broad faces (fig. Fanst 12 MECHANICS. 1), are set in motion alike; b is soon brought to rfist, while a continues revolving a long time. If now they are placed under the receiver of an air-pump, the air exhaust- ed, and motion given to them alike by the rack-work d, they will both continue in motion duiing the same period. There is no machinery made by man free from the checking influence of friction and the air; and for this reason, no artificial means have ever devised a perpetual motion by mechanical force. But we are not without a proof that motion will continue without ceasing when nothing operates against it. The revolutions of the planets in their orbits furnish a sublime instance; where removed from all obstructions, these vast globes wlieel nrotmd in their immense orbits, through successive centuiies, and with unerring regularity, preserving undiminished the mighty force given them when first launched into the re- gions of space. To set any body in motion, a force is requisite, and the heavier the body, the greater must be the force. A small stone is more easily thrown by the hand than a cannon ball ; speed is more readily given to a skiif than to a large and heavy vessel ; but the same force which sets a body in motion is re- ^C quired to stop it. Thus a wheel or a grindstone, made to revolve rapidly, would need as great an effort of the arm to stop it suddenly as to give it in^tia Apraratus. ^^^^^ '"ot^^"- ^° """sual exertion of the team is necessary in starting a loaded wagon; but when once on its way, it would require the same effort of the horses to stop it as to back it when at rest. The force of inertia is finely exhibited by means of a little instrument called the inertia apparatus (fig. 2). A marble or small ball is placed on a card, c, resting on a concave stand. A spring snap is then made to strike the INERTIA. — EXPERIMENTS AND ES A-MVI EB 13 card, throwing it to a distance, but leaving the ball upon the hollow end of the stand. The same experiment may be easily performed by placing a very small apple or other solid on a card, the whole vesting on a common sand-box, or even the hollow of the hand. A sud- pj^ 3 den snap with the finger will throw the card away, while the apple will drop into the cavity. The following experiment is still more striking : Procure a thread just strong enough to bear three pounds, and hang upon it a weight of two pounds and a half. Another half pound Avould break it. Now tie another thread, strong enough to bear one pound, to the lower hook of the weight. If the lower thread be pulled gradually, the upper thread will of course break ; but if it be pulled with a jeric, the lower thread will break. If the jerk be very sudden, the iower string will break, even it be considerably stronger than the upper, the in- ertia of the weight requiring a great force to overcome it suddenly. The threads used in this experiment may be easily had of any desired strength by taking the finest sewing cotton, and doubling to any desired extent. This experiment shows the reason why a horse, when he suddenly starts with a loaded wagon, is in danger of breaking the harness ; and why a heavier weight may be ' lifted with a windlass or pulley having a weak rope, if the strain is gradual and not sudden. For the same reason, glass vessels full of water are sometimes broken when hastily lifted by the handle. When a bullet is fired through a pane of glass, the inertia retains the surrounding glass in its place during the moment the ball is passing, and a round' hole only is made; while a body moving more slowly, and pressing the glass for a longer space of time, fractures the whole pane. 14 MECHANlCa. INEETIA OF MOVING BODIES, OE MOMENTtTM. Momentum is the inertia of a moving body. When a force is applied to a heavy body, its motion is at first slow ; but the little momentum it thus acquires, added to the ap- plied force, increases the velocity. This increase of velocity is of course attended with increased momentum, which again, added to the acting force, still further quickens the speed. For this reason, wlieii a steam-boat leaves the piei-, and its paddle-wheels commence tearing through the wa- ter, the motion, at first slow, is constantly acculerated un- til the increasing resistance of the water becomes equal to the strength of the engine and the momentum.* Were it not for the momentum of moving bodies (inertia exist- ing), no speed ever could be given to any heavy body, as a carriage, boat, or train of cars. The chief danger in fast riding, or fast traveling of any kind, is from the momentum given to the traveler. If a rail-way passenger shonld step from a car when in full mo- tion, he would strike the earth with the same velocity as that of the train; or if the train at thirty miles an hour should be instantly stopped, the passengers would be pitched forward with a swiftness equal to thirty miles an hour. When a horse suddenly stops, the momentum of the rider tends to throw him over the horse's head. When a wagon strikes an obstruction, the driver falls forward. A case in court was once decided against the plaintiflf, who claimed that the defendant had driven against his wavater can not enter until it is broken up EARTH A DESEET WITHOUT CAPILLARY ATTRACTION. 33 r pulverized. It is for this reason that subsoil plowing ecomes so eminently beneficial, by deepening the mellow ortion, and thus affording a larger reservoir, which acts ke a sponge in holding the excess of falling rains, until 'anted in the dry season. For the same reason, a well- altivated soil is found to preserve its moisture much bet- jr during the heat of summer than a hardened and neg- scted surface. If capillary attraction should cease to exist, the earth rould soon become a barren and uninhabitable waste, 'he moisture of rains could not be retained by the parti- les of the soil, but would immediately sink ir down into the earth, leaving the surface t all times as dry and unproductive as a esert ; vegetation would cease ; brooks and ivers would lose the gradual supplies which be earth affords them through this influence, nd become dried up ; and all plants and all nimals die for want of drink and nourish- lent. Thus the very existence of the whole uman race evidently depends on a law, ap- arently insignificant to the unthinking, but ointing the observing mind to a striking roof of the creati\e design which planned all the works f nature, and fitted them with the utmost exactness for he life and comfort of man. ASCENT OF SAP. The following interesting experiments serve to explain le cause of the ascent of sap in plants and trees : Take a small bladder, or bag made of any similar sub- tance, and fasten it tightly on a tube open at both ends Sg. 17) ; then fill them with alcohol up to the point C, nd immerse the bladder into a vessel of water. The al- ohol will immediately rise slowly in the tube, and if not 2* 34 MECHANICS. more than two or three feet high, •will run over the top. This is owing to the capillary .attraction i:i the minute pores of the bladder, drawing the water within it faster than the same attraction draws the alcohol outward. One liquid will thus intrude itself into another wilh great force. A bladder filled with alcohol, with its neck tightly tied, will soon burst if plunged under water. If a blad- der is filled with gum-water, and then immersed as before, the water will find its way within against a very heavy pressure. In this manner sap ascends through the minute tubes in the body of trees. The sap is thickened like gum-water when it reaches tlie leaves, and a fresh supply, therefore, enters through the pores in the spongelets of the roots by capillary attraction, and, rising through the stem, keeps up a constant supply for the wants of the growing tree. CENTKE OF GRAVITY. The centre of gravity is that point in every hard sub- stance or body, on every side of which the different parts exactly balance each other. If the body be a globe or round ball, the centre of gravity will be exactly at the centre of the globe ; if it be a rod of equal size, it will be at the middle of the rod. If a stone or any other sub- stance rest on a point directly under the centre of gravity, it will remain balanced on this point ; but if the point be not under the centre of gravity, the stone will fall toward the heaviest side. Some curious experiments are performed by an ingenious management of the centre of gravity. A light cylinder of cork or pasteboard contains a concealed piece of lead 9 (fig- 18).' The lead, being heavier than the rest, will CENTRE OF GBAVITY. EXBERIMENTS. 35 Fig. 19. Body singularbj batanceA by lead knobs. luse the cylinder to roll up an inclined plane, when laced as shown by the lower figure on the preceding en- raving, until it makes half a revolu- on and reaches the place of the up- er figure, when it will remain sta- onary. If a curved body, as shown I fig. 19, be loaded heavily at its nds, it will rest on the stand, and resent a singular appearance by not illing, the centre of gravity lying etween the two heavy portions on ie end of the stand. A light stick f some length may be made to stand Q the end of the finger, by sticking 1 two penknives, so as to bring the entre of gravity as low as tlie finger-end (fig. 20). If any body, of whatever shape, be suspended by a Fig. 20. hook or loop at its top, it will necessarily hang so that the centre of gravity shall be di- rectly under the hook. In this way the centre in any substance, no matter how irregular its shape may be, is ascertained. Sup- pose, for instance, we have the irregular plate or board shown in the annexed iig. 21. figure (fig. 21) : first hang it by the hook a, and tf( the centre of gravity will be somewhere in he dotted line a b. Then hang it by the hook c, and it dll be somewhere in the line c d. Now the point e, where liey cross each other, is the only point in both, conse- '^entre of gravity maintained by tiro ppiilcnives. 36 MECHANICS. quently this is the centre sought. If the mass or body, instead of being flat like a board, be shapeless like a stone or lump of chalk, holes bored from difFei-ent suspending points directly downward will all cross each other exactly at the centre of gravity. LINE OF DIKKCTION. An imaginary line from the centre of gravity perpendic ularly downward to where the body rests is called the line of direction. Now Iti any solid body whatever, whether it be a wall, a stack of grain, or a loaded wagon, the line of direction must fall within the base or part resting upon the ground, or it will immediately be Fig. 22. Fig. 83. Centre of gravUij an level and inclined roads. thrown over by its own weight. A heavily and even- ly loaded w.igon on a level road will be perfectly safe, be- cause tlie line of directum fal's equally between the wheels, as shown in fig. 22, by the dotted line, c, being the centre. But if it pass a steep side- hill road, throwing this line outside the wheels, as in fig. 23, it must be instantly overturned. If, however, instead of the high lo'ad represented in the figure, it be some very heavy material, as brick or sand, so as not to be higher than the square box, the centre will be much lower down, or at b, and thus, the line fiilling within the wheels, the load will be safe from upsetting, unless the upper «_heel pa=s over a stone, or tlie lower wheel sink into a rut. The centre of gravity of a Inrge load may be nearly ascer- tained by measuring with a rod ; and it may sometimes happen that by measuring the sideling slope of a road, all of which may be done in a few minutes, a teamster may save himself from a comfortless upsetting, and perhaps CENTRE OP GEAVmr. — LOADING AVAGONS. 37 leavy loss. Again, a load may be temporarily placed so auch toward one side, while passing a sideling road, aa o throw the line of direction considerably more up hill han usual, and save the load, which may be adjusted igain as soon as the dangerous point is passed. This irinciple also shows the reason why it is safer to place only ight bundles of merchandise on the top of a stage-coach, yhile all heavier articles are to be down near the wheels ; md why a sleigh will be less likely to upset in a suow- irift, if all the passengers will sit or lie on the bottom. SVhen it becomes necessary Fig. 24. Fig. 25. fan evtn and one-sided o build very large loads )f hay, straw, wool, or •ther light substances, the ' reach," or the long con- lecting-bar of the wagon, ttust be made longer, so as Q increase the length of the cmtre ofgravUy of a oad ; for, by doubling the '°'^' ength, two tons may be piled upon the wagon with as luch security from upsetting as one ton only on a short ragon. Where, however, a high load can not be avoided, great are must be taken to have it evenly placed. If, for in- tance, the load of hay represented by fig. 24 be skillfully uilt, the line of direction will fall equally distant within ach wheel ; but a slight misplacement, as in fig. 25, will alter this line as to render it dangerous to drive except n a very even road. Thus eveiy one who drives a wagon should understand i»e laws of nature sufficiently to know how to arrange tie load he carries. It is true that experience and good udgment alone will be sufficient in many cases ; but no erson can fail to judge better, with the reasons clearly, ccurately, distinctly before his eyes, than by loose con- ecture and random guessing. 38 MECHANICS. 9'-"'T' "7 A '^ / \ I / \ ' <*■■ \ Every farmer who erects a wall or building, every team- Bter who drives a heavy load, or even he who only carries a heavy weight upon his shonlder, may learn something use- ful by understanding the laws of gravity. It is familiar to every one, that a body resting upon a broad base is more difficult to upset than when the base Fig, 25. is narrow. For instance, the square block (fig. 26) is less easily thrown over than the tall and narrow block of equal weight, because, in turning the square block over its lower edge, the centre of gravity must be lifted up considerably in the curve shown by the dotted line c ; but with a tall, narrow block, this curve being almost on a level, very little lifting is re- quired. Hence the reason that a high load on a wagon is so much more easily overturned than a low one. Of all forms, a pyramid stands the most firmly on its base. The centre of gravity, c (fig. 26), being so near the broad bottom, it must be elevated in a very steep curve to throw the line of direction beyond the base. For this reason, a stone wall, or the dam for a stream, will stand better when broad at bottom and tap^iag- to. a narrow top than if of equal thickness throughtfjit-. ^'' * '••'' ^-^ "When a globe or round ball is placed upon, a smooth floor, it rests on a single point. If the floor be level, the line of direction will fall exactly at this rcsting-point (fig. 27). To move the ball, the centre will move precisely on a level, without be- ing raised at all. This is the reason that a ball, a cylinder, or a wheel is rolled forward so much more easily than a flat-sided or irregular body. In all these cases, the line of direction, although constantly Fife. 27. CENTRE OF GRAVITY. EXAMPLES. 39 hanging its place, still continues to fall on the very point in which the round body rests. But if the level floor is exchanged for a slope or inelin- d plane (fig. 28), the line of direc^ Fig as. ion no longer falls at the touching- loint, but on the side from it dowu- vard ; the ball will therefore, by its nere weight, commence rolling, and iontinne to do so until it reaches the )ottom of the slope. Wlieel-carriages owe their comparative ease of draught o the fact that the centre of gravity in the load is moved brward by the rolling of the wheels, on a level, or paral- el with the surface of the road, just in the same way that he round ball rolls so easily. Each wheel supporting its »art of the load at the hub, the same rule applies to each ,s to a ball or cylinder alone. Hence, on a level road, the Lne of direction falls precisely where the wiieels rest on he ground, but if the road ascend or descend, it falls else- where ; this explains the reason why it will I'un by its own reight down a slope. Wbeaeyer a stone or other obstruction occurs in a road, it becomes requisite to raise the centre by the force of the team and by means of oblique motion, so as to throw the wheel over it, as shown by fig. 29. One of the reasons thus becomes very* plain why a large wheel will un with more ease on a rough road than a smaller one ; he larger one mounting any. stone or obstruction without ifting the load so much out of a level or direct line, as ihown by the dotted lines in the aimexed figures, (figs. 29 Fig. 30 40 MECHANICS. and 30). Another reason is, the large wheel does not sink into the smaller cavities in the road. A self-supporting fniit-ladder (fig. 31) (the centre of gravity, when in use, being at or near the top) must have its legs more widely rig- 31- F'e- 33- spread, to be secure from falling, than if the centre were lower down. Hence such a position, as in fig. 32, would be unsafe. The support of the human body, in standing and walking, exiiibits some interesting exam- ples in relation to this subject. A child can not learn to walk until he acquires skill enough to keep his feet always in the line of direc- tion. When he fails to do this, he topples over toward tlie side where the line falls outside his feet. A man stand- ing with his heels touching the wash-board of a room can not possibly stoop over without falling, because, when he A dangerrrtis- A JtrnhrTctfrmt-lcuiAcr. '■y-"'' Z™"- • ladder. Fig. 33. bends, the line of direction falls forward of his toe>!, the wall against which he stands preventing the movement of his body backward to preserve the balance. In walking, the centre rises and falls slightly at each step, as shown by the waved line in fig. 33. If it were not for the bending of the knee-joints, this exercise would be much more laborious, as it would then become needful to throw the centre into an upward curve at eveiy step. For this reason, a wooden leg is more imperfect than the natural one (fig. 34). Hence the reason why walking on crutches is laborious and fatiguing, because at every on- CENTKE OF GRAVITY. — EXAMPLES. 41 Fig. 36. d Step the body must be thrown upward in a curve, a wagon mounting repeated obstructions. 7'hen a load is carried on the shoulder, it should be so ed that the line of direction mny pass directly through the shoulder or back down to the feet, fig. 35. An unskillful person will sometimes place a bag of grain as shown in fig. 36. The line falling outside his feet, he is compelled to draw downward with great force on the other end of the bag. A man who. iei a heavy pole on his shoulder should seo that the ;re is directly over his shoulder, otherwise he will be pelled to bear down upon the lighter end, and thus in an equal degree to the weight upon his body, an elliptical or oval body, fig. 37, rest upon its side )lling It ill either direction elevates Fig. 37. centre, c, because it is nearest the on which the body rests. If, in raised, it be suffered to fall, its nentum carries it beyond the it of rest, and thus it continues :ing until the force is spent. The •se of the centre during these mo- s is shown by the curved dotted c. If it be placed upon end, as in fig. 38, then nny toward either side brings the centre of gravity nearer the touching-point, that is, causes it to descend, and the body consequently falls over on its side. This may be easily illustrated with an egg, which will lie at rest upon its side, but falls when set on either end. The rockers of chairs, cradles, • and cribs, are formed on the princi- just explained. If so made that the centre of gravity ion Fig. 38. 42 MECHANICS. of the chair or cradle is nearer the middle of the rocker than to the ends, the rocking motion will take place; and when the distance from the centre of gravity to the ends „. „„ _. .„ of the rockers is but little greater r Ig. 09. rig. 4U. "-^ than the distance to the middle, c, A as in fig. 39, the motion will be; slow and gentle ; but if this differ- ence be greater, as in fig. 40, it will Ja be rapid. When the centre is high, the rockers must have less curvature than where it is low and near the floor. If the centre of gravity be nearer the ends than to the middle, the chair will immediately be overturned. This principle should be well understood in the construction of every thing which moves bv rocking:. CHAPTER IV. SIMPLE MACHINES, OR MECHANICAL POWERS. ADVANTAGES OF MACHINES. The moving forces which are applied to various useful purposes commonly require some change in velocity, direction, or mode of acting, before they accomplish the desired end. For example, a running stream of water has a motion in one direction only ; by tlie use of machinery,, we change this to an alternating motion, as in the saw of the saw-mill, or to a rotatory or whirling motioin, as in the stones of a grist-inilj. The direct or straightforward power of a yoke of oxen is made, by the employment of the plow, to produce a side-motion to the sod, as well as to turn it through half a circle. The thrashing-machine SIMPLE MACHINES, OR MECHAKICAL POWERS. 43 verts the slowly-acting pace of horses to the swift hum he spiked cylinder. iny instrument used for thus changing or modifying ion is called a machine, whether it be simple or com- c in its structm-e. Thus even a crow-bar, used in lifting les from the earth, by diminishing the motion given by hand and increasing its power, may be strictly tei-med aachinc ; whUe a harrow, which neither alters the rse nor changes the velocity of the force applied, may h more propriety be regarded as simply an implemelit iool. In common language, however, these distinctions not accurately observed, and a machine is usually con- ?red to be any instrument consisting of different mov- parts. ill machines, however complex, may be resolved into I simple parts, or powers. These are, . The Lever; . The Inclined Peane. Tie whed and axle, and the pulley are modified ap- ations of the levee ; and the wedge and the s^rreio of inclined plane, as will be shown on the following es. These six are usually terined the mechanical oers. As they really do not possess any power in ■nselves, but only regulate power, tlie term "simple shines " may be regarded as most correct. THE LAW OF VIRTUAL VELOCITIES. iefore proceeding to the simple machines, it may be I to explain a very important truth, which should be sidered as lying at the foundation of all mechanical osophy , and which renders plain and, simple many things ch would otherwise seem strange or contradictory. 5 is, that the force required to lift any given body is lys m proportion to the weight of that body, taken 44 MECHANICS. together with the height to be raised. For instance, it requires twice the force to raise two pounds as to raise one pound, three times the force to raise three pounds, and so forth. Also, twice as great a force is needed to elevate any weight two feet as one foot, or three times as great for three feet, and so on. Again, combining these together, four times as great a force is required to raise two pounds to a height of two feet as to raise one pound only one foot ; eiglit times as great for four feet, and so on. This holds true, no matter by what kind of ma- chinery it is accomplished. Now this may all seem very simple, but it serves to explain many difficult questions in relation to the real power possessed by all machines. Take another example. Suppose tiiat one wishes to raise a weight of 1000 pounds to a height of one foot. If his strength is equal to only 100 pounds, the weight would be ten times too heavy for liim. He might, there- fore, divide it into ten equal parts of 100 pounds each. Raising each part separately the required height of one foot would be the same as raising one of them ten feet high. The weight is lessened ten times, but the distance is increased ten times. But there are some bodies, as, for example, blocks of stone or sticks of timber, which can not well be divided into parts in actual practice. He there- fore resorts to a machine or mechanical power, through which the same result is accomplished by raising the whole weight in one mass with his single strength ; but in this case as well as the other, the moving force which he •applies must pass through ten times the space of the weight. "We arrive, thei-efore, at the general rule, that the distance moved by the weight is as much less than that moved by the power as the power is less than the weight. This rule is termed by some wiiters the " rule of virtual velocities^'' virtual meaning not apparent or actual, but according to the real effect, because the increase in the velocity of the power makes up for increase in the size THE LEVER. 45 f Weight. This rule will be better understood after con- idering its application to the diflPerent simple machines. The simplest of all machines is the lever. It consists of rod or bar, one end resting upon a prop or fulcrum, F 5g. 41), near which is the weight, W, moved by the and at P. The stone may weigh 1000 pounds ; yet, if it I ten times as near the fulcrum as the man's hand is, a )rce of 100 pounds will lift it ; but it will be moved only tenth part as high as the hand has been moved, as shown Fls -11. Lexer of the second bind. y the dotted lines. By placing the stone still nearer the ilcrum, still less will be the power required to raise it, at then the distance elevated would be also still less. By ifficiently increasing the disproportion between the two arts of the lever, the strength of a child merely might e made to move more than many horses could draw. These performances of the lever often excite astonish- lent at what appears to be out of the coram.on course of lings; yet, when examined by the principles of mechan- s, instead of appearing matters of astonishment, they are lund to be only the natural and necessary results of the ws of force. In the case of the lever just described, it is ^en incorrectly supposed that the power itself sustains le weight. But this is not the case ; nearly the whole ' it rests upon the fulcrum. "We often see proofs of this Tor in common practice, where fulcrums or props entirely sufficient to uphold the enormous weight to be raised ■e attempted to be used. If the weight, for instance, be n times as near the fulcrum as to the power, then nine- nths of the weight rests upon the fulcrum, and the re^ 46 MECHANICS. maining tenth only is sustained by the lifting power. The lever only allows the power to expend itself through a longer distance, nnd thus, by concentrating itself at the weight, to elevate the latter through the shorter distance, according to the rule of virtual velocities already ex- plained. The fulcrum may be placed between the weight and tl:e Fig. 42. power, as in fig. 42, fej i f'^ '^^' ^^^^ power may be ^^ — — ^ -■. — ^^^.^^ . ^-Igg placed between the /% fulcrum and the Leva' of the Jlrst kind. . . « weight, as m ng. 43, the same principle of virtual velocities applying in all cases. Where the fulcrum is between, thfe^ppwer and the weight, as in fig. 42, it is called a lever o/th^^^Mnd, Where the weight is between the fulcrum and the power, as in fig. 41, it constitutes a lever of the second kind. , Where the power is between the fiftcrdm and the weight, as in fig. 43, it is termed a leoer of the third kind. 1. Many examples occur in practice of levers of the first kind. A crow-bar, used to raise stones from the earth, is an instance of this sort ; so is a handspike of any kind used in the A same way. A hammer — for drawing a nail operates as a lever of the first kind, the heel being the ful- crum, the nail the weight, and the hand the power; the distance through which the handle passes being several times greater than that of the cl.iws, the force exerted on the nail is increased in like proportion. A pair of scissors consists of two levers, the rivet being the fulcrum ; and in using them, as every one has observed, a greater cutting force is exerted near the rivets than toward the points. Fig. 43. V Lever of iJie tJiird kitid. THE J.EVEI -EXAMPLES. 47 Piff. 44. "his is owing to the power being expended through a reater distance near the points, according to the rule al- pady explained. Pincers, nippei-s, and other similar in- truments are also double levers of the first kind. A common steelyard is another example, the sliding •eight becoming gradually more effective as it is moved irther from the fulcrum or hook supporting the instru- lent. The brake or handle of a pump is a lever of this lass, the pump-rod and piston being the weight. The common balance is still another, the two arms being saetly equal, so that one weight will always balance the other, and on this its usefulness and accuracy entirely depend. The most sensitive balances have Bight beams with long arms, and ,,the turning-point of hardened steel or agate, in the form of a thin wedge, on which the balance ims almost'witiiout friction. Small balances have been ) sldllfuUy constructed as to turn with one-thousandth art of a grain. 2. Levers of the second kind are less numerous, but not Qcommon. A handspike used for rolling a log is an ex- nple. A wheel-barrow is a leverof the second kind, the ilcmm being the point where the wheel rests on the round, and the weight the centre of gravity of the load, ence, less exertion of strength is required in the arm heu the load is placed near the wheel, except where the round is soft or muddy, when it is found advantageous 1 place the load so that the arm shall sustain a consider- )le portion, to prevent the wheel sinking into the soil. two-wheeled cart is a similar example ; and, for the same ason, when the ground is soft, the load should be placed rward toward the horse or oxen ; on the other hand, on smooth and hard, or on a plank road, the load should be 48 MECHANICS. more nearly balanced. An observance of this rule would often save a great deal of needless waste of strength. A sack-barrow, used in barns and mills for conveying heavy bags of grain from one part of the floor to another, Fig. 45. and in warehouses for boxes, is a lever nearly intermediate ■between the first and second kind, the ■weight usually rest- ing very nearly over the fulcrum or wheels. When the bag of grain is thrown forward of the wheels, it be- comes a lever of the first kind ; when back of the wheels, it is a lever of the second kind. As it is used only on 'hard and smooth floors, and not, like the wheel-barrow, on soft earth, the more nearly the load is placed directly over the wheels, the more easily they will run. 3. In a lever of the third kind, the weight being further from the fulcrum than the power, it is only used where great power is of secondary importance when com- pared with rapidity and dispatch. A hand-hoe is of this class, the left hand acting as the fulcrum, the right hand as the power, and the resistance overcome by the blade of the hoe as the weight. A hand-rake is similar, as well as a fork used for pitching hay. Tongs are double levers of this kind, as also the shenrs used in shearing sheep. The liml:s of .animals, generally, are levers of the third Suck-harfow. ■,cl ESTIMATISTG THE POWEK OF LEVERS. 49 kind. The joint of the bone is the fulcrum; the strong muscle or tendon attached to the bone near the joint is the power; and the weight of the limb, with whatever re- sistance it overcomes, is the Aveight. A great advantage j-esulls from this contrivance, because a slight contraction of the muscle gives a swift motion to the limb, so import- ant in walking and running, and in the use of the arms. ESTIMATHfG THE PC WEE OF LEVEES. The power of any lever is easily calculated by m.easuring the length of its two arms, that is, the two parts into Fig. 48. which it is divided by ,,.-?-"• the weight, fulcrum, '" ' '.y^-'-^:-"""^^""""^" w ^^^ power. In a =--'*'" A\ f lever of the first kind, .--''■'-'' if the weight and Lecer qf the first Und. power be equally dis- tant from the fulcrum, they will move through equal dis- tances, and nothing will be gained ; that is, a power of 100 pounds will lift a weight of 100 pounds only. If the power be twice as far as the weight, its force will be doubled; if three times, it will be tripled; and so forth. In a lever of the second kind, if the weight be equidistant between the fulcrum Fig. 47. and power, the power °r~"----;r-— will move through \ \ "------■;-—_ twice the distance of | | r -- fe^--~— r_ p. the weight, and the "^ #\ n , 1 • . Lever of tlie second kind, power of the mstm- ■' ment will therefore be doubled ; if twice as far, it will be, tripled, and so on, as shown in the annexed figures. The same mode of reasoning will explain precisely to what extent the force is diminished in levers of the third kind. These rules will show in what manner a load borne on a pole is to be placed between two persons carrying it. 3 50 MECHANICS. ir If equidistant between tliem, each will sustain a like por- tion. If the load be twice as near to one as to the other, the shorter end will receive double the weight of the longer. For the same reason, when three horses are j,j„ ^g worked abreast, the two ^ "i horses placed together should have only half the length of arm of the main whiffle-tree as the single horse, fig. 48. The farmer who has a team of two horses un- like in strength, may thus easily know how to adjust the arms of the whiffle-tree so as to correspond with the strength of each. If, for instance, one of the horses possesses a strength as much greater than the other as four is to three, then the weaker horse should be attaclied to the arm of the whiffle- tree made as much longer than the other arm as four is to thi'ee. In all the preceding estimates, the influence of the weight of the lever has not been taken into consideration. In a lever of the first kind, if the thickness of the two arms be so adjusted that it will remain balanced on the fulcrum, its weight will have no other effect than to in- ■— ^;:r ^^ crease the pressure oil the fulcrum ; but if it be of equal size throughout, its longer arm, heing the heavier, will add to its power. The amount thus added will he equal to the excess in the weight of this arm, applied so far along as the centre of gravity of this excess. If, for ex- ample, a piece of scantling twelve feet long, a b, fig. 49, COMBINATION OF LfiVERS. 51 be used as a lever to lift the corner of a building, then the two portions, a c, c d, will mutually balance each other. If these be each a foot in length, the weight of ten feet will be left to bear down the lever. The centre ,of gravity of this portion will be at e, six feet from the fiilcrum, and it will consequently exert a force under the building equal to six times its own weight. If the scant- ling weigh five pounds to the foot, or fifty pounds for the excess, this force will be equal to three hundred pounds. In the lever of the second kind, its weight operates against the moving power. If it be of equal size through- out, this will be equal to just one-half the weight of the lever, the other half being supported by the fulcrum. With the lever of the third kind, the rule applied to the first must be exactly reversed. COMBINATION OF LEVEKS. A great power may be attained without the inconven- ience of resorting to a very long lever, by means of a com- Jig 5Q bination of levers. In fig. i ; ■-■/ 50, the small weight P, act- fe ■; ; /^ \f\Q iiig *s a moving power, ex- * erts a three-fold force on the next lever ; this, in its turn, acts in the same degree on the third, which again increases the power three times. Con- sequently, the moving power, P, acts upon the weight, W, in a twenty-seven-fold degree, the former passing through a space twenty-seven times as great as the latter. A combination of levers like this is employed in self- regulating stoves. It is in this case, .however, used to multiply instead of to diminish motion. The expansion of a metallic rod by heat the hundredth part of an inch acts on a set of iron levers, and the motion is increased, by the time it reaches the draught-valve, to about one hundred times. MECHANICS. A more compact arrangement of compound levers is shown in fig. 51, where the power, P, acts on the lever Fig. 51. A, exerting a force on the lever B five times as great as the power. B acts on the lever C with a force iscreased three times, and this, again, on the weight, W, with a four-fold force. Multiplying 5, 3, and 4 together, the prod- uct is 60 ; hence a force of one pound at P will support 60 pounds at W. By gradu- ating (or marking into li^ ^ notches) the lever C, so that Compound lecert. the distance is measured as the weight is moved along it, a compact and powerful steelyard for weighing is formed. WEIGHING lIACHiNK A valuable combination of levers is made in the con- struction of the weighing machine, used for weighing cat- tle, wagons loaded with hay, and other heavy articles. Fix. 52. n/r>(^-^ p~- ■ B(^"" ^W illM'lllllMimil »jm«i[,i,.j I iii- lllinilllll Weighing Machine. The wagon rests on the platform A (fig. 52,) and this platform rests on two levers at W, W, which presses their other ends both on a central point, and this again bears on THE WEIGHING MACHINE. 53 the lever D, the other end of which is connected by means of an upright rod with the steelyard at F. There are two important points gained in this combina- Fig. 53. tion. In the first place, the levers multiply the power so much that a few pounds' weight will balance a heavy load of hay weighing a ton or more ; and, in the next, the load resting on both the levers, communicates the same force of weight to the central point, from whatever part of the platform it hap- pens to stand on: for if it presses hardest on one lever, PorUMe Platform Scale. it bears lighter, at a cor- responding rate, on the other. In practice, there are Fig. 61 Large Platform Scale. always two pairs, or four levers, which proceed from each 54 MECnANICS. Fig. 56. corner of the platform, and rest on one point at tlie centre. We have taken the two only, to simplify the explanation. A powerful stump-extracting machine, allowing a suc- cession of efforts in the use of the lever, is exhibited by fig. 55. The lever, a, should be a strong stick of timber, furnished with three massive iron hooks, secured by bolts passing through, as represented in the figure. Small or truck wheels are placed at each end of tlie lever, mei'ely for the purpose of moving it easily over the ground. The stump, b, used as a fulcrum, has the chain passing round near its base, while another chnin passes over the top of the stump, c, to be torn out. A horse is at- tached to the lever Lever Stump MacJdne. at d, and, moving to e, draws the other end of the lever backward, and loosens the stump ; Avhile in this position, another chain is made to connect g to h, and the horse is turned about, and draws the lever backward to i, which still further increases the loosening; a few repetitions of this .alternating process tear out the stump. Very strong chains are requisite for this purpose. Large stumps may require an additional horse or a yoke of oxen. Where the stumps are remote Irom each other, iron rods with hooks may be used to connect the chains. The power which may be given to this and to all other A WILD THEORY. 55 modes of using the lever, as we have already seen, depends on the difference between the lengths of its two arms. A yoke of oxen, drawing with a force of 500 pounds on the long arm of a lever 25 feet long, will exert a force on the short arm of six inches equal to 50 times 500 pounds, or 25,000 pounds, on the stump. (See page 292.) It was after an examination of the great power which may be given to the lever by increasing this difference that Archimedes exultingly exclaimed, " Give me but a fulcrum whereon to place my Fig. b6. lever, and I will move the earth !" Admitting the theoretical truth of this exclamation, and supposing there could be a lever which he I might have used for this purpose, \ its practical impossibility may be quickly understood by compnting the whole mass of the glohe ; for such is its enormous size and cu- bical contents, that Archimedes must have moved forward his lever with the strength of a hun- dred pounds and the s-nnftness of a cannon ball for a million years to lift this immense mass the thousandth part of an inch ! WHEEL, AND AXLE. In treating of the lever, it was shown to be capable of exerting a force through a small distance only. Hence, if a heavy body were required to be elevated to any con- siderable height, it would be necessary to accomplish it by a succession of efforts. This inconvenience is removed by a constant and unremitted action of the lever in the form of the wheel and axle. Let the weight, w (fig. 56,) be suspended by a cord 56 MECHANICS. from the end of the lever, a b, and a wheel attached to the lever, so that this cord may wind upon it as the Aveight is elevated ; then let the power be applied at the other end by means of a cord, and a larger wheel be at- y tached, so that this cord too may wind upon the larger wheel. These two wheels (fastened together so as to form one), as they are made to revolve on their axis, will now constitute, in a manner, a succession of levers, acting through an indefinite distance according to the length of the cords. The levers here successively acting are of the " first kind," and the axis of the wheel is the fulcrum. This arrangement constitutes in substance the wheel and axle / and its power, like that of the simple lever, depends on the comparative velocity of the weight and the moving force. If, for example, the larger wheel is four times the circumference of the smaller, a force of one hundred applied to the outer cord will raise a weight of four hundred pounds. The annexed figure exhibits at one view the power ex- erted through the wlieel and axle, where a small weight of 6 pounds will wind up (or balance) other weights separately, weighing 8, 12, or 24 pounds, as the difier- ence increases between the size of the wheel and of the axle, ac- cording to the rule of virtual velocities already explained. The thickness of the rope has not been taken into con- sideration. This is very small when compared with the diameter of the outer wheel, but often considerable when compared with that of the inner. To be strictly accurate Fig. 57. Wheel and axte^ showing the heavier waght for less motUm. WHEKL AND AXLE. — EXAMPLES. 57 ^ therefore, tbe force must be considered as acting at the centre of the rope ; hence the diameter of the rope must be added to the diameter of the wheel. There are various foi-ms of the wheel and axle. In the common windlass, motion is given to the axle by means of a winch, which is a lever like the handle of a grindstone. The windlass used in digging wells has usually four pro- jecting levers or arms. The wheel used in steering a ves- sel is furnished with pins in the circumference, to which the hand is applied in turning it. In the capstan (for weighing anchor) the axis is vertical, and horizontal levers are applied around it, so that several men may work at once. The power of all these forms is easily calculated by the rule of virtual velocities — that is, that the velocity with which the power moves is as many times greater than the velocity of the weight, as the weight exceeds the power. A simple and convenient rule' for computing in numbers the power of wheel-work is the following : Multi- ply all the numbers together which express either the cir- cumferences or diameters of the large wheels, and then Diultiply together all the numbers which express the diam- eters of the smaller wheels or pinions ; divide the greater number by the less, and the quotient will be the power sought. BAND AND COG WHEELS Where great power is required, several wheels and axles may be combined in a man- Fig. b9. ner corresponding with that of the compound system of levers already explained. In this case the axis of one wheel acts on the circumference of the next, producing a continued slower motion; and increasing the power in a corresponding degree. Combined cog-whMs. The wheels are made thus to act by means of cogs or teeth, 3* 58 MECHANICS. Fig. 60. or of bands (fig. 59). In ordinai-y practice, however, com- _ bined wheels are made use of to multiply motion instead of to diminish it, familiar instances of which occur in the grist-mill and thrashing machine. In connecting a system of wheels, the cord or strap may be used where great force is not required, the friction round the circumference being sufficient to prevent slip- ping. Bands arc chiefly useful where motion is to be transmitted to a distance ; as, for example, from a horse- power without a bam to a thrashing-machine within it. Liability of sliding is some- times useful, by preventing the machinery from breaking when a sudden obstruction occurs. Where the force is great, the necessary tension or tightness of the cord produces too great a friction at the axle. In such cases, cogs or teeth must be resorted to. Tiie term teeth is usually applied when they are formed of the same piece as the wheel, as in the case of cast- iron wheels. Cogs are teeth formed separately and inserted into the wheel, as with wooden wheels. Pinions are the small wheels, or, more properly, teeth set on axles. Ji'orm of cogs— a, badly formed ; ft, proper farm. F0E3I OP TEETH OR GOGS. The form of the teeth has a great influence on the amount of friction among wheel- work. Badly formed teeth are represented by the wheel-work at a, in the an- nexed figure, consisting of square projecting pins. When these teeth first come into contact with each other, they FORM OF TEETH OR COGS 59 act ohtiquely together, and thus a part of their force is lost, and they continue scraping together with a large amount of friction so long as they remain in contact. These effects are avoided hy giving to them the curved form, represented by b. Here, instead of pressing each other obliquely, they act at right augles, that is, not obliquely, and instead of scraping, they roll over each other with ease. These curves are as- Fig. ei. certained by mathemat- ,-- ><" ~~>V ~-- ical calculation, which "7^"~~-.^ ,'' V' ^^^y"'' \ can not be here given ; ' /^--^ / A / \ ^ it may be enough to state -"'"^^^ - ^3 — ^B formed that the points '^^^^^^^^^^^^^^k in contact shall always ^^^~ \ ^^^^ work at right angles to I each other. For ordi- Mode of giving tlte best form U> cogs. nary practical purposes, however, they may be made as shown in the annexed figure (fig. 61), by striking circles wh6se diameters shall embrace just three teeth. The points of the teeth thus formed are removed, leaving a blunt extremity, according to the figure. There are a few other mles that should always be ob- served in constructing wheel-work, in order that the wheels mny run easily together, without jerking of rat- tling, the most important of which are the following : 1. The teeth must be of uniform size and distance from each other, through the whole circumference of the wheel. 2. Any tooth must be^in to act at the same instant that the preceding tooth ceases to touch its corresponding tooth on the other wheel. 3. There must be sufficient space between the teeth not only to admit those of the other wheel, but to allow a cer- tain degree of play, which should be equal to at least one- tenth of the thickness of the teeth. 4. The pinions should not be very small, unless the 60 MECnANTCS. Fig. 82. wheels, they act on are quite large. In a pinion that has only eight teeth, each tooth begins to act before it reaches the line of the centres, and it is not diseng.nged as soon as the next one begins to act. A pinion of ten teeth will not operate perfectly if working in a wheel of less than 72 teeth. Pinions of less than six teeth should never be used. 5. To give strength to the teeth of wheels, make the wheels themselves thicker, which increases the breadth of the teeth. 6. Wheel-work is often defective when not made of uniform material, in consequence of the relative number of teeth working together not being such as to equalize the wear of all alike. If the number of teeth on a wheel is di\ided with- out a remainder by the number of the pinion, then the same teeth will repeatedly engage each other, and they will often wear uneven- ly. The number should be so arranged that every tooth of the pinion may work in succession into the teeth of the wheel. This is best effected by first taking a number for the wheel that will be evenly i-ig. 63. divided by the number on the pinion, and ^; then adding one more tooth to the wheel. This will effect a continual change, so that no two shall be engaged with each other twice until all the rest have been gone through with. This odd tooth is called the hiintinff-coff. Cog-wheels are most usually made with the teeth on the outside or cir- cumference of the wheel ; these are termed .ipur-wheels. If the teeth are set on one side of the wheels, they are termed crown-wheels. When they are made so as to work together obliquely, they arc called bevel-wheels, sm in fig. 62. Where the obliquity is Email, the motion may be com- Besd-wlieds. Universal Joint. THE PITLLET. 01 muiiicated by means of the universal joint, as shown in fig. 63. This is commonly used in the thrashing-machine, where there is a slight change in the direction of motion between the horse-power and the thrasher. THE PFLLET. Fig. 65. PaUey doubling the fixed at one end pass round a movable grooved wheel, and be grasped by the hand at the other end : then, in liftingr any weight attached to the wheel, by drawing up the cord, the hand will move with twice the velocity of the weight. It will, therefore, exert double the degree of force. This operates precisely as a succession of levers of tlie second kind, the fixed cord being the fulcrum, and the cord drawn up by the hand, the power. It thus constitutes one of the simplest kinds of the pulley, fig. 64. The wheel is called a sheave ; the term pulley is applied to the block and sheave ; and a combination of sheaves, blocks, and ropes is called a taxikle. There are various combinations of single , pulleys for increasing power, the most com- mon of which, and least liable to become deranged by the cord being tlirown ofi" the wheels, is shown in fig. 65. In this and in all similarly constructed pulleys, the weight is as many times greater than the power as the number of cords which support the lower block. If there be six coi-ds, as in the figure, the weight will be six times the power. FuUey of six-fdUl power. 62 MECHANICS. Where a cord is passed over a singlu fixed w heel, as in fig. 66, or over two or more wheels, no power is gained, the moving force being the same in velocity as the weight. Such pulleys are sometimes, however, of use by altering the direction of the force. The latter is applied with advantage to unloading or pitching hay by means of a horse-power, saving much time and labor, as explained on a future page. Among the many applications of the pulley, one is shown in the ac- companying figure (fig. 67) rep- resenting Packer's Stone Lifter, for raising large boulders from the soil, PuUey with liTincreme of weighing from one to four and five P°^^- tons, and afterwards placing them in walls. It is also employed for tearing out small or partly decayed stumps. The usefulness of the pulley depends mainly upon its lightness and port- able form, and the facility with which it may be made to operate in al- most any situation. Hence it is much used in building, and is extensively applied in the rig- ging of ships, in Paclcer's Stam Lifter. the computation of its power there is a large drawback, not taken into account in the preceding calculation, which materially lessens its advantage; this is the friction of the wheels and blocks and the stifihess of the cordage, THE IXCXIXED PLANE. 63 ■which are often so great that two-thirds of the power is lost. THE INCLUfED PLANE. The inclined plans or slope possesses a power which is estimated by the proportion which its length bears to the height. If, for example, the plane be twice as long as the perpendicular height, then in rolling the body a up the inclined plane (fig. 68), it will move through twice the distance required to lift it directly from b to c. Therefore only one-half the strength else i-equired need be exerted for this purpose. The same reasoning will apply to any other proportion between the height and length ; that is, the more gradual or less steep the slope becomes, the greater will be the advantage gained. A familiar example occurs in lifting a loaded barrel into a wagon : the longer the plank used in rolling it, the less is the exertion needed. A body, in rolling freely down an inclined plane, acquires the same velocity that it would attain if dropped perpen- dicularly from a height equal to the perpendicular height of the plane. Thus, if an inclined plane on a plank road be 100 yards long and 16 feet high, a freely running wagon, left to descend of its own accord, will move 32 feet per second by the time it reaches the bottom,, that being the velocity of a stone falling 16 feet. Or, a rail- car on an inclined plane 145 feet high will attain a speed of 96 feet per second, or more than 65 miles an hour, at_ the foot of the plane, which is equal to the velocity of a Btone falling three secqnds, or 145 feet. ASCENT IN BOADS. All roads not perfectly level may be regarded as inclined planes. By the application of the preceding rule, we 64 MECHANICS. may discover precisely how much strength is lost in draw- ing heavy wagons up hill. If the load and wagon weigh a ton, and the road rise one foot in height to every five feet of distance, then the increased strength required to draw the load will be one-fifth of its weight, or equal to 400 pounds. If it rise only one foot in twenty, then the increase in power needed to ascend this plane will be only 100 pounds. The great importance of preserving, as nearly as practicable, a perfect level is obvious. There are many roads made in this country, rising over and descending hills, which might be made nearly level by deviating a little to the right or to the left. Suppose, for example, that a road be required to connect the two points Bmiles a and b (fig. 69), three miles apart, but separated by a lofty hill midway between them, and one mile in diameter. Passing half a mile on either side would entirely avoid the hill, and the road thus curved would be only one hundred and forty-eight yards, or one-twelfth of a mile longer. The same steep hill is ascended perhaps fifty to five hundred times a year by a hundred different farmers, expending an amount of strength, in the aggregate, sufficient to elevate ten thousand tons annually to this height, as a calculation will at once show — more than enough for all the increased expense of making the road level.- It is interesting and important to examine how much further it is expedient to carry a road tlirough a circuitous level course than over a hill. To ascertain this point, we must take into view the resistance occasioned by the rough surface or soft material of the road. Roads vary greatly THE EESISTANCE OF BOADS. 65 in this particular, but the following may be considered aa about a fair average. In drawing a ton weight (including wagon) on freely running wheels, on a perfect level, the strength exerted will be found about equal to the follow- ing : On a hard, smooth plank road 40 pounds. On a good Maciidam road 60 " On a common good hard road 100 '• On a soft road about 200 " Now let us compare this resistance to the resistance of drawing up hill. First, for the plank i-oad — forty pounds is one-fiftieth of a ton ; therefore a rise of one foot in fifty of length will increase the draught equal to the resistance of the road. Hence the I'oad might be increased fifty feet in length to avoid an ascent of one foot ; or, at the same rate, it might be increased a mile in length to avoid an ascent of one hundred and five feet. But in this estimate the increase in cost of making the longer road is not taken into account. K making and keeping in repair be equal to three hundred dollars yearly per mile, and one hundred teams pass over it daily, at a cost for traveling of four cents each per mile, being four dollars daily, or twelve hundred dollars per annum, then the cost of making and repair would be one quarter of the expense of traveling over it. Therefore the mile should be diminished one quarter in length to make these two sources of expense counterbalance each other. Hence a road with this amount of travel should, with a reference to public accommodation, be made three-fourths of a mile longer to avoid a hUl of one hundred and five feet. This estimate applies to loaded teams only. For light car- riages the advantages of the level road would not be so great. One-half to five-eighths of a mUe would, there- fore, be a fair estimate for all kinds of traveling taken together 60 MECHANICS. The following table shows the rise in a mile of road for different ascents : Tor a rise of 1 foot in 10, the road ascends 528 feet per mile, do, 1 do. 13, do. 406 do. do do. 15, do. 852 do. do. do. 20, do. 264 do. do. do. 25, do. 211 do. do. do. 30, do. 176 do. do. do. 35, do. 151 do. do. do. 40, do. 133 do. do. do. 45, do. 117 do. do. do. 50, do. 106 do. do. do. 100, do. 53 do. do. do. 125, do. 43 do. The same kind of reasoning applied to a common good road will show that it will be profitable for the public to travel about half that distance to avoid a hill of one hundred and five feet. In this case the whole yearly cost of the road, including interest on the land, and the cost of repairs, would not usually be more than a tenth part of the same cost for plank, or would not exceed thirty dollars. On rail-roads, where the resistance is only about one- fifth part of the resistance of plank roads, the dispropor- tion between the draught on a level and up an ascent be- comes many times greater. Thus, if a single engine move three hundied and fifty tons on a level, then two engines will be required for an ascent of only twenty feet pei mile, four engines for fifty feet per mile, and six engines for eighty feet per mile. Such estimates as these merit the attention of the farmer in laying out his own private farm roads. It may ^ be worthy of considerable effort to avoid a hill of ten or twenty feet, which must be passed over a hundred times yearly with loads of manure, grain, hny, and wood. The greatly increased resistance of soft materials, also, is too rarely taken into account. A few loads of gravel, well applied, would often prevent ten times the labor in plow- FOEM AND MATERIALS FOR ROADS. 67 ing through deep ruts, to say nothing of the breaking of harness and wagons by the excessive exertions of tlie team. FORM AND MATERIALS FOE EOADS. The depth of the mud in common roads is often un- necessarily great, in consequence of heaping together with the plow and scraper the soft top-soil for the raised Fig. 70. Section of badly fanned road. carriage-way. When heavy rains fall, this forms a deep bed of mud, into which the wheels work their way, and cause extreme labor to the team. A much better way is to scrape off and cart away into the fields adjoining all the sofV, rich, upper surface, and then to form the harder subsoil into a slightly rounded carriage-way, with a ditch on each side. Such roads as this have a very hard and firm foundation, and they have been found not to cut up Fig, 71. Section, of weU formed road. into ruts, nor to form much mud, even iu the wettest sea- sons. On this hard foundation six inches of gravel will endure longer and form a better surface than twelve inches on a raised " turnpike" of soft; soil and mud. It frequently happens that the form of the surface in- creases the quantity of mud in a road, by not allowing the water to flow oflT freely. The earth is heaped up in a high ridge, but having little slope on the top (fig. 70), ' where the water lodges, and ruts are formed, the only dry portions being on the brink of the ditches, where the water can escape. Instead of this form, there should be a gradual inclination from the centre to the ditches, as shown in fig. 71. This inclination should not exceed 1 68 MECHANICS. foot in 20. On hill-sides the slope should all be toward the higher ground, as in fig. 72. Hard and durable roads are made on the plan of Telford. Their foundation is rounded stones, placed upright, with the smaller or sharper ends upward. The smaller stones Fig. 72. Section of road for Ml-sUles. are placed near the sides, and the larger at the centre, thus giving to tlie road a convex form. The spaces are then filled in with small broken stone, and the whole covered witli the same material or with gravel. The pressure of wagons crowds it compactly between the stones, and forms a very hard mass. IMPOETANCE OF GOOD EOADS. The principles of road-making should be better under- stood by the community at large. Farmers are deeply interested in good roads. Nearness to market, and facili- ties for all other kinds of communication, are worth a great deal, often materially afiecting the price of land and its products. The difierence between traveling ten miles through deep mud, at two miles per hour, with half ,a load, and traveling ten miles over a fine road, at five miles per hour, with a full load, should not be forgotten. " In the absence of such facilities," says Gillespie, " the richest productions of nature -Haste on the spot of their growth. The luxuriant crops of our western prairies are sometimes left to decay on the ground, because there are no rapid and easy means of conveying them to market. The rich mines in the northern part of the State of New GOOD AND BAD BOADS. 69 York are comparatively valueless, because the roads among the mountains are so few and so bad, that the expense of the transportation of the metal would exceed its value. So, too, in Spain it has been known, after a succession of abundant harvests, that the wheat has actually been allowed to rot, because it would not repay the cost of carriage." Again, " When the Spanish government re- ' quired a supply of grain to be transferred from Old Castile to Madrid, 30,000 horses and mules were necessary for the transportation of four hundred and eighty tons of wheat. Upon a broken-stone road of the best sort, one-hundredth of that number could easily have done the work." He further adds, in speaking of the improvements in roads made by Marshal Wade, in the Scottish Highlands, " His military road is said to have done more for the civilization of the Highlands than the preceding efforts of all the British monarclis. But the later roads, under the more scientific direction of Telford, produced a change in the state of the people which is probably unparalleled in the history of any country for the same space of time. Large crops of wheat now cover former wastes ; fanners' houses and herds of cattle are now seen where was previously a desert; estates have increased seven-fold in value and annaal returns ; and the country has been advanced at least one hundi'ed years." THE WEDGE. The wedge is a double inclined plane, the power being ^pplied at the back to urge it forward. It becomes more and more powerful as it is made more acute ; but, on ac- count of the enormous amount of friction, its exact power can not be very accurately estimated. It is nearly always urged by successive blows of a heavy body, the momentum of which imparts to it great force. All cutting and piercing instruments, as knives, scissors, 70 MECHANICS. cliisels, pins, needles,' and awls, are wedges. Tlie degree of acuteness must be varied according to circumstances ; knives, for instance, which act merely by pressure, may be made with a much sharper angle than axes, which strike a severe blow. For cutting very hard substan(!es, as iron, the edge must be formed with a still more obtuse angle. The utility of the wedge depends on the friction of its surfaces. In driving an iron wedge into a frozen or icy stick of wood, as every chopper has observed, the want of sufficient friction causes it immediately to recoil, unless it be previously heated in the fire. The efficacy of nails depends entirely on the friction against their wedge-like faces. THE SCREW The screw may be regarded as nothing more than an Fig. 74 inclined plane winding round the surface of a cylinder (fig. 74). This may be easily under- stood by cutting a piece of paper in such a form that its edge, a b (fig. 75), may represent the inclined plane ; then, beginning at the wider end, and wrapping it about the cylindrical piece of wood, c, the upper edge of the paper will represent the thread of the screw. Although' the friction attending the use of the screw is considerable, and without it it would not retain its place, yet the slope of its in- p.^, ,.5 clined thread being so gradual, it possesses great power. This power is multiplied to a still greater degree by the lever which is usually employed to drive it, a (fig. 76). If, for example, a screw be ten inches in circumference, and its thread half an inch apart, it exerts a force twenty THE SCREW. 71 times as great as the moving power. If it be moved by a lever twenty times as Jong as the diameter of the screw, here is another increase of twenty times in force. Multiplying 20 by 20 gi\es 400, tlie whole amount gained by this combination, and by which a man applying one hundred pounds in force could exert a pressure equal to twenty tons. About one-third or one-fourth of this should, however, be deducted for friction. When the screw is combined With the wheel and axle (fig. 77), it is capable of exerting great power, which may be readily calculated by multiplying the power of the screw and its lever into the power of the wheel and axle. (Scewj and Itver combined. THE KNEE-JOINT POWER. Fig. 77. Fig. 78. The knee-joint or toggle-joint is usually regarded as a com- pound lever, and consists of two rods connected by a turn- ing joint, as represented in fig. 78. The outer end of one of the levers is fixed to a solid beam, and the other connected with a movable block. When the joint a is forced in the direc- tion indicated by the arrow, it produces a powerful pressure upon the movable block, which in- creases as the lever approaches a straight line. This is easily understood by the rule of virtual velocities, for the force moves with a velocity many times greater than the Knee-joint power. 73 MECHANICS. power given to tlie block, and this relative difference in- creases as the joint is made straighten This power is made use of in the lever printing-press, where the greatest force is given just as the pressure is completed. Another example occurs in the Lever Wash- ing-machine (fig. 79), which is worked by the alternating motion of the handle, A, pressing a swinging board, per- Lever Wasking-machine. forated with holes, with great force against the clothes next to one side of the water-box. Like the printing- press, this machine exerts the greatest power just as the motion of the lever is completed, and at the time it is most needed. The same principle is exhibited in KendaWs Cheese-press (fig. 80), where the lever and the wheel and axle are combined with the two knee-joints, one on each side of the press, drawing down a cross-beam upon the cheese with a greatly multiplied power. Diclc's Cheese-press (fig. 83), operates on a similar principle. Figs. 81-2 show the structure of its working LTSVEU WASUIXG-MACmXE. Fig. SO. 73 KendalVs Cheese-press. part, the clotted lines indicating the position of the lerer, which is inserted into a roller or axle, and, by turning, drives the movable iron blocks asunder, and raises tlie cheese against the broad screw-head abo\e, as shown in fig. 82. In fig. 81, the raised lever shows that the blocks Fig. 82. rig. 81. ^i"6 ^t ^vs\j near together, but are crowded asunder as the lever is press- ed downward. This cheese-press is made of cast-iron, and has great power; to try it, weights were in- creased upon the lever, until the iron i frame broke with a force equal to six- teen tons. The power exerted by a rolling- mill, where bars of iron are flattened in their passage between two strong, rollers, is precisely like that of the knee-joint. The only 4 74 Dick^s cast-iron Cheese-press. Fig. 04. difference is, that the rollers, which may be considered as a constant succession of levers coming into play as they re- volve, are both fixed, and consequently the bar has to yield between them (fig. 84). The greatest power is 'exerted just as the bar receives the last pressure from the rollers. The most powerful and lapidly- •working straw-cutters are those which draw the straw or hay between two rollers, one of which is furnished with knives set around it parallel with its axis, and cutting on the other, which is covered with un- tanned ox-hide (fig. 85). (See page 39'i.) Principle of the knee-joint in the ralUng-miii STRAW CUTTEES. Mg. 85. 75 nide Roller Straw OuUer, CHAPTER V. APPLICATION OF MECHANICAL PRINCIPLES IN THE STRUCTURE OF SIMPLE IMPLEMENTS AND PARTS OF MACHINES. In contriving the more difficult and complex macliines, the principles of jnechanics must be closely studied, to give every part just that degree of strength required, and to render their operation as perfect as possible. But in making the more common and simple implements of the farmer, mere guess-work too often becomes the only guide. Yet it is highly useful to apply scientific knowledge even in the shaping of a hoe handle or a plow-beam. The simplest tool, if constantly used, should be formed with a view to the best application of strength. The laborer who makes with a common hoe two thousand 76 MECHANICS. strokes an hour, should not wield a needless ounce. If any part is heavier than necessary, even to the amount of half an ounce only, he must repeatedly and continually lift this half ounce, so that the whole strength tlius spent would be equal, in a day, to twelve hundred and fifty pounds, which ought to be exerted in stirring the soil and destroying weeds. Or, take another instance :' A farm wagon usually weighs nearly half a ton ; many might be Fig. 86. W V. lladl'j-famed fn.-k handle. reduced fifty pounds in \yeight by proportioning every part exactly to the strength required. How much, then, should we gain here? Every farmer who drives a wagon with its needless fifty pounds, on an average of only five miles a day, draws an unnecessary weight every year equal to the conveyance of a heavy wagon-load to a dis- tance of forty miles. Now a knowledge of mechanical science will often ena- ble the farmer, when he selects nnd buys his implements, to judge correctly whether every part is properly adapted to the requii-ed strength. We shall suppose, for instance, that he intends to purchase a common pitchfork. He finds them difierently formed, although all are made of the Fig. 87. g. Badly-formed fork handle. best materials. The handles of some are of equal size throughout. Some are smaller near the fork, as in fig. 86, and others arc larger at the same place, as in fig. 87. Now, if he understands the principle of the lever, he knows that both of these are wrongly made, for the right hand placed at a is the fulcrum, where the greatest strength is needed, and therefore the one represented by fig. 88 is both stronger and lighter than the others. PRINCIPLES IN THE STRUCTURE OP IMPLEMENTS. 77 Again, hoe handles, not needing much strength, chiefly require liglitness and convenience for grasping. Hence, in selecting from two such as are represented in the annex- ed figures, the one should be chosen which is lightest near Fig. 88. Well-formed fork handle. the blade, nearly all the motion being in that direction, because the upper end is the centre of motion. The right hand, at a, acting partly as the fulcrum, the hoe liandle should be slightly enlarged at that place. Fig. 89 rep- resents a well-formed handle ; fig. 90,' a clumsy one. Rake handles should be made largest at the middle, or where the right hand jjresses. Rake-heads should be much larger at the centre, and tapering to the ends, where the stress is least, the two parts operating as two distinct lev- Fig. 89. a a WeU-formtd hoc handle. ers, acting from the middle. Wood horse-rakes might be made considerably lighter than they usually are by ob- serving the same principles. The greatest strength requir- ed %r plow-beoims is at the junction with the mould-board, and the least near the forward end, or furthest from the fulcrum or centre of motion. . Now it may be that the farmer who has had much ex- perience may be able to judge of all these things without Fig. 90. \T Sadly-formed hoe handle. a knowledge of the science. But this scientific knowledge would serve to strengthen his experience, and enable him to judge more accurately and understandingly by showing him the reasons ; and in many cases, where new imple- ments were introduced, he might be enabled to form a 78 SIECHAjaOS. good judgment before he had incurred all the expense and losses of unsuccessful trials. Even so simple a form as that of an ox-yoke is often made unnecessarily heavy. Fig. 91 represents one that is faulty in this respect, by having been cut from a piece of Fig. 91. a. ' timber as wide as the dotted lines a o/ and being thus weakened, it requires to be correspondingly large. Fig. 92 is equally strong, much lighter, and is easily made from a stick of timber only as wide as a 5 in the former figure. In the heavier machines, it is necessary to know the de- gree of taper in the diiferent parts with accuracy. A thorough knowledge of science is needed to calculate this Fig. 92. with precision, but a superficial idea may be given by cuts. If a bar of wood, formed as in a (fig. 93), be fixed in a wall of masonry, it will possess as much strength to sup- port a weight hung on the end as if it were the same size throughout, as b. The first is equally strong with the second, and much lighter.* The same form doubled must * The simple style of this worlc precludes an oxplanntifin of the mode of calculation for determinini^ tlie exact form. Wliere the sticli tapers only on one side, it is a common parabola; if on all sides, a cubic parabola. VAEIOUS EXAMPI.ES. 79 be given if the bar is supported at the middle, with a weight at each end, or with the weight at the middle, supported at each end, as c. This form, therefore, is a proper one for many parts of implements, as the bars of whifHe-trees, the rounds of ladders, string pieces of bridges, and any cross-beams for supporting weights. The proper form for rake-teeth and fence-posts, the pressure being nearly alike on all parts, is nearly that of a long wedge, or with a straight and uniform taper. Therefore a fence- post of equal size throughout contains nearly twice as mucli timber as is needed for strength only. The form of these parts must, however, be modified to suit cii'cumstauces ; as whiflle-trees must be large enough Fis. 93. v^fSX5^^^^ V ^^.V^^^Sf^^^^:^^ at the ends to receive the iron hooks, wagon-tongues for ironing at the end, and spade handles for the easy grasp of the hand. The axle-trees of wagons must be made not only strong in the middle, or at centre of pressure, but also at the en- trance of the hub ; because the wheels, when thrown side- wise in a rut, or on a sideling road, operate as levers at that point, a and b (fig. 9-1), show the manner in which the axles of carts may be rendered lighter without lessen- ing the strength, a being the common form, and b the im- proved one. 80 MECUAincs. Sometimes several forces act at once on different parts. For example, the spokes of wagon-wbeels require strength at the hub for stiffening the wheel ; they must be strong in the middle to prevent bending, and large enough at Fig. 94. the outer ends, where they are soonest weakened by de- cay. Hence there should be neai-ly a uniform t-aper, slightly larger at the middle, and with an enlargement at the outer end, as e (fig. 94). A very useful rule in practice, in giving strength to Structures, is this : The strength of every square beam or stick to support a weight increases exactly as the width increases, and also exactly as the square of the depth iu- creases. For example, a stick of timber eight inches wide and four inches deep (that is, four inches thick), is exactly twice as strong as another only four inches wide, and witli the same depth. It is twice as wide, and consequently twice as strong ; that is, its strength increases just as the width increases, according to the rule given. But where one stick of timber is twice as deep, the width being the same, it is four times stronger ; if three times as deep, it is nine times stronger, and so on. Its strength increases as the square of the depth, as already stated. The same rule will show that a board an inch thick and twelve inch- es wide will be twelve times as strong when edgewise as when lying flat. Hence the increase in strength given to whiffie-trees, fence-posts, joists, rafters, and string-pieces to farm-bridges, by making them narrow and deep. CALCtTLATlNG THE STRENGTH OF PARTS. 81 Again, the strength of a round stick increases as the cuhe of the diameter increases ; that is, a round piece of wood three inches in diameter is eight timers as strong as one an inch and a lialf in diameter, and twenty-seven times as strong as one an inch in diameter. This rule shows that a fork handle an inch and a half in diameter at the middle is as much stronger than one an inch and a quarter in diameter, as seven is greater than four. Now this rule would enable the farmer to ascertain this without break- ing half a dozen fork handles in trying the experiment, and it avouIJ enable the manufacturer to know, without Fig. 95. the labor of trying many experiments, that if he makes a fork handle an inch and a half at the middle, tapering a quarter of an inch toward the ends, it will enable the workman to lift with it nearly twice as mnch hay as with one an inch and a quarter only through its whole length. A mode of adding strength to light bars of wood, by means of braces, is shown in fig. 95, representing light whiffie-trees, stiffened by iron rods in a simple manner. The same method is sometimes adopted to advantage in - making light fruit ladders, and for other purposes. CHAPtEE VI. FRICTION. The subject of friction has been postponed, or merely alluded to, to prevent the confusion of considering too many things at once. As it has an important influence on the action of machines, it is worthy of careful investigation. 4* 82 MECHANICS. It is familiar to most persons, that when two surfaces slide over each other while pressing together, the minute unevenness or roughness of their surfaces causes some ob- struction, and more or less force is required. This resist- ance is known as friction. EOLLIN-G FEICTION. The term is also applied to the resistance of one body rolling over another. This may be observed in various degrees by rolling an ivory ball successively over a carpet, a smooth floor, and a sheet of ice ; the same force which would impel it only a few feet on the carpet would cause it to move as many yards on a bare floor, and a still greater distance on the ice. The' two extremes may be seen by the force required to draw a carriage on a deep sandy or loose-gravel road, and on a rail-road. NATUBE OF rEICTION. If two Stiff bristle brushes be pressed with their feces together, they become mutually interlocked, so that it will be quite difficult to give them a sliding motion. This may be considered as an extreme case of friction, and serves to show its nature. In two pieces of coarse, rough sandstone, or of roughly-sawed wood, asperities interlock in the same way, but less in degree ; a diminished force is consequently required in moving the two surfaces against each other. On smoothly planed wood the friction is still less ; and on polished glass, where the unevenness can not be detected without the aid of a powerful magnifying glass, it is reduced still further in degree. ESTIMATIIirG THE AMOUNT OF FKICTION. In order to determine the exact amount of friction be- tween different substances, the following simple and in* TO ASCERTAIN THE AMOUHT OF PEICTIOX. 83 genious contrivance is adopted : An inclined plane, a h (fig. 96), is so formed that it may be raised to any desired height by means of the arc of a circle and a screw. Lay a flat surface of the substance we wish to examine upon this inclined plane, and another smaller piece or block of the same substance upon this surface ; then raise the plane until it becomes just steep enough for the block to slide down by its weight. Now, by measuring the degree of slope, we know at once the amount of friction. Suppose, for example, the two surfaces be smoothly-planed wood : it will be found that the plane must be elevated about half as high as its length ; therefore we know, by the Fig. 90. properties of the inclined plane, heretofore explained, that it requires a force equal to one-half the weight of the wooden block to slide it over a smooth wooden smface. Some kinds of wood have more friction than others, but this is about the average.* From the result of this experiment we may learn tha,t to slide any object of wood across a floor requires an amount of strength equal to one-half the weight of the object. A heavy box, for instance, weighing two hundred pounds, can not be moved without a force equal to one hundred pounds. It also shows the impropriety of placing * These experiments may be made with tolerable accuracy, by hook- ing a spring-balance into any object of known weight, and then observ- ing the comparative force as measured by the balance, to draw it over a perfectly level surface. 84 MECHAKICS. a heavy load upon a sled in winter for crossing a bare wooden bridge or a dry barn floor, the friction between cast-iron sleigh-shoes and rough sanded plank being nearly equal to one-third of the whole weight.* Hence a load of one ton (including the sled) would require a draught equal to more tban six hundred pounds, which is too much for an ordinary single team. On bare unfrozen ground the friction would be still greater. On a plank bridge, with runners wholly of wood, it would be equal to half the load. All these facts may be readily proved by actually placing the sled on slopes of plank and of earth, and by observing the degree of steepness required for sliding down by its own weight. In a similar way, we are enabled easily to ascertain the force required to draw a wagon upon any kind of level surface. Suppose, for example, that we wish to determine the precise amount of force for a wagon weighing, with its load, one ton, on a plauk road. Select some slight de- scent, where the wngon will barely run with its own weight. Ascertain by a level just what the degree of de- scent is ; then divide the weight of the wagon by the de- gree of the slope, and we shall have tlie force sought for. To make this rule plainer by an example : It will be found that a good, newly-laid plank track, if it possess a de- scent of only one foot in fifty feet distance, will be suflS- cient to give motion to an easy-running wagon ; therefore we know that the strength required to draw it on a level will be only one-fiftieth part of a ton, or forty pounds. The resistance offered to the motion of a wagon by a Macadam road, by a common dry road, and by one with six inches of mud, may be readily determined in the same way by selecting proper slopes for the experiment. If by such trials as these the farmer ascertains the fact that a * On cleiin hard wooJ, with polislied metallic shoes, the friction would be much lc&8, or .1 fourth or fifth. EBSULTS WITH THE DTN"AMOMETEE. 85 few inches of mnd are sufficient to retard his wagon so much that it will not run of its own weight down a slope of one foot in four (and few common roads are ever steeper), then he may know that a force equal to one-fourth the whole weight of his wagon and load will he required to draw it on a level over a similar road — that is, tho enormous force of five hundred pounds will be needed for one ton, of which many wagons will constitute nearly one- half Hence he can not fail to see the great importance, for the sake of economy, and humanity to his team, of providing roads, whether public or private, of the hardest and best materials. EESTJLTS WITH THE DTNAMOMETEK. Another mode of determining the resistance of roads is by means of the Dynamometer.* It resembles a spring- balance, and one end is fastened to the wagon and the other end connected with the horses. The force applied is measured on a graduated scale, in the same way that the weight Of any substance is measured with the spring- balance. A more particular description of this instrument will be given hereafter. Careful experiments have been made with the dynamom- eter to ascertain accurately the resistance of various kinds of roads. The following are some of the results : On a new gravel road, a horse will draw eight times as much as the force applied ; that is, if he exerts a force equal to one hundred and twenty-five pounds, he will draw half a ton on such a road, including the weight of the wagon, the road being perfectly level. On a common road of sand and gravel, sixteen times aa much, or one ton. On the best hard-earth road, twenty-five times as much, or one and a half tons. • From two Greek words, dunamit, power, and mAreo, to meawre. 86 MBCHAiaCS. On a common broken-stone road, twenty-five to tlurty- eix times as much, or one and a half to two and a quarter tons. On the best broken-stone road, fifty to sixty-seven times as much, or three to four tons. On a common plank-road, clean, fifty times as much, or thi-ee tons. On a common plank-road, covered thinly with sand or earth, thirty to thirty -five times as much, or about two tons. On the smoothest oak plank-road, seventy to one hund- I'ed times as much, or four and a half to six tons. On a highly-finished stone track- way, one hundred and seventy times as much, or ten and a half tons. On the best rail-road, two hundred and eighty times as much, or seventeen and a half tons. The firmness of surface given to a broken-stone road by a paved foundation was found to lessen the resistance about one-third. On a broken-stone road it was found that a horse could di'aw only about two-thirds as much when it ^^•as moist or dusty as when it was dry and smooth; and when muddy, not one-half as much. When the mud was thick, only about one quarter as much. The character of the vehicle has an influence on the draught. Thus, a cart, a part of the load of which is sup- ported by the horse, usually requires only about two-thirds the force of horizontal di-aught needed for wagons and carriages. On rough roads the resistance is slightly diminished by springs. On soft roads, as earth, sand, or gravel, the number of pounds draught is but little afiected by the speed; that is, the resistance is no greater in driving on a trot than on a walk ; but on hard roads it becomes greater as the velocity increases. Thus a carriage on a dry pavement requires one-half greater force when the horses are on a trot than WIDTH O? WHEELS, 87 on a walk ; but on a muddy road tlie difference between the two rates of speed is only about one-sixth. On a rail- road, where a draught of ten pounds will draw a ton ten miles an hour, the resistance increases so much at a high degree of speed as to require a force of fifty pounds per ton at sixty miles an hour — that is, it would require five times as much actual power to draw a train one hundred miles at the latter rate as at the former; but as the speed is six times as great, the actual force during a given time would be five times six, or thirty times as great. WIDTH OF WHEELS. Wheels with wide tire run more easily than naiTow tire, on soft roads ; on hard, smooth i-oads, there is no sensible difference. Wide tire is most advantageous on gravel and new broken-stone roads, both by causing the vehicles to ran more easily, and by improving the surface. For the latter reason, the New York turnpike law allows six-inch wheels to pass at half price, and twelve-inch wheels to pass free of tolL Wheels with broad tii-e on a farm would pass over clods, and not sink between them ; or would only press the surface of new meadows, without cutting the turf. But where the ground becomes muddy, the mud closes on both sides of the rim, and loads the wheels. On clayey soils, narrow tire unfits the roads for broad wheels. For these reasons, broad wheels are decidedly objection- able for clayey or soft soils, and tliey are chiefly to be recommended for broken-stone roads, and gravelly, or dry, sandy localities. They are also much better foi- the wheels* of sowing or diilling machines, which only pass over mellowed surfaces. The lai'ger the wheels are made, the more easily they run ; thus a wheel six feet in diameter meets with only half the resistance of a wheel three feet in diameter. A flat piece of wood, sliding on one of its broad suF" 88 MECHANICS. faces, is subject to the same amount of friction as wlien sliding upon its edge. Hence the friction is the same, provided the pressure be the same, whether the surface be small or large.* Or, in other words, if the surfaces are the same, a double pressure produces a double amount of friction ; a triple pressure, a triple amount, and so on. A narrow sleigh-shoe usually runs with least force, for two reasons : first, its forward part cuts with less resist- ance through the snow ; and, secondly, less force is re- quired to pack the narrow track of snow beneath it. The only instance in which a wide sleigh-shoe would be best, is where a crust exists that would bear it up, and through which a narrow one would cut and sink down. VELOCITT. Friction is entirely independent of velocity ; that is, if a force of ten pounds is required to turn a carriage wheel, this force will be ten pounds, whether the carriage is driven one or five miles per hour. Of course, it will re- quire five times as much force to draw five miles per hour, because five times the distance is gone over ; but, measured by a dynamometer or spring-balance, the pressure would be the same. In pi-ecisely the same way, the weight of a stone remains the same, whether lifted slowly or quickly. If the friction of the wheels of a wagon on their axles be equal to ten pounds, driving the horse fast or slowly will not increase or diminish it. But fast driving will require more strength, for the same reason tliat a man would need more strength to carry a bag of wheat up two flights of stairs than one, in one minute of time. FEICTION AT THE AXLE. A carriage wheel, or any other wheel revolving on an •Generally speakingj this is very nearly correct; but when the prcB Bure is intense, the friction is slightly less on the smaller surface. SIZE OF AVHEKLS ON BOADS. 89 axle, will run more easily as the axle is made smaller. This is not owing to the rubbing surfaces being less in size, as some mistakenly suppose, for it has just been shown that this makes veiy little or no difference, pro- 'vided the pressure is the same; but it is owing to the leverage of the wheel on the friction at the axis ; and the smaller the axlo, the greater is this leverage ; for, if the axle, a (fig. 97), be six Hg. 97. inches in circumference, and the wheel, b c, be ten feet in circumference, then the outer part of the wheel will move twenty times fuither than the part next the axle. Therefore, accord- ing to the i-ule of virtual velocities (already ex- plained,) one ounce of force at the rim of the wheel will overcome twenty ounces of friction at the axle ; or if the axle were twice as large, then, according to the same rule, it would require two ounces to over- come the same friction acting between larger surfaces. For this reason, Lirge wheels in wheel-work for multi- plying motion, if not made too heavy, rnn with less force than smaller ones, the power acting upon a larger lever. Horse-powers for thrashing-machines, consisting chiefly of a large, light crown-wheel, well stiffened by brace-work, have been found to run with remarkable ease; a good example of which exists in what is known as Talpin^s horse-power, when made in the best manner. . FKICTIOSr-WHEELS. On the preceding principle, friction-wheels or friction- rollers are constructed, for lessening as much as possible 90 MECHANICS. Friction-wheels. the friction of axles in certain cases. By this contrivance, the axle, a (fig. 98), instead of revolving in a simple hole or cavity, rests on or between the edges of two other wheels. As the axle re- volves, the edges turn with it, and the rubbing of surfaces is only at the axles of these two wheels. If, therefore, these axles be twenty times smaller than the wheels, the friction will be only one-twentieth the amount without them. This contrivance has Fig. 99. been strongly i-ecom- mended and con- siderably used for the cranks of grind- stones (fig. 99), but it w.ns not found to answer the intended purpose so well as was expected, for the very plain reason that, in using a grindstone, nearly all the friction is at the circumference, or between the stone and the tool, which friction-wheels could not, of course, remove. i!iiiiiiliiiiiii!ii;iiiiiiiiil)Tr' Grindstone on Friction-wheels. LUBEICATIN-G SUB3TAN0ES. Lubricating substances, as oil, lard, and tallow, applied to rubbing surfaces, greatly lessen the amount of friction, partly by filling the minute cavities, and partly by sepa- rating the surfaces. In ordinary cases, or where the machineiy is simple, those substances are best for this purpose which keep their places best. Finely-powdered black-lead, mixed with lard, is for this reason better for greasing carriage wheels than some other applications. Drying oils, as linseed, soon become stiff by drying-, and LrBEICATING SUBSTANCES. 91 ■ are of little service. Olive oil, on the contrary, and some animal oils, whicli scarcely dry at all, are generally pre- ferred. To obtain the full benefit of oil, the application must be frequent. According to the experiments made with great care by Morin,at Paris, the friction of wooden surfaces on wooden surfaces is from one quarter to one-half the force applied ; and the friction of metals on metals, one-fifth to one- seventh — varying in both cases with the kinds used. Wood on wood was diminished by lard to about one-fifth to one-seventh of what it was before ; and the friction of metal on metal was diminished to about half what it was before ; that is, the friction became about the same in both cast's after the lard was applied. To lessen the friction of wooden surfaces, lard is better than tallow by about one-eighth or one-seventh; and tal low is better than dry soap about as two is to one. For ii'on on wood, tallow is better than dry soap about as five is to two. For cast-iron on cast-iron, polished, the friction with the different lubricating substances is as follows : Wiiter 31 Soap 20 Tallow 10 Larii 7 Olive oil '. 6 Lard and bbick-lead 5 When bronze rubs on wrought iron, the friction with lard and black-lead is rather more than with tallow, and about one-fifth more than with olive oil. With steel onr bronze, the friction with tallow and with olive oil is about one-seventh less than with lard and black-lead. As a general rule, there is least friction with lard when hard wood rubs on hard wood ; with oil, when metal rubs on wood, or metal on metal — being about the same in er j^j 301 1 i ZBD (I ,iii 1 ili.illi sso! i II \ S4I 1. « Mi 'l' 1 1 :!0 lILiliL IL • ' iJ ' 200 lli![| '1 l,H IHO IllitI ll!l \m 1(11 ISO ij'iii. "■ 140 m ] m ' 80 60 W L 20 The markings of the Self-recording Dynamometer. vibrations on a slip of paper while the plow is in opera- tion. A pencil is fixed to the index, and presses, by means of a spring, against the paper, thus giving a true register 102 MECHAJIICS. Fig. 112. of the force exerted. To prevent tlic pencil from con- stantly marking on the same line, the paper is made to move slowly in a side direction, so that all the vibrations are shown, as represented in fig. Ill, and they may be ac- curately examined and read off at leisure, a and h repre- senting the forces of two different plows, drawn through a single furrow across the field. The motion of the paper is effected by being placed on two rollers, one of which unwinds it from the other. This roller is made to turn by means of a wheel running on the ground, which gives mo- tion to the roller through an endless chain, working a cog- Avheel by means of an endless screw. The cylindrical dyn- Self-recording Dynamometer. amometer, shown in fig. 112, is used for this purpose, lengthwise upon which the two rollers are placed for holding the paper. With this in- strument a permanent register might be made of the force required for different plows, with an accuracy not liable to dispute. WATEKMAN S DTNAMOSIBTEE. All difficulties h.ive been completely overcome by the recent invention of H. Waterman, of Hudson, N. Y. His dynamometer was used with entire success at the Auburn reaper trial in 1866, and at the trial of plows at TJtica, in 1867, under tlie Committee of the N. Y. State Agricul- tural Society. A full description of all the parts would require too much space for the character of this work; the following is a brief explanation of the mode of its opera- tion: This dynamometer is furnished with a spiral spring, like those we have already described, Avorking a piston in a cylinder of water. To this, two dial plates are added waterman's dynamometer. 103 one of whicli shows, by a slowly revolving index, the ex- act distance which the hors'js have traveled, without looking at in for a distance of more than five miles. The otlier dial plate gives a perfectly accurate record of the whole force expended from the commencement of the experiment to its termination. In otlier Avords, it takes all the different and varying forces, and adds them accu- I'ately in one aggregate or whole, seen at a glance on the dial plate under the ey& We shall attempt a brief description of the modes by which the indexes on these two dial plates are moved. The mode by which the distance traveled is recorded will be easily understood. A wheel one yard in circum- ■ ference runs on the ground and communicates its motion by a cord, to a wheel attached to the dyna- mometer. Thi^^, by means of an endless screw and cog-work, moves the index slowly around the face, and thus records the distance traveled. There are two parts of this portion of the apparatus, which deserve a description. One is tlie wheel around which the cord passes in connection Mitli the wheel which runs on the ground. It is very important that the exact number of the revolutions of this wheel should be maintained, as compared with those of the ground wheel. This is regulated as follows : The groove in this wheel is made by screwing together two beveled edged wheels, as shown in the annexed section, fig. 113. By placing thin pa- per between these two wheels, the width of the groove may be varied with the utmost - accuracy, and the cord consequently let further in towards the centre. The other part which we desire to notice, although not original in this dynamometer, is the manner in which the index is car- ried around the face of the dial plate. There are two cog-wheels on the Fame axis, one with a hundred cogs, and the other with ninety-nine — both fitting into the same pinion. Consequently, when one has made the entire revr 104 MECHANICS. olution, the other lias fallen one cog behind, and a hnnd- red revolutions are required for the index, placed upon one of them, to come around again so as to coincide with its first position. The endless screw attached to the band- wheel already no- ticed moves one cog nt every yard advanced, and the in- dex passing around in a hundred revolutions, it is obvious that it will show 10,000 yards, or more than five miles. We shall now attempt to describe that part of the ma- chine which furnishes an accurate record of the force. In doing this, we omit most of the details and vary some of the parts, in order to make the explanation simpler and clearer, the object being merely to explain the principle. The band- wheel a, fig. 114, (shown also in fig. 113,) re- volves once for every yard of onward movement, as already stated. In doing so, it causes the aim d c, to vi- brate backwards and forwards, on a pin at d/ the connecting rod b c being set near the circumference of the wheel b, this vibrating movement is shown by the dotted lines at /" and i. The slide A moves on this vibra- ting rod, by being connected with the spiral spring already described, which indicates the force of the draught ; the stronger the draught, the further this slide is moved toward c. When there is no draught at all, the rod e remains at the pivot d, and has no motion ; but as the slide h is moved successively along the arm, this rod e is thrust backwards and forwards, more or less, accord- ing to the force of the draught. This thrusting move- ment turns the ratchet wheel ff faster or slower as this force varies. ^ A self-recording index is connected with WATEEMAW'S DYNAMOMETER. 105 this wheel by an arrangement similar to that already de- scribed for registering the distance. This explanation shows the principle of the self-regis- tering attachment, but in one respect it must be varied in order to be entirely accurate. The ratchet wheel must necessarily permit some play of the click or pawl, which would soon lead to serious error. This is wholly prevent- ed by facing the wheel with India rubber, and causing the pawls to press this Tndia rubber surface. It will be observed that a movement of this wheel is made at every revolution of the band-wheel, or once in every yai-d ; and in traveling a hundred yards, a hundred such movements are made. Every one of tliese may be different in amount from the others, yet the whole sum will be accurately measured. It is absolutely essential that every part be finished with perfect workmanship, so that there may be no play or rattling of the teeth, producing loss of motion. Its measurements have been entirely satisfactory, although its records must necessarily vary with the condition of the cutting ;edge of plows, with the running order of mow- ing machines, the temper or sharpness of the knives, and the skill of the manager or driver. A more general use of the dynamometer would doubt- less result in important advantage to farmers as well as plow-makers. The trials which have been made, both in this country and in Europe, have proved that a great dif ^ference exists in plows, as to ease of draught, — some plows requiring a force more than fifty per cent greater than others, to turn a furrow of equal width and depth-. Hence the farmer who employs the plow which mns most freely may accomplish as much by the use of two horses, as another can do by using one of hard draught by em- ploying three horses. 106 MECHANICS. DYNAMOMETER FOE EOTAET MOTION. All these dynamometers apply only to simple, onwarc^ draught, as in plowing, drawing wagons, harrowing, etc. There is another, represented in fig. 115, of very ingenious but complux construction, which shows the force require(^ in working any rotary machine, such as thrashers, straw-i cutters, and mills, and showing, at the same time, the ve? locity, and recording the number of revolutions made. The whole machine is supported by a cast-iron frame- Fig. 115. Dynamometer /or measvrijig the farce and velocity of thratUng-machinet, work, on four small ^vhcels with flanges, like the wheels of rail-cars, that it may be conveniently run up on a temporary rail-way to the thrashing or other machine to be tried. The band-wheel /, on the shaft e, is connected with the machine imdcr trial, and the force is supposed, in this in- Bta ce, to be applied by hand to the handle a, on the fly- wheel. DYNAMOMETER FOE EOTAET MOTION. 107 When the fly-wheel is turned in the direction shown by the arrow, it causes the two cog-wheels to revolve, and moves the band in the direction shown by the other arrow. Now, whatever force is required to turn the wheel f, con- nected with the machine under trial, must be overcome by a corresponding force applied to t!ie handle a, because the wheel-work is so adjusted that this handle moves with the same velocity as the band on the band-wheels. The wheel /, being connected by the band to the wheel d, which is on the same axis or shaft as the cog-wheel /, the resistance of the macliine under trial tends to keep the cog-wheel I from turning, until enough force is ap- plied to the handle a, to set the cog-wheel k in motion. Now the greater the resistance, the greater will be the power needed at the handle. This power, tlierefore, is measured accurately in the following manner : The axle g, of the cog-wheel I, rests at its further end in an oblong liole or mortise, which allows it liberty to play, or rattle up and down within narrow limits. This same axle, g, passes through a hole in the lever i so that when it rattles up and down, it carries tliis lever up and down with it. The other part of the lever turns on the shaft h of the other cog-wheel. Now when the man at the fly-wheel applies his force to tlie handle a, the resistance of the machine under trial causes the cog-wheel I to refuse to turn ; consequently, his force, instead of turning it, lifts it up in the mortise, and raises the lever with it. As he increases his force against the handle, let weights be hung on the lever, until, at the very moment that the wheel begins to revolve, the weights shall be just heavy enough to keep the lever down in the mortise. This weight, therefore, will measure the exact force needed to turn the machine : the greater the resistance of the machine, the greater must be the weight, There is another weight, J, used to balance the lever and cog-wheel I, while the machine is at rest, or before 108 MECHANICS. the force is applied to it, so that the weight at m shall rep- resent the force truly. The weight m is, of course, to be multiplied by the power it exerts on the lever i, which should be graduated like the bar of a. steelyard. There are a few other parts of this dynamometer not yet described. One is the cylinder o, nlled with oil, in which a perforated piston works, preventing the rapid vibration of the lever «", as the force varies, precisely similar to the cylinder of oil described in fig, 110, p. 100. Another part is the pendulum /?, with the whfel r, which measures the time. The use of this instniment has been already attended with jjome important results in detecting the great amount of friction existing in some thrashing-machines of high reputation, which has been found to amount, in certain cases, to more than one-half of tlie whole power applied. It is only by detecting so great a waste that we avp ena- bled to take measures for its prevention. CHAPTER VIII. APPLICATION OF LABOE. Most of the moving powers applied by the farmer to accomplish labor are the exertions of animal strength. A principal object of the preceding pages is to point out how this strength can be applied in the most economical manner, and to aid in the substitution of cheap horse- power for more costly human labor. It will doubtless sontribute to the end to exhibit the relative efficiency of each, as well as the results of strength differently applied. The amount of work which any machine is capable of performing is denoted by comparing this amoint with POWER OP HORSES. 100 the power of a single horse ; hence the common expres- sions of twenty, or fifty, or a hundred horse-power engines. The strength of different horses varies greatly, hut the expression, as commonly understood, indicates a force equivalent to raising or pressing with a force equal to 150 pounds 20 miles a day, at the rate of two and a half miles an hour. This is the same as 33,000 pounds raised one foot in one minute. The results of numerous expeilments in different places give the actual power of the average of horses at somewhat less than this ; and there is no douht that, for most of the farm-horses of this country, the result would be considerably less. The power of a strong English draught-horse has been ascer- tained to be about 143 pounds for 22 miles a day, at 2f- miles an hour. Many American horses are scarcely more than half as strong. The strength of a man, working at the best advantage, is estimated at one-fifth that of a horse. As the speed of a horse increases, his strength of draught diminishes very rapidly, till at last he can move only his own weight. This is owing to three reasons : first, the load moves over a greater space in a given time, and if, for instance, the speed be doubled, half the load only can be carded with the same quantity of powei', according to the law of virtual velocities ; secondly, the horse has to carry the full weight of his body, whatever his speed may be, and the force expended for this purpose alone must, , therefore, be doubled as the speed is doubled ; thirdly, a very quick and unaccustomed motion of the muscles is in itself more fatiguing than the ordinary or natural velocity The following table shows the amount of labor a horse of average strength is capable of performing in a day at different degrees of speed, on canals, rail-roads, and on turnpikes. The force of draught is estimated at about 83 pounds. This is considerably less than the horse-power used in estimating the force of machinery, but it is as much 110 MECHANICS. as an oi'dinary horse can exert without being improperly fatigued with continued service : Vdoelty Duration of the Work aecompliekedfor one da. y, in tons, drawn per hour. day's work. Hours. one mile. Miles. On a canal. On a vail-road. On a turnpike. 2M, 11' la 520 115 14 3 8 243 ft 13 3M, 5»|,. 153 83 10 4 4'U 103 73 9 5 a».|io 53 67 7.3 6 2 30 48 6 7 I'la 19 41 6.1 8 I'U 13.8 36 4.5 9 'Ik 9 33 4 10 M« 6.6 28.8 3.6 From the preceding table it will be seen that a liorse, at a moderate walk, will do more than four times as much work on a canal as on a raU-road ; but the resistance of the water increases as the square of the velocity, and therefore when the speed reaches five miles an hour, the rail-road has the advantage of the canaL On the rail- road and turnpike the resistance is about the same, whether the speed be great or little, the chief loss with fast driving resulting from the increased difiiculty with which the horse carries forward his oun body, which weighs from 800 to 1200 pounds. The table also shows that when it becomes necessary to drive rapidly with a load, it should be continued but for a very short space of time ; for a horse becomes as much fatigued in an hour, •when drawing hard at ten miles an hour, as in twelve hours at two and a half miles an hour ; because when a boat is driven through the water, to double its velocity not only requires that twice the amount of water should be moved or displaced in a given time, but it must be moved with twice the velocity, thus requiring a four-fold force. The muscular formation bf a horse is such that he will exert a considerably greater force when working horizon- POWER OF MEN. Ill tally tlian up a steep, inclined plane. On a level, a horse is as strong as fire men, but up a steep hill he is less strong than three ; for three men, carrying each 100 pounds, will ascend faster than a horse with 300 pounds. Hence the obvious waste of power in placing horses on steeply inclined tread-wheels or aprons. The better mode is to allow them to exert their force more neai'ly horizontally, by being attached to a fixed portion of the machine. For the same reason, the common opinion is' erroneous that a horse can draw with less fatigue on an undulating than on a level road, by the alternations of ascent and descent calling different muscles into play, and relieving each in turn ; for the same muscles are alike exerted on a level and on an ascent, only in the latter case the fatigue is much greater than the counterbalancing relief. Any per- son may convince himself of the truth oft this subject by first using a loaded wheel-barrow or hand-cart for one day on a level, and for the next up and down a hill ; bearing in mind, at the same time, that the human body is better fitted for climbing and descending than that of a horse. A draught-horse can draw 1600 pounds 23 miles in a day, on a good common road, the weight of the carriage included. On the best plank-road he will draw more than twice as niuch. A man of ordinary strength exerts a force of 30 pounds for 10 hours a day, with a velocity of 2^ feet per second. He travels, without a load, on level ground, during 8|- hours a day, at the rate of 3.7 miles an hour, 31:|- miles a day. He can carry 111 pounds H miles a day. He can Carry in a wheel-bnrrow 150 pounds 10 miles a day. * Well-constructed machines for saving human labor by means of horse-labor, when encumbered with little fric- tion, will be found to do about flue times as much work for each horse as where the same work is performed by an equal number of men. For example : an active man will saw twice each stick of a cord of wood in a day. 112 MECHANICS. . Six horses, with a circular saw, driven by means of a good horse-power, will saw five times six, or thirty coi-ds, work- ing the same length of time. In this case the loss by friction is about equal to the additional force required for attendance on the machine. Again : a man will cut with a cradle two acres of wheat in a day. A two-horse reaper should therefore cut, at th^ same rate, ten times two, or twenty acres. This has not yet been accomplished. We may hence infer that the machinery for reaping has been less perfected than for sawing wood. It should, however, be remenibei-ed, that great force is exertod, and for many hours in a day, in cutting wheat witli a cradle, and tlierefore less than twenty acres a day may be regarded as the medium attainment of good i-eaping-machines when they sliall become perfected. Applying tlie same mode of estimate, a horse-cultivator will do the work of five men with hoes, and a two-horse plow the work of ten men with spades. A horse-rake accomplishes more than five men, because human force is not strongly exerted with the hand-rake. In using diflTerent tools, the degree of force or pressure applied to them varies greatly with the mode in which the muscles are exerted. The following table gives the results of experiments with human strength, variously applied, for a short period : Force of the hands Forte of the tool on the tool. on the object. With a drawing-knife 100 lbs. 100 lbs, " a liir^e ;ms;i!r, botli hands 100 " about 800 " " a screw-driver, one hand 84 " 250 " " a bencli-vice li;indle 72 " about 1000 •• " a windlass, with one hand 60 " 180 to 700 " " a hand-saw 36 " 36 " " a brace-bit, revolvin;; 16 " 150 to 700 " Twisting with tliunib and fingers, but- ton-screw, or small soiew-drlver..... 14 " 14 to 70 " The force given in the last column will, of course, vai-y BEST WAT TO APPLY STRENGTH. 113 with the degree of leverage applied ; for example, the arms of an auger, when of a given length, act with a greater increase of power with a "small size than with a large one. This degree of power may be calculated for an auger of any size, hy considering the arms as a lever, tlie centre screw the fulcrum, and the cutting-blade as the weight to be moved. The same mode of estimate will apply to the vice-handle, the windlass, and the brace-bit. Every one is aware that a heavy weight, as a pail of water, is easily lifted when the arm is extended downward, but with extreme difficulty when thrown out horizontally. In the latter case, the pail acts with a powerful leverage on the elbow and shoulder-joint. For this reason, all kinds of hand labor, with the arms pulling toward or pushing directly from the shoulders, are most easily per- formed, while a motion sidewise or at right angles to the arm is fa;; less effective. Hence great strength is applied in rowing a boat or in using a drawing-knife, and but little strength in turning a brace-bit or working a dasher-chum. Hence, too, the reason that, in turning a grindstone, the puUing and thrusting part of the motion is more powerful than that through the other parts of the revolution. This also explains why two men, working at right angles to each other on a windlass, can raise seventy pounds more easily than one man can raise thirty pounds alone. This principle should be well understood iu the construction, or selection of all kinds of machines for hand labor. CHAPTER IX. MODELS OF MACniNES. Serions errors might often be avoided, and sometimnft gross impositions prevented, by understanding the differ ence between the working of a mere model, on a miniature 114 MECHANICS. scale, and the working of the full-sized machine. It is a common and mistaken opinion that a well-constructed model presents a perfect representation of the strength and mode of operation of the machine itself. When we enlarge the size of any thing, the strength of each part is increased according to the square of thei diameter of that part ; that is, if the diameter is twice as great, then the stiength will be four times as great ; if the diameter is increased three times, then the strength will be nine times, and so on. But the weight increases at a BtiU greater rate than the strength, or according to the cube of the diameter. Thus, if the diameter be doubled (the shape being similar), the weight will be eight times greater ; if it be tripled, the weight will be twenty-seven times greater. Hence, the larger any part or machine is made, the less able it becomes to support the still greater increasing weischt. If a model is made one-tenth the real size intended, then its different parts, when enlarged to full size, become one hundred times stronger, but they are a thousand times heavier, and so ai-e all the weights or parts it has to sustain. All its parts would move ten times faster, which, added to their thousand-fold weight, would increase their inertia and momentum ten thousand times. For this reason, a model will often work perfectly when made on a small scale ; but when enlarged, the parts become so much heavier, and their momentum so vastly greater, from the longer sweep of motion, as to fail entii'ely of success, or to become soon racked to pieces. This same principle is illustrated in every part of the works of creation. The large species of spiders spin- thicker webs, in comparison with their own diameter, than those spun by the smaller ones. Enlarge a gnat until its whole weight be equal to that of the eagle, and, great as that enlargement would be, its wing will scarcely have attained the thickness of writing-paper, and, instead of supporting the weight of the animal, would bend down WORKS 07 CBEA.TIOK FBEB FROM MISTAKES. 115 fi-om its own weight. The larger spiders rarely hare legs 60 slender in form as the smaller ones ; the form of the Shetland pony is quite different from that of the large cart-horse ; and the cart-horse has a slenderer form than the elephant. The common flea will leap two hundred times the length of its own body, and the remark has been sometimes made that a man eq)ially agile, with his present size, would vault over the highest city-steeple, or across a river as wide as the Hudson at Albany. Now, if the flea were increased in size to that of a man, it would become a hundred thousand times stronger, but thirty million times heavier; that is, its weight would become three hundred times greater than its corresponding strength. Hence we may infer that the enlarged flea would be no more agUe than a man; or that, if a man were proportionately reduced to the size of a flea, he could leap to as great a distance. All this serves to illustrate in a striking manner the great difference in the working of models and of machines* CHAPTER X. CONSTEUCriOH AJSD USB OF fXrM IMPLEMENTS AlTD MA- CHINES — IMPLEMENTS FOR TILLAGE. The application of mechanical principles in the struc- ture of the simpler parts of implements and machines has been already treated of. It remains to examine more particularly those machines chiefly important to the farmerj and to show the application of these principles in bheii use and operation. 116 MECHANICS. Farm implements and machines for working the soil should be, as far as possible, simple and not complex, be> cause they mostly meet with an irregular resistance, con- sisting of hard and soft soil and stones variously mixed together. A locomotixe is made up of many parts ; but having a smooth surface to traverse, the machinery works uniformly and uninjured ; but if in its progress it met with formidable obstructions and uneven resistance, it would be soon racked and beaten to pieces. Hence the long-continued and uniform success of the simple plow ; as well as the failure of complex digging machines, unless worked exclusively in soils free from stone. A complex machine, that meets with an occasional severe obstruction, receives a blow like that of a sledge ; and when this is repeated frequently, the probability is that some pait will be bent, twisted, knocked out of place, or broken. If the machine be light, the chances are in its favor ; but if heavy, its momentum is such that it can scarcely escape severe injury. If composed of many distinct parts, the derangement or breakage of one of these is sufficient to retard or put a stop to its working, and men and teams must stand idle till the mischief is repaired. Hence, after the trial of the multitude of implements and machines, we fall back on those of the most simple form, other things being equal. The crow-'bar has been employed from time immemorial, and it will not be likely to go out of use in our day. For simplicity nothing ex- ceeds it. Spades, hoes, forks, etc., are of a similar char* icter. The plow, although made up of parts, becomes a single thing when all are bolted and screwed together. For this reason, with its moderate weight, it moves through the soil with little difficulty — turning aside from obstructions, on account of its wedge form, when it can- not remove them. The harrow, although composed of many pieces, becomes a fixed solid frame, moving on through the soil as a single piece. So with the simple* IMPOETANCE OF SIMPLICITY IN MACHINES. 117 cultivators. Contrast these with the ditching machine (Pratt's) considerably used some years ago, but ending in entire failure. It was ingeniously constructed and well-made, and when new and every part uninjured, woiked admirably in some soils. But it was made up of many parts, and weighed nearly half a ton. These two facts fixed its doom. A complex machine, weighing ' half a ton, moving three to five feet per second, could not strike a large stone without a formidable jar; and con- tinued repetitions of such blows bent and deranged the working parts. After using a while, these bent portions retarded its working ; it must be frequently stopped, the horses become badly fatigued, and all the machines were finally thrown aside. This is a single example of what must always occur with the use of heavy complex machinery working in the soil. Mowing and reaping machines may seem to be exceptions. But mowers and reapers do not work in the soil or among stones ; but operate on a soft, uniform, slightly resisting substance, made of the small stems of plants. Every farmer knows what becomes of them when they are repeatedly driven against obstruc- tions by careless teamsters. There is another formidable objection to complex ma- chines — ^this is, their cost. Even with some of proved value, the expense is a serious item with moderate farm- ers. Mowers and reapers, 8130; grain drills, $80 or $90; thrashing machines, $100 to $400 ; horse rakes, $45 ; hay tedders, $80 to $100 ; iron rollers, $50 to $100 ; and even some of the eificient new potato diggers are offei-ed for not less than $100. Placing all tliese sums, and many others for necessary tools together, the whole wiU be found a large outlay — more economical by far, it is true, than doing without them; but greater simplicity and consequent cheapness, as well as durability, would facilitate progress in agricultural improvement. A single machine, Comstock's spader, is offered at $250 — twenty 118 MECIIAKICB, times the price of the best cast-iron plow, and ten times that of the most finished steel plow. And yet it is ap- plicable only to land free from stone. The object of these remarks is to caution farmers against investing money in Fig. lie. newly invented con- trivances of liisrh \\ ^.i^ss^^ promise at first, which are liable to the objection point- ed out ; and also in- Kooioo Pimv. ventors an'd manufacturers themselves against engaging in enterprises having at hand golden promises, but with failure in the distance. PLOWS. The simplest plow, used probably in the earlier ages of the world, and found at the present day only among de- graded nations, is the crooked limb of a tree, with a pro- jecting point for tearing the surface of the earth. The above figure represents an improvement on the first rude implement, and is found at the present day in Northern Pig. 117. India. Fig. 116 shows the Kooloo plow, consisting wholly of wood, except the iron point. Fig. 117 exhibits the implement now used in Moi-occo, which resembles the India plows, with the addition of a rude piece of tim- ber as a mould-board. Both these perform very imperfect PLOWS. 119 work, and have remained with little change for centuries, the owners not enjoying the benefit of agricultural read- Fig. 118. ing and intelligence. Fig. 118 is a step in advance, and represents a plow still used in some parts of Europe. In the less improved portions of Germany, the Baden plow. Fig. 119- Fig. 120. Badm Plow. represented by Fig. 119, is employed, and does not difier greatly from the " hull plow " commonly used in this country at the beginning of the present century. Great im- provement has been made within the past fifty years, among others hy the ingenuity and labors of Jethro Wood, and move recently by a great number of inventors and manufacturers in different parts of the country. Wood introduced the cast-iron plow into general and successful use, ^"^^ imprcmed rum. by cheapening its construction and perfecting its form, 120 MECIIAXICS. and others Iiave made important improvements, including the steel mould-board now largely employed at the West. Cast-iron plows have been generally used throughout the Eastern States ; but for the peculiar soil of the West, it has been found absolutely necessary to use steel plows exclusively ; and for the purpose of keeping them at all Fig. 121. Moline Flow, times sharp for cutting the vegetable fibre and separating the parts of the soil readily, the practice is common to carry a large file or rasp for this purpose. These steel plows are made of plate previously rolled. They are be- coming partially introduced also at the East, although in hard and gravelly soils the cast-iron mould-board is pre- ferred by many, and Fig. isa. I'egarded as even more durable. The steel plate plow is lighter than the cast- iron, but is more expensive. The ac- companying figure A steel mow. (Fig. 121,) represents the celebrated "Moline plow," made: by Deere & Co., of Moline, III., one of the best and most extensively introduced among the Western steel imple- ments ; and Fig. 132 shows the more common form of the steel plow as made by several manufacturers at the CHARACTER OF A GOOD PLOW. 121 East. Good steel plows cost about double those made of cast-iron. (See page 282.) CHAEACTEK OF A GOOD PLOW. Every good plow should possess two important quali- ties. The first relates to its working. It should be easily drawn through the soil, and run with unifonn depth and steadiness. The second refers to the character of the work when completed. The inversion of the sod, especially if encumbered with vegetable growth, should be complete and perfect ; and the mass of eai-th thus inverted should be left as thoroughly pulverized as practicable, instead of being laid over in a solid, unmoved mass. This is of the greatest importance on heavy soils, and is highly useful on those of a lighter character, except, it may be, clear sand or the lightest gravels. The harrow, at best, is an imper- fect loosener; it pulverizes the surface, but its weight, and that of the team, press down the mass below. Whatever loosening, therefore, can be accomplished in plowing is a gain of vital importance. • THE CUTTING EDGE. The point and cutting edge of the plow perform the first work in separating the furrow-slice from the land. It is important that this edge should not only do the work well, but with the greatest possible ease to the team. The force required to perform this cutting is greater than many sup- pose. The gardener who thrusts his sharp spade into the hard earth uses more force than afterwards in lifting and inverting the spit. "We may hence infer that a large part of the power of the team is expended in severing the fur- row-slice. This inference has been proved correct by the use of the dynamometer, in connection with carefully con- ducted experiments, which have shown the force usually 6 122 MECHaSTICS. expended for cutting off the side and bottom of the furrow- slice, in firm soils, to exceed all the rest of the force re- quired to draw the plow. The point or share should therefore be kept sharp, and form as acute an angle as practicable, as shown in Fig. 123. Some plows which other- Fig. 133. Fig. 124. Fig. 125. S * y^ — // Fig. 127. wise work well are hard to draw because the edge, being made too thick or obtuse, raises the earth abruptly. Fig. 124. Where stones or other obstructions exist in the soil, it is important that the line of the cutting edge form an acute angle with tha land-side, or, in other words, that it form a sharp wedge, (Fig. 125.) It will then crowd these obstruc- tions aside, and pass them with greater e.ise than when formed more obtuse, as shown in Fig. 126, for the same reason that a sharp boat moves more freely through the water than one which is blunt or obtuse. The gardener or ditcher proves this advantage when he thrusts a sharp- pointed shovel. Fig. 127, more easily through stony or gravelly soil, than one with a square edge. (Fig. 128.) But when the soil is free from stones, or obstructions, or is filled with small roots whiph the plow should cut off, as in the Western prairies, the sharpness of the edge is more injportant than its form ; and hence ^he reaspn that the use pf {;he r3.sp or file bcpomes neces- Fig. 128. THE CDTTING EDGE. 123 saiy ill the field, to keep a sharp cutting edge at all times on tlie share. Note.— It has been shown in the Report of the Trial of Plows at Utica, that so far as yet determined by experiment in England, about thirty-five per cent of the whole required drauglit is expended in ovei-coming the ^friction of the implement on its bottom and sides, about fifty-five for cutting the furrow-slice, and only about ten per cent for turning the sod. Hence the exclusive attention formerly given to forming the monld-board, as a means of reducing the draught, should have been directed more to lessening the force required for cutting the hard soil. These experiments, however, do not appe:ir to have been entirely satisfactory, especially for the light plows of this country ; and it may be interesting to test their accuracy by calculation. The average weight of hard earth is about 125 lbs. per cubic foot ; and the average draught of plows at the trial near Albany in 1850 was about 400 lbs. for a furrow- slice a foot wide and six inches deep. If a team in turning such sod moves two miles an hour, it raises a slice three feet long, equal to a cubic foot and a half (weighing 187 lbs.,) six inches eticli second — which would be the same as raising 31 lbs. thiee feet per second, which is the velocity of the plow. The mere force required to tuin the sod, not esti- mating friction, would therefore be only one-thii-teenth of the 400 lbs. of draught force. But the friction of di-y earth on smooth iron is never less than one-half its weight; and if the earth is slightly plastic, its friction often is equal to, and sometimes exceeds, its weight. Taking the smallest amount, the friction on the mould-bo;ird would be equal to half the weight of the portion of sod resting on the mould-board, or about 31 lbs. This increased weijrht would also add equally to the fric- tion of the sole of the plow, or 31 lbs. more — making the whole friction ■62 lbs. ; which added to the weight of the sod would amount to 93 lbs. — or more than one-fifth of the whole draught. To ascertain the amount of friction, suppose the plow weighs 100 lbs. Half its weight would be 50 Ibs^, the friction on the sole of the plow. The friction of the sides would vary greatly with plows, being very small with those having a perfect centre-draught, or with no tendency to press against the hind on the left. The whole friction and force for lifting the sod would therefore be about 150 lbs. ; leaving 250 lbs. as the force for cutting the slice. A very easy running plow would leave a much smaller force — some as low as 200 lbs. This estimate is liable to great vari;ition. A wet and cl.ayey soil would double the friction ; a very hard piece of ground would add much to the force required for cutting the slice ; if loose, the force would be com- paratively small ; or if quite moist, this force would be also much dim- ished ; while the great difference in the draught of plows would vary the results still farther. The estimate, however, for soil dry enough to be friable, and of medium tenacity, is probably not far from correct, for plowing in this country — showing that most of the force required is foi. 124 MECHANICS. the act of cutting, and indicating the importance of giving special at- tention to the cutting edge. THE MOtTLD-BOAED. A prominent diflPerence between good and bad plows results from the form of the mould-board. To un- derstand the best form, it must be observed that the slice is first cut by the forward edge of tlie plow, and then one side is gradually raised until it is turned completely over, or bottom side up. To do this, the mould-board must combine the two properties of the wedge and the screw. The position of the furrow-sUce, from the time it is first cut until completely inverted, may be represented by placing a leather strap flat upon a table, and then, while Fig. 12.9. holding one end, turning over the other, so as to bring that also flat upon the table, as in Fig. 129. Now, if the sole object were merely to invert the sod, the mould-board might have just such a shape as to fit the fiirrow-slice while in the act Fig. 130. of turning over, or resemble pre- cisely the twist of this leatiier strap. All the parts of this screw will be found to fit a straight-edge, if measured across at right angles, as indicated by the dot- ted lines in Fig. 130. But there are two objections to this form in practice. The first is that the sod is laid over smoothly and un- broken, and without being at all pulverized. On heavy and hard soils this is a serious fault. The other objection is that the sod is elevated as rapidly at the first movement, when its weight is considerable, as just before falling, when its pressure on the mould-board is slight. These difli- culties are in part removed by giving the mould-board a THK MOULD-BOAKD. 125 shorter twist towards its rear. This form is distinctly- shown in thfe figure of Holbrook's Stubble Plow, on a future page ; and it contributes largely to that crumbling movement of the sod, so important for effecting pulveriza- , tion. The mould-board of a plow is capable of an almost infi- nite variety of forms, and the multitude of inventors have each adopted a different one. Some have made their selections by repeated random trials ; while others, among whom Thomas Jefferson was the first, devised a series of straight lines, mathematically arranged, by which uniform- ity was given to the shape; The limits of this work pre- clude a full explanation. Many modifications in com- bining lines have been adopted, the most successful of which is that of Ex-Governor Holbrook, of Vermont, whose plows made according to these rules have perform- ed admirably. It is less essential that farmers generally should understand these mathematical principles, provided they find a plow that will do good work ; because, as al- ready shown, the form of the mould-board has compara- tively, little to do with the required draught of the team. Fig 131 ^^ ^^^^ ^^ readily understood, however, that more force will be needed for draw- ing a short or blunt plow, like Fig. 131, than one in the form of a longer wedge, as in fig. 132, the latter, like a sharp boat in water, moving more easily. Care must be taken, however, thiit this slender wedge be not too long, else the friction of the sod on the extended sur- face may overbalance the advantage. The cutting part of the plow may be improperly formed like the square end of a chisel, and the sod may slide back- ward on a rise, with a very slight turn, until elevated to a considerable height before inversion ; this must require more force of the team, and make the plow hard 126 MECHAKICS. Fig. 133. to hold, on account of the side pressure. The character of this kind of plow may be quickly perceived by simply ex- amining the mould-board after use ; the scratches, instead of passing around horizontally, as they should do, are seen to shoot upward across the face and disappear at the top. Instead of this form, the point should be long and acute, ■ and the mould-board so shaped as to begin to raise the left side of the sod the moment it is cut, and before the right side is yet reached by the cutting edge. This turning motion being continued, the Bblbrook's Stubble Flow, or Deep Tiller. gQ^ jg inverted by be- ing scarcely lifted from its bed ; and the pressure which turns it being opposite to the pressure of the land-side, an equilibrium of these two pressures is maintained, and the plowman is not compelled to bear constantly to the right to keep the plow in its place. There is, however, an exception, in deep or trench plow- ing, where it becomes necessary to throw the earth from the bottom of a furrow to the top of the inverted sod. A plow of this kind is represented in Fig. 133, which shows Holbrook's deep tiller for stubble land, capable of plowing Fig. 134. a furrow a foot deep, and elevating the earth, which passes lengthwise over the mould-board. A similar Crested Furrow-duxr. foj-m must, be adopted for the rear mould-board of the Double Michigan Plow, so that the lower earth of the furrow may be thrown on the sod inverted by the first or skim-plow. The share should also be so placed as to cut the slice at equal thicknesses on both sides. Some plows are made CRESTED FUBKOW SLICKS. 127 BO as to cut deepest on the land-side, forming a sort of saw- teeth section to the unmoved earth below, and leaving what is termed crested or acute ridges at the top. (Fig. 134.) Such plowing requires as much force in cutting the Fig. 135. -vUV.^ slice, and nearly as much in turn- ing it over, as when level fur- rows are made, and should tliere- fore be avoided. The same result is produced when ^** straight cutter. Laying Lapped Furrows. the plow is improperly gauged, and the plowman is com- pelled to press the handles to tlie left, to keep it from running too much to land. On heavy or clay soils, it is sometimes desirable to place inverted sod in an inclined or lapping position, in order to give more exposure to the crumbling action of the weath- er, and to effect better drainage beneath. Fig. 135 is a section of these lapped furrows. In order to be equally in- clined on both sides, their thickness must be precisely two- thirds their breadth ; that is, if the plow runs eight inches deep, the slices should be twelve ^'s- 136. inches wide. Tiiis mode of plow- ing is controlled by the position of the cutter, wliich should be very nearly upright, as shown in Fig. 135. It has been justly re- marked that the cutter to a plow (Fig. 136,) is almost as important as the rudder to a ship, and if its position be altered, as shown in j^j^ CuUer. Fig. 137, so as to cut under the sod, the furrows will cease to be lapped and will lie flat. This position is desirable in light or loose soils where exposure to the action of the 128 MECHAXICS. air is not desirable, and where it becomes more important to bury com- pletely all veg- etable growth on the surface. If furrows are cut wider in proportion to their depth, The Inclined Cutter, Laying Flat Furrows. thev will be more likely to be laid flat. For example, if the plowing is six inches deep, and the furrows are a foot "wide, the sod will generally dispose itself in a liorizontal or flat position, and this result will be the more certainly secured by giving the form to the cutter already described. Lap- ping the furrows is the common practice in England, but is less necessary for this country, where the moisture of rains dries more quickly, and the severer frosts effect a ready pulverization ; and especially is the practice less needed in thoroughly drained land. The Committee for the trial of implements, appointed by the New York State Agricultural Society, enumerated the following desirable qualities in plows, which every farmer may find useful to examine when he is about to purchase. 1. Pulverizing ])ower. 2. Non-liability to choke in stubble. 3. Lightness of draught, considered in connection with pulverizing power. 4. Ease of holding. 5. Durability. 6. Cheapness. 7. Excellence of mechani- cal work. 8. Excellence of material. 9. Thorough inver- sion and burial of \\eeds. 10. Even distribution of wear. 11. Regularity or trueness of turning and carrying the furrow-slice in sod. OPERATION OP PLOWING. The expert plowman so adjusts his implement that it wUl cut a furrow of just such width and thickness as OPEEATIOU OF PLOWING. 129 may be done with the least draught to the team, and the least exertion to himself. "To secure this end," says Todd, " the team is liitched as close to the plow as it can be and not have the whiffle-trees hit their heels in turn- ing at the corners. As the length of the traces is in- creased, in plowing, the draught increases. Now put the connecting ring, or link, or dial clevis, at the end of the beam, in the lowest notch ; and if it will not run deep enough, raise it another notch at a time until it will run just deep enough. Now alter the clevis from right to left, or from left to right, as may be necessary, until the plow will cut a furrow-slice just wide enough to turn it over well. If the plow crowds the fuiTow-slice without turning it over, it shows that the furrow-slice is too nar- row for its depth ; and the plow must be adjusted to cut a wider slice. On the contrary, if the plowman is obliged to constantly push the furrow-slice over with his foot, if the ground he is plowing be very smooth and even, it shows that there is an imperfection or fault somewhere. Sometimes by adjusting a plow to run an inch deeper, it will do very bad work. And sometimes it is necessary to adjust it to cut a little wider, or a little narrower, before it will cut the furrow-slice as well as it ought to be cut. When a good plow is correctly adjusted, it will glide along, where there are no obstructions, without being held, for many rods. When a plow is constantly inclined to fall over either way, and the plowman must hold it up all the while, to keep it erect, there is either an imperfec- 'tionin the construction of the plow, or it is not adjusted correctly. When a plow " tips up behind" and does not keep down flat on its sole, or when it seems to run all on the point, either the point is too blunt, or is worn off too much on the under side, or there is not " dip enough " — pitching of the plow downwards — to the point. Some- times I have found that a plow could not be adjusted by the clevis so correctly as all the parts were arranged ; and 6* 130 MECHANICS. that by shortening the traces or draught chain, or giving, them a little more length, it -would run like another plow. When a plow is adjusted to run just right, as the point wears off it is necessary many times to give a little more length to the draught chains, or to adjust it with the clevis to run a little deeper. It is sometimes impossible to adjust a plow to run just right with the style of clevis which is on the end of the beam. The arrangement ought always to be such that the draught can be adjusted half an inch at a time, either up or down, or to the right or left. Then if the beam of the plow stands as it should, so that the most correct line of draught wiU cut the end of the beam, it can be most correctly adjusted in a few seconds. " To make a plow run deeper, raise the connecting point at the end of the beam one or more notches higher in the clevis; or lengthen the draught chains. To make it run more shallow, lower the draught a notch or more in the clevis; or shorten the draught chains; or, which should never be done, shorten the back-bands or hip-straps of the harness. To make a plow take a wider furrow-slice, carry the connecting point one or more notches in the clevis to the right hand. A notch or two to the left hand will make a plow cut a narrower furrow-slice. Or, which is seldom allowable, a plow may be made to run more shal- low by putting the gauge-wheel lower, so as to raise the end of the beam. And a plow may be made to cut a nar- rower furrow-slice by carrying the handles to the left hand, or wider by carrying and holding them to the right, beyond an erect position ; neither of which is allowable, except for a temporary purpose." FAST AND SLOW PLOWING. It has already been shown in the chapter on Friction, that the resistance is scarcely increased by velocity, when one body slides over another. The same rule, nearly, ap- FAST AND SLOW PLOWING. 131 pears to apply to force required for cutting the earth, Aud as the friction of the plow and the force exerted in cutting the earth have been found to be the greater part of the whole draught, repeated experiments by the dynamometer have proved that but little increased resist- ance, as an average, occurs when a plow is drawn with in- creased velocity ; the only additional power being that of doing more work in a given time. For example, if a force of 400 lbs. be required to draw a plow, whether at two or at four miles an hour, then twice as much power only is needed to plow an hour at four miles, as at two miles per hour. In other words, no more actual force in amount is necess.'iry in most instances for a team to plow an acre in four hours at the faster speed than in eight hours at the slower. Hence the importance on the score of economy in time, of employing horses that have a naturally rapid gait, provided they possess full strength to overcome the required draught with ease. Fast plowing, however, is better adapted to stubble land than sod. THE DOUBLE MICHIGAN PLOW. The Double Michigan, called also the sod and subsoil plow, possesses some important advnntagos. The forward , or skim plow pares off a sod a few inches in thickness, and inverts it into the bottom of the previous furrow. The second or m.ain plow follows, and throws up the lower soil, completely burying the inverted sod and giving a loose, mellow surfioe to the field. This forms an excellent preparation for all crops, particularly carrots and other roots, which grow best in a deep, loose bed of earth ; and where a portion of the subsoil improves the top-soil by be- ing mixed with it, a permanent advantage results. A greater depth may be attained by the use of this double plow than with one having a single mould-board, in sod ground, because the inversion will be complete even if the 132 MECHANICS. width of the furrow is only one-half the depth. But with a single plow, the width must be considerably greater than the depth, or the „. .„„ . ^ ' Fig. 138. Bod will be thrown on its side or edge and cannot be in- verted. There is one disadvantage, . ° Double Michigan Plom. however, m the use of the double plow. A greater force is required to make two cuts in the soil, one above the other, than one cut with a single share.* For this reason more force must be used to plow a field to a given depth, say one foot, with the double than with the single plow. But the single plow, in order to reach this depth, would re- quire to be so large and to turn so wide a furrow that no ordinary amount of team could be had to do the work. And in addition to this difficulty the inverted surface would not be so well pulverized as by the use of the double plow. THE SIDE-HILL PLOW. Side-hill or Swivel plows -are well known, and are so constructed as to throw the furrow-slice down hill, which- ever way the team may be passing. The mould-board is turned to the right and left alternately for this purpose, the right-hand horse walking in the furrow in one direc- tion, and the left-hand horse in the other. This plow is sometimes used for level land when it becomes desirable to avoid dead furrows and ridges, "without plowing around the field. Fig. 139 represents the swivel plow manufac- * This result has been ijroved by the use of the dynamometer; which lias also shown that a greater amount of earth, in cubic feet, may be turned over with a deep-rnnnin;!; ])low than with a sliallow one, as there is less force expended in cutting the slice when compared with the whole bulk — pi-ovidod the soil is nearly uniform in hardness at different dejiths. THE SIDE-HILL PLOW. 133 Fig. 139. Holbrook's Patent Swivel Plow. tured by F. F. Holbrook & Co., Boston, one of the best in use, and particu- larly valuable for its thorough pulveriza- tion of the soil. One- half of the double mould-board shown in the cut is used for throwing the furrow HoOrook's Swiva or Side-km Flow. to the right, and the other half to the left — the change being effected by passing it under the plow with a single movement and hooking it in place. THE SUBSOIL PLOW. When the common two-horse plow alone is used by farmers, it pulverizes the soil only a few inches in depth, Fig. 140. Subsoil plowing in the furrow of a common plow. and its own weight and the tread of the horses on the bottom of the furrow gradually form a hard crust at that depth, through which the roots of plants and the moisture of rains do not easily penetrate. Hence the roots have only a few inches of good soil on the surface of the earth for their support and nourishment ; and when heavy rains fall, the shallow bed of mellow earth is soaked and injured by surplus water. Again, in time of drought, this shal- low bed of moisture is soon evaporated, and the plants suffer in consequence. But, on the otlier hand, when the soil is made deep, it absorbs, like a sponge, all the rains that fall, and gradually gives off the moisture as it is wanted during hot and dry seasons. For this reason, deep soils are not so easily in- J 34 MECHANICS. jured by excessive wetness, or by extreme drought, as shallow ones. In addition to this advantage, they allow a deeper range for the roots in search of nourishment. Soils are deepened by trench-plowing and by subsoiling. In trench-plowing, the common plow with a monld-board is made to enter the earth to an unusual depth, and to throw up a portion of the subsoil, covering with it the top-soil whicjh is thrown under. A subsoil plow, on the contrary, only loosens the subsoil, but does not lift it to the surface. The Double Michigan Plow, just described, is strictly a trench-plow, and is one of the best implements for this purpose. When the subsoil is of such a character that its mixture with the surface tends to render the whole richer, trench- plowing is best ; but when of a more sterile character, it should be only loosened with the subsoil plow, and more cautiously intermixed with the richer portion above. It often happens that the subsoil plow is very useful in loosening the soil for the purpose of allowing the trench- plow to run more freely through it. The operation o'f the subsoil plow is shown in fig. 140. In using the subsoil plow the less the earth is raised, provided it is well broken to pieces, the easier will be the draught. The part which moves under the soil and per- forms this loosening is of course in the form of a wedge. If the subsoil is dry, hard, and not adliesive, a long and acute wedge will run most easily ; but if the subsoil is stony, a shorter wedge will succeed better. For general purposes it should therefore be of medium length. Difierent modes of connecting this wedge to the beam above have been adopted, each possessing its peculiar ad- vantages. Fig. 141 represents a subsoil plow with a BJngle, broad, upright shank, cutting like a wedge, with THE SUBSOIL PLOW. 135 double edges as well as double points, and capable of be- ■^'^' ^*^' ing reversed when it becomes worn. In light or grav- elly soils this plow runs well ; but where the earth is adhesive and Broad-shank Subsoiler. rather moist, the friction of the two faces of this shank in pressing the Fi". 143. Subsoil plow. compact soil apart becomes enormous, amounting in some cases to more than triple the force required to loosen Fig, 143. the soil below. This plow is there- fore not to be rec- ommended for general use. The objection is in a great measure ob- viated in the plow * shown in fig. 142, where the forward portion of the broad plate is made thicker than the rest. The friction is still further less- ened by employing two narrow shanks, as in fig. 143, Another improvement for lessening friction might be made by using narrow bars of iron or steel, braced and Two-shanked Subsoiler. 136 MECHANICS. connected as shown in fig. 144. The ditching plow, exhibited in fig. 147, is similar in the construction of Fig. 144. this part, and it has been found to work well for siibsoiling, particularly in stony land. If the subsoil hap- Brace-sJiarik SubsoOer. pens tO be filled with roots, the interstices in these plows sometimes become choked — a difiiculty, however, which rarely occurs. In such cases it may be better to employ the plow represented by fig. 141. New subsoil plows have been lately constructed at the West, by which the operations of both plows are perform- ed at once. A saving is thus made in the expense of the implement and in the Labor of one man. In one, known as the Nichols' plow, a flat, triangular blade runs a few inches below the common plow; in Wheatley's, a narrow blade bent like the letter U beneath the plow performs the work. The benefit of subsoiling will last three or four years ; but it is of great importance that land be well under- drained, for if the earth becomes heavily soaked with wa- ter, it settles down into one compact mass, and the advant- ages of the operation are lost. THE PARING PLOW consists merely of a flat blade, which runs beneath the surface, shaving off the roots, but not moving the soil (fig. 145). A shield, shown in the cut, is placed beneath the beam, to regulate the depth of the cutting blade. It is used in cutting turf for burning, and for destroying this- tles and other deep-rooted weeds. "When made light for a single horse, it is sometimes used advantageously for THE GAN(J PLOW. 137 cutting the grass and weeds between vows of badly tilled corn. A two-horse paring plow has been constructed, in which the depth of cutting is accurately regulated by wheels placed on an axle, like those of a cart. The cast- Fig. 145. Paling pLow. iron blade, which cuts about three feet wide, is raised or depressed by means of screws passing through the axle. Its chief utility is in destroying grass and weeds before the sowing of broadcast crops. THE GAXG PLOW consists of three or four small mould-boards placed side by side (fig. 146), and is used for shallow plowing, or for Fig. 146. Gang plow. burying manure or seed on inverted sod, without disturb- 138 STECHANICS. ing tlie turf beneath. In those of the best construction, the depth is regulated by wheels, and the breadth of the fuiTows by turning the cross-beam more or less obliquely, by means of a fixed contrivance for this purpose. The gang plow is liable to become impeded or clogged by stubble, coarse manure, or weeds, and has not come into • extensive use. DITCHrBTG PLOWS. In most localities where tile drains are made, two-thirds of the labor of cutting is loosening the earth with the pick, before shoveling it out. By means of the ditching plow this laborious work is performed by horses. One span, with a good plow made for this purpose, will loosen the subsoil fast enough for eight or ten men shoveling, ' and cutting about 100 rods 3 ft. deep in a day ; or an hour or two each day with the plow will keep two men at work. If the subsoil is very hard, this work should be done early in Bummer, The implement is drawn by two horses, at- tached to the ends of a main whiffle-tree about seven feet long, one walking on each side of the ditch. From one to three times passing will loosen the subsoil five to eight inches, which is then thrown out by narrow shovels, on-, both sides, so that it may be easily returned after the tile is laid, by means of a common plow drawn by the long whiffle-tree before mentioned. There are several modifications of the ditching plow, all accomplishing the same end. The, adjustable ditching plow, (fig. 147,) admits of so great a change in the height Fig. 147. Adjuetable Ditching FUm. DITCHIKG PLOWS. 139 of the beam and handles, that it may be run down in the bottom of a ditch to » depth of four feet. It is, perhaps, the best implement of the kind for all purposes and soils. The movable portion of the beam is attached to the fixed beam by a stout loop and staple, and rises on a oast-iron arc, which passes through it, as shown by the dotted lines. The handles rise on a stiff, wooden arc, (as the dotted lines exhibit,) a piece of thick plankj shown in the small figure on the right, being placed between the handles and fast- ened to them, to render them more firm and steady. The iron work, although light, is braced so as to impart great strength and security. The point is screwed on separate- ly, and is nearly the only pnrt that wears by use. This ditching plow may be used for common subsoiling, the shortness of the share rendering it especially adapted to stony land. Several ditching machines have been constructed for performing the entire operation of cutting the earth and throwing it out, but nearly all of them are too complex for common use. Except in land entirely free from stone, some of their many parts are liable to become bent or in- jured by use, and a very slight derangement of this kind renders them partly or entirely useless. Any ditching machine, therefore, to work well among stone, must be simple and strong, so as to withstand the frequent shocks met with in overcoming obstructions in the soil. MOLE PLOW. The Mole Plow has a wooden beam, sheathed with iron on the lower side, which moves close to the ground, be- low which a thin, broad coulter extends downward, and to the lower end of this coulter a sharp iron cylinder is attached. This moves horizontally, point foremost, through the soil, producing a hollow channel beneath the plow for the escape of the water, the only trace on the surface be- 140 MECHANICS. ing a narrow slit left by the coulter. It is dragged for- ward by means of a chain and capstan worked by a horse, the machine itself being fixed with strong iron anchors. This mode of draining is only adapted to clny soil, free from stone, and although cheaply performed, has been little used since the introduction "of tile-draining. APPENDAGES TO THE PLOW. Wheel Cottlteks. — In soils fi-ee from stones and coarse gravel, and especially on the Western prairies, wheel coulters are found to answer a good purpose, cutting through the turf and roots of grass with great ease, and making a smoother slice than the common cutter. But ■where stones and other obstructions exist, it is necessary to use the simpler, single blade coulter. A good repre- sentation of the wheel coulter is seen on the figure of tlie Moline Plow, on an early page of this chapter. Weed-IIook and Chain. — In turning under large weeds, grass, or other tall vegetable growth, two modes are adopted. One is Fig. 148. the use of the weed hook represented in the annexed cut ; and the other is that of a cliain. The weed-hook has been long known, and is nade in various Weea-Zwok. forms. Sometimes it is bent in the form of a bow with the lower point projecting forward, as in the upper figure; another form is like that shown in the lower cut, pointing backwards. This is less liable to be caught by obstructions. The weed-hook operates on the principle of bending the tall growth forward and prostrate, so that the turning sod completely buries it. The same object is AVEED-HOOK ANI> CHAIN. 141 attained by the use of a heavy chnin; and different modes are used for attaching it to the plow. One of the sim- plest is to fasten one end to the right-hand portion of the main whiffle-tree, and the other to the right handle. In another mode, the chain forms a loop. All these modes of burying vegetable growth are important in turning under clover and other green crops. The weed-hook is usually made of round rod-iron, stiff enough to perform its work, and to possess some spring when it meets with obstructions. Those not accustomed to its use may adjust its position by bending it, until it performs satisfactorily. It is secured to the plow-beam by i)lacing the forward end in a small groove cut length- wise in the under side of the beam, passing a band over it, and wedging until properly secured. Lighter and rnore perfect weed-hooks may be made of steel rod, similar to that used for rake teeth ; they will bend back on meet- ing obstructions, and spring again into position. Such weed-hooks should be made and sold with the other ap- pendages of plows, now that the inversion of green clover for manure has become an essential part of good farming. Sometimes the weed-hook is made to extend at right angles to the plow-beam, curving outwards and down- wards. This form requires- greater stiffness, and small bar- iron is used. No plow will cover weeds or other growth two or three feet high ; but by the use of this hook, the whole is laid completely under the surface. Regulating Wheel. — It has long been a question with plow men whether the wheel under the beam for regula- ting depth is really a disadvantage or a benefit. It is fully'' shown in the able Report by J. Stanton Gould, of the Trial of Plows at Utica, drawn from accurate experiments, that the wheel not only gives better plowing with moderate skill, but that it slightly lessens the draught. Uniformity in the depth of the slice is preserved, without constant 142 MECHANICS. vigilance on the part of tlie attendant; and tliis uniform- ity, by preventing uneven running, lessons the aggregate amount of draught. It is, however, quite important that the wheel sustain little or no pressure ; for as soon as the heam bears upon it, the line of draught becomes crooked at the expense of the team. These facts were established by careful experiments with the dynamometer. PULVBEIZEES. The fine pulverization of the enrth, for the ready ex- tension of the loots of plants, for the action of air on the soil, for the retention of moisture, and for the thorough in- termixture of manure, is of great importance to the farmer. It is but partially accomplished by the plow, which crum- bles the soil only so far as may be done by the act of turning it over. Henoe additional implements are needed for this purpose, among which are the harrow, the cultiua- tor, and the dod-crusher. HAEKOWS. The Uriish-harrow, the original and ludest form of the implement, and still used for covering grass seed, as often Fig. 149. made, is a poor implement. The most projecting limbs are cut partly off, that all m.iy lie flat, but it often happens that the projecting angles of the larger branches plow into the ground and make deep furrows. This Brush-harrow. ^ may be prevented by a careful selec- tion of the small tree which firms the brush, or still better by constructing a simple rough plank frame, so that any quantity of short brush may be pl.iced between two pieces of plank, to admit the tops of the brush to incline down- wards and backwards, being held in place by a few spikes or bolts. Fig. 149. GEDDBS AND SCOTCH HARROWS. 143 The Geddes Harrow is one of the best in use for rough or uneven land. The teeth being situated considerably back of the point of draught, its motion is even and steady, Fig. 150. and easy for the team. In conse- quence of its -wedge-form, it passes obstructions more readily. The center or draught-rod forms a set of hinges, by "which it becomes adapted to uneven ground, or by which it may be easily lifted to discharge weeds, roots, or other obstructions. Or it may be doubled back, and carried easily in a wagon. The accompanying figure (fig. 150) Geddes Harrow. renders its Construction intelligible, without further description. To prevent its Fjg. 151. rising in the middle, as it has been found to do when the draught traces are as short as easy draught requires, the chain is attached to the bar on each side, as shown in fig. 151. The Square Harrow admits of a larger number of teeth, and when made in the best form, efiects thorough pulveri- zation on smootli land, free from obstructions. A modifi- cation known as the Scotch harrow, represented in fig. 152, has forty teeth, inserted in such a manner that each tooth forms a separate track, as shown by the dotted lines. The hinges, as in all square harrows, enable it to fit a rolling or uneven surface, and it may be folded for carrying in a cart or wagon. 'S^'"'=* ■"■ ^s""""* Aarroiu. For the fine pulverization of a smooth surface, a still greater number of teeth has been found to answer an Fig. 152. 144 MECHANICS. excellent purpose, leaving the soil almost as smooth as a garden bed. Tough and sound timber, only two inches square, is used for the frame, and the teeth are five- eighths of an inch square. The Morgan Harrow is an improvement of the Scotch implement, slots being made in the hinges, so that each of the two portions is capable of playing freely uj) and down, as the surface varies, and rendering the rear teeth less liable to follow in the track of the preceding. The draught-iron is made to slide on an iron arc, so that the lines formed by the teeth are controlled at pleasure. It is converted into a broadcast cultivator by inserting flat teeth, the flat portion below being the same in width as above, and pointing slightly forwards. These teeth pul- verize the soil deeply and thoroughly. They are success- fully used for digging potatoes, operating like a large number of potato-hooks, drawn by liorses. The Norwegian Harrow (fig. 153) is a new machine for Fig. l;3. TfoTWEgian Harrow, kept from clogginf^ by tioo C7jlinders oftetlh plo7/insr into each, otkrr. playing into each other. pulverizing the soil, which performs the work in a very perfect manner, by turning up, instead of p.acking down the earth. Two rows of star-shaped tines play into each other, and produce a complete self-cleaning action, pre- venting clogging even in quite adhesive soils. Its com- shares' habkow. 145 plex character and cost have prevented its coming into more genei-al use. Shares' Harrow (fig. 154) is the most perfect of all im- plements for pulverizing the fieshly inverted surface of sward land, to a depth two or three times as great as the common harrow can effect. The teeth being sharp, flat Fig. 154. blades, out with great ef- ficiency ; and as they slope like a sled-runner, tliey pass ^ over the sod, and instead of ^^^fe? tearing it up like the com- mon harrow or gang-plow, and in its place, while the upper surface of the sod is sliced up and torn into a fine, mellow soil. The price of Shares' harrow is about $20, but if furnished with steel teeth, as it should be, it would cost more. (See page 285.) CULTIVATORS. The CtiUivator or Horse-hoe is used for loosening and pulverizing the soil among drilled crops, and for cutting and destroying weeds. A usual form is shown in fig. 155, which represents Holbrook's, one of the best of its kind. The wliecl in front regulates the depth ; the sides may be ex- panded 'or -con- tracted suflJcient- Iv to varv the Holbrook's Horse-Jioe or Cultivator. width from fifteen to thirty-six inches ; they are reversible, eo that the soil may be thrown from or towards the row; and the frame is high enough to prevent clogging with. 7 146 MECHANICS. weeds, stubble, or manure. Various forms of teeth are used, according to the nature of the work, and they are made of steel or cast-iron. The steel teeth, represented in fig. 152, are well adapted for cultivating the rows of Indian com and other hoed crops, where the soil is al- Fig. 136. Claw-toothed cultivator/or hard grtmnd. ready moderately mellow. For harder soils, the teeth should be in the form of claws, as shown in fig. 156, their sharp, wedge-form points penetrating and loosening the earth with comparative ease. An efficient cultivator is made by using both kinds of teeth in the same implement, placing the claws forward for breaking the hard earth, and the broader teeth behind for stirring it. Steel plates, with sharp or " duck-feet " edges screwed at the lower ex- Fig. 157. tremities of the teeth, (fig. 157) are useful for par- ing or cutting the roots of weeds ; and formed like the mould-board of a plow, they are used for throwing the mellow earth toward the row, or, when reversed, from it. Alden's Tliill Cultivator is furnished with fixed thills, extending backwards from the handles. The whole im- plement thus runs with remarkable steadiness and great efficiency, and the driver, by l^earing on the handles, GAEKErr t; iiouse-hoe. 147 readily increases the depth of the teeth, or by bearing to the light or left, guides it in the row. It is not capable of being expanded and contracted in width. GarreWs Horse-hoe, an English invention, is a modifi- ication of the cultivator, and is used for cultivating car- rots and other root-crops in drills, cleaning eight or ten rows at once. It is furnished with sharp, liorlzontal blades, which run beneath the surface, and shave off and destroy all the ^^•eeds within an inch of the rows of young plants. These rows, having been planted by means of a diilling-machine, are straight, and perfectly parallel, and the operator has only to watch one row, and guide the blades for that row, the apparatus being so contrived that the blades for the other rows shall run at the same distance from them. Fig. 158 represents an end view of this implement. It exhibits the apparatus by which the length of the axle is Fig. 153. Garrett's Horse-hoe— En4 vievi. altered to suit all kinds of planting ; by which each hoe is kept independent of the others, so as to suit the ine- qualities of the ground, and by which they can be set any width, from seven inches to thirty. It shows the oblique angle at which thoy run— this obliquity being easily al- 1-18 MECHANICS. tered to any desired degree : this is effected by a move- ment of the upper handle, represented in the figure. By the lower handle, the whole is accurately guided. It is said that two men, one to lead the horse, and the other to guide the implement, will dress ten acres of root-crops in a single day, and tliat it has proved eminently a labor- saving machine. It can be used only on smooth land, free from stone. TWO-HORSE CULTIVATORS are made to run on two ■wheels, and the depth of the teeth is regulated by raising or lowering the frame-work that holds them. They have been much used for pulver- izing the surface of inverted sod, and fitting it for the re- ception of seed, but are likely to be superseded for this purpose by Shares' harrow. Modified so as to pass the two spaces between three rows of corn, they are known as double cultirvators, and have now come into use for cul- tivating large fields, and are generally adopted for this purpose at the West. They accomplish twice the work of the single cultivator. They are of two kinds : those called the sulky cultivators, being furnished with a seat on which the driver rides, and the walking cultivators, without seat, the attendant walking behind. The former will accomplish more work in a day, with less fatigue to the driver ; the walking cultivators are better suited to rough, or sidling ground, and are cheaper. Many manu- facturers make them of different forms, both at the West and ill some of the more eastern States. The best sulky cultivators cost about |75. comstock's eotary spader. This new machine, which has been used to some extent in the broad fields of the West, forks up the soil by means of a series of revolving teeth. It is drawn by two or four horses, according to its size and the strength of the comstoCk's eotart spader. 149 animals, the driver riding on a seat* Sometimes two ma- chines are attached together, and both are driven by one man. It is used only on land free from sod, such as com, or other stubble, and is not adapted to land containing stones or rocks. Its advantages are the following : Greater ease of draught, when compared with the plow, the chief source of friction being the thrusting of tlie teeth into the soil, while the friction of the plow at the moull-bo.ird is usu- ally equal to at least half the weight of the moving sod, added to half the entire weight of both plow and sod, on the sole in the bottom of the furrow, while more force is required to cut with the edge of the share than with the points of the rotary spader. Hence it is found to do twice or three times as much work with the same team as a plow. It does not form a hard crust in the bottom of the furrow, like the plow; and it leaves friable soils pul- verized ready for planting, without the use of the harrow. There are some serious drawbacks to the general intro- duction of this machine. Its cost exceeds ten times that of a good steel plow, while its complexity renders it more liable to strain or breakage, except in uniform and stone- less soils. It cannot be used in wet seasons, and pulver- izes such land only as is previously free from grass. It may, however, prove valuable on extensive farms. CLOD-CEtrSHEES. In clayey soils, clods are often formed in abundance during the process of cultivation. These become very hard in dry weather, and prevent the proper extension of the fine roots of plants in search of nourishment, and also the intermixture of manure with the soil, without which it has been found that two-thirds, or even three-fourths, of the value of manure is lost to growing crops. Different modes of pulverizing the clods have been 150 MECIIAXICS. adopted. The simplest is the " drag-roller" represented in fig. 159. It is made of a log, or portion of a hollow tree, into which a common two-horse wagon tongue has been fitted, by which it is dragged over the ground with- out rolling, grinding to powder, in its progress, every clod over which it passes. The greater the diameter of the log, the less will be the liability of its clogging by gathering the clods before ifc It may also be log, with the round side downward. Fig. 160 represents a similar implc- Fig. loo. ment for one horse; this is used for working be- tween the rows of corn in cloddy grourul. Onp.-horse Clod-crusfier. Tig. 101. The use of these simple implements, by reducing rough fields to a condi- tion as mellow as ashes, has,in some instances, been the means of doubling the crop. It is necessary that the soil be dry when they are used, to pre- vent its packing together. CrossJcilTs Clod-crusher, first used in England, is a more povrcrf .1 and more costly implement (fig. 161). It CrosskilVs Clod-crusher. CLOn-CItUSIIERS. 151 consists of about two dozen circular cast-iroii disks, placed loosely upon an axle, so as to revolve separately. Their outer cireumferenoe is formed into teeth, which ci-ush and grind up the clods as they roll over the surface of the field. Every alternate disk has a larger hole for the axle, which causes it to rise and fall while turning over, and thus prevent the disks from clogging. Fig. 162 represents this implement, as modified and manufactured hi this country. It is used only where heavy clay soils prevail. This clod-crusher can be used only whore the ground and the clods have become quite dry. Even then it packs Fig. 162. American dod-crusTur. the soil, and if followed by a harrow, with scarifier teeth, to loosen it again, it Avonld prove an advantage. It is only in certain seasons that it is most successfully em- ployed, or wlien quite dry weather follows a wet spring. As thorough tile-draining is generally adopted, it becomes less necessary. The best clod-crushers are sold for about $125. THE ROLLER. This implement, now in general use, is employed for pressing in grass seed after sowing, for smoothing the sur- face of new meadows early in spring, and for other similar x52 MECHANICS. purposes. On light soils, it is most vaLiable, and may be used at nearly' all times with safety. Heavy or clay soils will be crusted and injured if rolled while wet. The Fig. 163. 'Field BoUer. roller" was formerly made of a single piece, or of a log of wood dressed to a true cylinder ; but this scraped the earth when turned to the right or left. A great improve- ment was made by cutting the single roller into two parts; and a still greater, by employing cast-iron, in sev- eral sections, as shown in fig. 163. The cost of cast rollers is about $85 to $100. CHAPTER XL PLANTING AND SOWING-MACHINES. Sowing-machines, for wheat and other grains, possess great advantages over hand-sowing. All the seed being deposited by them at a nearly uniform depth, and com- pletely covered with earth, it vegetates and grows evenly, and the plants are uniformly strong and vigorous. A less quantity of seed is required, and the crop is heavier. WHEAT DRILLS. Several excellent grain drills are now manufactured and sold in this country, having much similarity in external appearance. One of the best and most widely known SOWIX3-MACniNES. ir,3 Fig. 164. is made by Blchford & Huffman, of Maccdon, IT. Y. It is represented in the accompany- ing cut, showing eight dropping tubes. The mode by -which the grain is dis- charged from the hopper down these tubes is ex- hibited in section in fig. 103; d being the interior of the hopper, hh a revolving wheel, the projecting rims of which form the bottom of the seed-holder ; the axle at a causes this wheel to revolve, and the small projections on the interior of the rim carry the seed to c, where it drops through an opening in the plate which forms the side of the seed-holder. The rapidity of discharge is perfectly con- trolled by wheel-work, which causes the "axle a to revolve slowly or fast at seed-holder is divided into two parts > a 5, as shown by cross section in figure 166 ; one part, d, containing wheat, barley, and other medium- sized grains, and the other, c, for com, peas, and the larger seeds. This figure shows the opening in the side- plates, through which the grain is discharged. As these two divisions must be used on separate occasions, the Cross-section of Seed- holder. Cross-seciion of Dis pleasure. The by the wheel Fig. 167. £ fr~~Tr asm~'-TSlf S Sliding Reversible Bottom of Hopper. 154 MECHANICS. openings between them and the hoppei are opened and closed at pleasure by a sliding bottom, with a single movement of the hand. This sliding bottom is shown in fig. 167, and forms hoppei-s with sloping sides, down which the grain passes freely. The ends of the tubes, which are shod with steel, are made to pass any desired depth into the mellowed soil, and depositing the seed, it is immediately covered by the falling earth, as the drill passes. This drill is furnished with an attachment for sowing ])laster, guano, or any other concentrated manure, and also with a grass-seed sower. A great improvement has been made in the mode al- ready described, of discharging the seed ; formerly, seed- drills generally were furnished w ith a revolving cylinder, in the surface of which small cavities were made, for car- rying off and dropping measured portions of the grain ; these often broke or crushed the seed, and were liable to derangement. Others were furnished with circular, re- volving brushes, for pressing the seed through holes in the bottom of the hopper ; but this contrivance was im- perfect, and the brushes were liable to wear out. In the discharging apparatus of the drill just described, the seeds are never crushed, and the whole being substantially made of cast-iron, it may be run a lifetime. The best grain drills are sold for $80 or $90. sbtmoue's bboadcast soweb IS an excellent machine for sowing plaster, ashes, guano, salt, or any other concentrated fertilize!', as well as com- mon grain and grass seed. The disagreeable, and even dangerous, as well as heavy and laborious work of sow- ing these manures by hand renders such a machme de- Birable on every farm. It is drawn by one horse, sows COKN PI.ANTEKS. 155 ten feet 'wiJe, and the operator rides in a seat. Seymour's Plaster Sower sows these furtilizers, whether wet or dry. These machines are sold at about $70. COEN PLAXTEES. Among the best one-horse corn planters, which make one drill at a time, are Emery's, Harrington's, and Bil- lings'. The last-named is represented in tlie annexed cut. It drops in hills, eleven inches apart in the row, or, if de- Fig. 108. sired, twenty-two inches, the perfora- tions in the slides regulating the number of grains. It is so constructed as to drop any desired amount of Com Planter. plaster, guano, or other concentrated manure, without coming in contact with the seed. This, and other one-horse drills, are well adapted to ])]anting fields of considerable size, for cultivating in rows but one way. On a larger scale, two-horse drills are employed. Wheat drills are often used for this pur- pose, employing only two of the tubes. Another class of corn planters, for planting in hills, the rows running both ways, consist of hollow tubes, which contain the seed, and which, by striking or pressing on the soil, drop and cover a hiU at one stroke. (See page 285.) tkub's potato planter. For field culture, this implement ha^ proved an import- ant saver of hand labor. It is drawn by one horse, and cuts, drops, and covers the potatoes at one operation. It is usually employed on ground which has been plowed. 156 MECHANICS. and harrowed only, the driver forming the drills by the eye, as the planting proceeds. Straighter rows may be made by first marking the land witli a good corn-marker, and then employing a small boy to ride, directing him to keep the horse on the line. Tho driver has then only to slue's Potato Planter. watch the working of the machine before him. If the ground is rough, or rather dry, it is better to furrow the land previously with a single horse, running the planter in these furrows. For using this machine successfally, tho seed potatoes must be previously assorted, so that those of nearly equal size may be used at a time. It is common to assort them into two sizes, which may be done in winter, or on rainy days. Each potato passes the throat of tho hopper sin- gly ; and if one in a bushel happens to be too large, it will choke the opening. After passing the hopper, each potato is sliced into pieces of the desired size, which then, one by one, drop down the hollow coulter, and are buried. The throat of the hopper is readily contracted or expanded, and adapted to any assorted size of seed. One man, with a horse, will plant several acres in a day, and if the ground be in good order, with nearly or quite HAXD DEILIhS and SEED SOWERS. 157 as much accuracy as by hand, and with more uniformity of depth. HAND DRILLS, OR SEED SOWERS. These are great saTers of labor for sowing the seeds of ruta-bagas, carrots, Fis- iin. field beets, and other farm root crops, besides peas and beans. One of the best in use is HaiTington's, represented by fig. 170, and made by F. F. Holbrook & Co., Boston. The Harrinf/toiVs Hand Seed sower. side chains mark the rows, and it makes its own drill Fis- iTi. drops, and covers the seed with ac- curacy, at one operation. It is readily changed to the hand culti- vator, by remov- ing the dropper, and attaching the Harrington's Hand Ouimator cultivator teeth, ' shown in fig. 171. It then becomes a convenient imple- ment for running between the rows, in small fields. Matthews' Hand Planter is similar in constmction to the above. Allen's " Planet Drill " has a cylindric brass seed-hopper, which revolves with the wheels, . and is readily adapted to seeds of different sizes. It never clogs, and sows and covers readily. 158 MBCHANICIS. CHAPTER XII. MACHINES FOR HAYING AND HARVESTING. MOWIXG AND EEAPING MACHINES. The cutting part of the mowers and reapers made at the present day consists of a serrated blade, as shown by Fi?. I-::). Cuikr-bar. Fig. 174. fig. 173, which passes througli narrow slits in each of the fingers, shown in fig. 173, forming, when thus united, the cutting ap- ])aratus, as ex- hibited in the an- nexed figure, of Wood's Mowing- machine (figure 174). When the machine is used, the motion of the wheels on which it runs is multiplied by means of the cog- wheels, imparting quick vibi-ations, end- wise, to this blade, shearing ofi'the grass smoothly as it ad- vances through the meadow, like a large number of scissors in exceedingly rapid motion. WootVs Mower. The finger-bar, the most important part, now adopted MOWERS XSD EEAPEKS. 159 Fig. 173. in all mowing and reaping machines, was invented hy Henry Ogle, of Alnwick, England, in 1823, and his machine was put in successful operation, after much experimenting, by T. & J. Brown, of that place. But so strong was the prej- udice of the working people against labor-saving machine- ry, that they threatened to kill the manufacturers if they persevered ; and the enterprise for a time was given up.* The limits of this work permit only a brief notice of tiome of the chief points in mow- ers and reapers ; and a few ma- chines are refer- j'cd to, out of a large number of kinds, which are ^^P made in the dif- j fcrcnt States, and which bave proved them- . The Kirby Machine as a Mower. selves worthy of the- confidence of farmers. Fig. 17G. The operation of mowing is shown in fig. 175, which rep- resents the Kirby mower, one of the best single -wheel machines, cutting a swath five feet wide, as fast as the* horses advance. BuOceye Mower with Folded Bar. Various contriv- ances are adopted for lifting or folding the cutter-bar when the machine is not in operation, or in passing from one field » Woodcroft.- 160 MECHAXICS. Fig. 177. to another. A neat and convenient form is used in tlie Buckeye Mower, represented in the accompanying cut, (fig. 176) where the bar is folded over in front of the driver's foet. In the mowing-machine, the cutting apparatus is nar- row, causing the newly cut grass to fall evenly behind it, covering the whole surface of the ground. The reap- ing-machine is simi- lar in construction, with the addition of a j)latform for hold- Kiriy Seaper, with Hcmd Rake. \llS the grain as iti falls, as shown in the annexed figure of the Kirby machine, changed to a reaper (fig. 177). This figure represents the reel, which is attached to, and is worked by the machine, causing the grain, as it is cut, to drop smoothly upon the platform. When a sufficient ■quantity has collected there, it ii swept off by the liand rake, and is afterwards bound in a sheaf. The annexed cut exhibits the Cayu- ga Chief, (an excellent Cayuga Chief— ComMiwa Mower and Seaper. two-wheeled machine) as a reaper, in which the opera- tion of hand-raking is distinctly represented. SELF-EAKIITG KEAPEES. Mowing-machines need but one man for their man- agement, who merely drives the horses that draw it. Fig. 178. SELF-ITAKLya EEAPEES. 161 Reapers, as usually made, require another man besides the driver, to rake off the bunches of cut grain, which is se- vere labor. Various self-raking contrivances have been used to obviate this labor, several of which have been made to do excellent work, and are coming into general use. One of the first successful self-raking attachments to the reaper was that used by Seymour & Morgan, of Brockport, N. Y. It was one of the kind which sweeps across the platform, in the arc of a circle, delivering the ■gavel at the side of the machine. The ordinary reel is used with this class of rakes. An objection to them is, that the grain is seized for throwing off at a point behind the cutters. Owen Dorsey introduced an improvement in the form of what are termed reel-rakes, which strike the grain forward of "the cutters. A series of sweeps or beaters were employed, combined with one or more rake^i, the gavel being delivered from the platform at each cir- cuit of the rake. At first, the horizontal motion of these arms prevented the driver from riding on the machine. An improvement was ef- fected, so that the arms and rakes, after passing the platform, were made to rise to ancarly vertical posi- tion, thus passing the driver freely. The accompanying engraving, (fig. 179) representing the selt- raker used on the KJVby machine, shows the position of the arms when in motion — one of them serving as a rake at each revolution. There are several modifications of this class of rakes, made by different inventors. Marshes machine consists of beaters and rakes combmed, and de- rig. ITD. TJie Kirby Sdf^raleer. 162 MECHANICS. livers one or more gavels at each revolution, according to the number of rakes used at a time, Johnsoii's rake is furnished with rake-heads for each of the arms, which are 60 arranged aa to dip low into the grain forward of tlie cutters, and afterwards to rise in passing over the plat- form. To discharge the grain, the driver uses a latch- 1 cord and lever, so that the path in which the rake travels is changed by opening a switch or gate, permitting one of the rakes to pass low enough to sweep the platform. The Cayuga Chief, Buckeye, Hubbard, and other reapers, use this self-raker. The Kirby machine employs a self-raking attachment of its own, already represented in fig. 179. Two or three of the arms, or beaters, at the option of the driver, bring the grain on the platform ; the other one or two carry the rake-head. The driver may throw off a gavel, or two gavels, at eacli revolution; or the rake may be made to run continuously, at regular intervals, without attention on the part of the driver. The arms, or rakes, are so made as to be adjustable to the height of the graia, The Dropper is a simple contrivance, (represented in the annexed en- graving) consist- ing of a light plat- form, which holds the grain until the gavel is large enough, when it suddenly drops and discharges it. It is much used at the West, and, al- Cmjuga chief wllhDropper. though hardly so perfect as some self-rakers, is preferred by many farmers, the gavels being delivered behind the machine, and thus keeping the binders up to their work, in clearing the way for the next passage of the reaper. rig. 180. marsh's harvester. 163 BINDERS. Several machines for binding grain have been invented^ possessing considerable merit, but so far they do not ap- pear to be adapted to general introduction. -Mire's Marmster, imicTi used at the West, is so con- structed, that two men may readily bind as fast as the harvester does its work. The binders stand on a small platform, furnished with a guard or rail, and the grain, as fast as it is cut, is carried up by an endless apron to a platform, where each man alter- nately makes his band, and receives and binds his sheaf. As they expend no time in stooping, or in passing from gavel to gavel, they are enabled to work with case and rapidity. The weight is only that of one man more than on a hand-raker. (See page 286.) Saaders arc reaping-machines employed for cutting the heads of wheat with a small portion of the straw, leaving most of the straw standing. They are usually driven by four horses, and are thrust forward ahead of the team. A two-horse wagon, in addition, is driven along side, to re- ceive from an endless apron the heads, as they are cut by ' the reaper. They are only used on the extensive fields of » the West, and a difference of opinion prevails as to their general value. DURABILITT AND SELECTION. Mowinresent a soft and uniform re- sistance, and hence, well-made machines will last several years without much rejoair. The Report of the Auburn trial of mowers and reapers gives five years as the aver age " lifetime " of tliese machines. Much will depend on the amoimt of work performed in a season ; an extensive farmer states, that be usually cuts about five hundred acres with each machine before it needs renewing. Much, also, depends on the care which the machines receive ; such as keeping them always well sheltered from the weather, and thoroughly cleaning every part, and care- fully wiping the journals and bearings before they are laid aside for the season. In selecting mowers and reapers, there are several points which the purchaser should carefully observe ; as, for example — 1. Simplicity of construction. 2. Use of best material for knives and other parts used in manufac- ture. 3. Finish and perfection of gearing and running parts. 4. Durability, as proved by use. 5. Ease of draught. 6. Freedom from side draught. 7. Quality of work. 8. Ease of management. 9. Convenience and safety of driver. 10. Adaptation to uneven sur- faces. A part of these points can be fully determined only by thorough trial ; and it is always safest to purchase of those manufacturers whose machines have been long enough in general use to establish their char- acter in these respects. Fortunately, there arc many in different parts of the country, who have secured a good reputation, from whom machines, or parts for repairs, may be obtained without sending long distances. The report of the Auburn trial, in 1866, states, that out of twenty different mowing-machines, which were tried on a rough meadow, every one, with two exceptions, " did good work, which would be acceptable to any fanner ; and the HAT TEDDERS. 165 Fi?. 183. appearance of the whole meado-w, after it had been i-aked over, was vastly better than the average liand mowing of the best farmers in the State." Since that trial, a con- tinued improvement in manufacture lias been taking place, and the machines are becoming more perfect. The price of a good two-horse mowing-machine is about $120 ; and of a combined mower and reaper, about 8170. HAT TEDDISG MACHHTES. Machines for stirring up and turning the drying hay have long since been known and used in England, and a few were introduced into use in this country. But as they were heavy and cumbersome, they nevei* came into common use. A few years since, ___ -lifHS Bullard'sHayTed- -^^^^^ff der was invented, and has been wide- ly used. It scatters and turns the hay with great rapidi- ty, and consists of several forks, held nearly upright, hut worked by a com- pound crank, so as to scatter the hay ,, „ ^, Bullard^ Ray Tedder. m the rear of the machine. The close resemblance of the movement of these forks to the energetic scratching of a lien presents a ludicrous appearance to one w'lo sees it for the first time. The use of the tedder is found greatly to hasten the drying process, especially on heavy meadows, and to enable the farmer to secure his hay in so short a time as frequently to avoid damaging storms. 166 3Il:(IIAN'ICS. A new maehino, remarkable for its simplicity and [ler- fection of working, is the American Hay Tedder^ made by the Ames Plow Company, of Boston. It is repre- sented in the accompanying cut. It is furnish- ed with sixteen forks, attached to a light reel in such a manner that they re- volve rapidly, with a rotary, continuous, and uniform motion. It never clogs, may be easily backed, ond roadily passes over ordinary obstruc- tions, without any attention on the part of the driver. Hay tedders should be used on the meadow about three times a day, which will enable the farmer to cut his crop in the morning, and draw it in the same day ; giving him, also, more uniformly dried, and better hay. The price of hay tedders varies from $75 to $100. 71te American Ihrj Tedder. HOESE lIAY-KAKEa. The simplest and original form of tlie horse-rake is represented in fig. 184. It was made of a piece of strong sctmtling, three inches square, tapering slightly toward the ends, for the purpose of combining strength w\\h. lightness, and in which were set horizontally about fif- teen teeth, twenty-two inches long, and an inch by an inch and three-fourths at the place of insertion, tapering on the under side, with a slight upward turn at the points, to prevent running into the ground. The two outer teeth were cut off to about one-third their first length, and draught-ropes attached. If these pieces were HORSE HAY-RAKES. 167 too short, the teetli were hard to guide ; if too long, the rake was unloaded with difficulty. Handles served to guide Fig. 184. Simple Jiorse-rake. the teeth, to lift the rake from the ground in avoiding ob- structions, and to empty the accumulated hay. In using this rake, the teeth were run flat upon the ground, passing under, and collecting the hay. When foil, the horso was stopped, the handles thrown forward, the rake emptied and lifted over the windrow thus formed. The windrows, as in other horse-rakes, were made at right angles to the path of the rake, each load being de- posited opposite the last heap formed, in previously cross- ing the meadow. A few h< lurs' practice enabled anyone to use this rake without difficulty; the only skill required was to keep the teeth under the hay, and above the ground. In addition to raking, this implement was employed for sweeping the hay from the windrow, and drawing it to the stack. It was also useful for cleaning up the scattered hay from the meadow, at the close of the work ; for rak- ing grain-stubble, and for pulling and gathering peas. If made of the toughest wood, and with the proper taper in the main parts for lightness and strength, according to the principles already pointed out in a previous chapter, it was easily lifted, and its use not attended with severe labor. 1C8 MECHANICS. This simple liorse-rake has nearly gone out of use, and yet, on account of its simplicity and cheapness, it is wor- thy of being retained on small farms, and especially on meadows with uneven surfaces. The cost need not be more than three or four dollars. From twelve to fifteen acres could be raked with it in a daJ^ The Bevolving Horse-rake {Zg. 185) was next generally adopted, possessing the great advantage of unloading Fig. 185. Revolving Horse-rake ■without lifting the rake or stopping the horse. It has a double row of teeth, pointing each way, which are brought alternately into use as the rake makes a semi-revolution at each forming windrow, in its onward ])rogress. They are kept flat upon the ground by the pressure of the square frame on their points, beneath the handles ; but as soon as a load of hay has collected, the handles are slightly raised, throwing this frame backwards, off the points, and raising them enough for the forward j'ow to catch the earth. The continued motion of the horse causes the teeth to rise and revolve, throwing the back- ward teeth foremost, over the windrow. In this way, each set of teeth is alternately brought into operation. The cost of this rake is from $7 to $10, and twenty acres or more could be raked with it in a day. A further improvement has been made in the revolving ral:c, by attaching it to a sulky, on which the operator REVOLVING IIOESK-EAKES. 169 rides, enabling him to do a larger amount of work with less fatigue. There are several modifications, some of ^'s- '^"- which place the rake in front of the sulky- wheels, and others, in the rear. One of , the best and most widely used is " Warner's Sulky Revolver," manu- factured by Bly- myer, Day & Co., of Mansfield, Ohio, and by others. It is represented in the annexed cuts, fig. 186 showing it in the operation of raking, and fig. 187, the same machine, with the rake thrown upon the wheels, for driving from field to field. The head is the same as the com- mon revolving rake- head — the teeth be- ing tipped witli mal- leable iron. The rake is operated by means of a lever, at- tached to a journal at the centre of the rake-head. By means of cams, stop, and spring, the lever and head are entirely at the will of the operator. A slight pressure, equal to seven or eight pounds, on a lever, causes the rake to revolve ; and it is also readily elevated for back- ing, or for passing obstructions. These rakes are now generally superseded by the lighter and more effective steel-tooth rakes described on the fol- lowing pages. 170 MECHANICS. SPRIN(J-TOOTH RAKE. Fig.] The original form of the spring-tooth rake is shown in fig. 188. The teeth were made of stiff, elastic wire, on thepoints of which the rake ran, and not on the flat sides, as in those already described. TJiey bent in pass- ing an obstruction, and sprung back again to their place. This rake was un- loaded by simply lifting the handles, which was easily done, the rake be- yprlns-tooth Hjrse-rake. Jjjg ]ig|^^^ ^^^ about one-half the weight being sustained by the horse. All the spring-tooth rakes made and used at the present time are attached to wheels, and a seat is furnished for the driver. There are many patented modifications, some possessing advantages of greater simplicity, or ease of management ; but all appear to be good and efficient rakes, enabling the operator to gather about twenty-five acres in a day. These teeth are made in the form of a semi-circle, with the ends pointing forward, and the gathering hay accu- mulates in the concave space formed by their curvature. "When well loaded, the operator, with a slight movement, raises all the teeth together, and the hay is dropped at the winrow. In some rakes this is effected with the simple pressure of the foot j in others, a h^nd-lever is employed. THE HAT-SWEEP. 171 The use of steel-tooth rakes- reduces materially the cost of the crop in the great saving of labor ; a boy can effec- tively accomplish the work of many men using the old implements. Not only are these rakes valuable for col- Fig. 189. lecting hay, but are successfully employed for gleaning grain stubble. They are also especially useful in raking up rowen. Their present cost is about 130. The above cut, fig. 189, represents the style of steel-tooth rake made by Wheeler, Melick & Co., Albany, K Y. THE HAT-SWEEP. Where the hay is secured in stacks, or in hay-barns situated contiguous to the meadow, the use of the hay- sweep, in coimection with the horse-fork, would probably Fig. 190. enable two or three men, and two boys, with three horses, to draw and pack away thirty tons a day, or more. The hay-sweep, invented many years Bay-Sv>eep. ago by W. R. Smith, of Macedon, N. Y., is but little known. The acconipanpng figures (190 and 191) exhibit its construction and use. It is essentially a large, stout, coarse rake, with teeth pro- 173 irECHAXICS. jecting both ways, like tliose of a common revolver ; a horse is attached to each end, and a boy rides each horse. A horse passes along each side of the windrow, and the two Fig. 191. Hay-mie^ in Operation. thus draw this rake after them, scooping up the hay as they go. When 500 pounds or more are collected, they draw it at once to the stack, or barn, and the horses turn- ing about at each end, causing the gates to make half a circle, draw the teeth backward from the heap of hay, and go empty for another load — the teeth on opposite sides being thus used alternately. To pitch easily, the back of each load must be left so as to be pitched first. The dimensions should be about as follows : — Main scantling, below, 4 by 5 inches, 10 feet long ; the one above it, same length, 3 by 4 inches ; these are three feet apart, connected by seven upright bars, 1 by 2 inches, and 3 feet long. The teeth are flat, 1|- by 4 inches, 5 feet long, or projecting 2^ feet each way ; they are made tapering to the ends, so as to run easily under the windrow. A gate, swinging half way round on very stout hinges, is hung to each end of this rake, and to these gates the horses are attached. Each gate consists of two pieces of scantling, 3 inches square, and 3 feet long, united by two bars of wood, 1 by 2 inches, and a third, at the bottom, 3 inches square, and tapering upwards, like a sled runner; HORSE IIAY-FORKS. 173 these runners project a few inches beyond the gate. The whifSe-trees are fastened a little above the middle of the gate, and should be raised or lowered so as to be exactly adjusted. This machine may be made for $G or $7. In using, not a moment is lost in loading or unloading. No person is needed in attendance, except the two small boys that ride the horses. If the horses walk three miles an hour, and travel a quarter of a mile for each load, they will draw 12 loads, or three tons an hour, or thirty tons in ten hours, leaving the men wholly occupied in raising the hay from the ground, by means of another horse, with the pitchfork. It will be obvious, that this rapid mode of securing hay will enable the farmer to elude showers and storms, which might otherwise prove a great damage. IIOESB IIAT-FORKS. Every farmer who has ever pitched off from a wagon in one day ten or twelve tons of hay -pig. 190. is aware that no labor on the farm can be more fatiguing. The horse- fork, in its various forms, which, to a considerable extent, has been brought into use, has afforded great relief, severe labor being not only avoided, but much greater expedition attained. The effective force of a horse is, at least, five times as great as that of a stout man ; and if half an hour is usually required for him to unload a ton of hay, then only six minutes would be necessary to accomplish the Same result with horse-power. Actual experiment very nearly accords with this estimate. '^^"^ iiorsefork. A simple form of the horse pitchfork was described in 174 MECHANICS. the Albany Cultivator, in 1848, from which a suhscriber in Bradford County, Pa., made the first used in that re- gion. Some years later, he stated that there were at least two hundred in use. The preceding figure represents this simple and original fork. A is the head, twenty- eight inches long, and two and a half inches square, made of strong wood. ^ G' is the handle, five and a half feet long, mortised into the head, with an iron clasp or band of hoop iron fitting over the head, and extending six inches up the handle, secured by rivets. The prongs of the fork are made of good steel, one- half an inch wide at the head, twenty inches long, and eight inches apart, with nuts to screw them up tight. Rivets are placed on each side of the middle ones, to prevent the head from splitting. The rope is attached to staples at the ends of the head. The single rope D extends over a tackle-block, at- tached to a rafter at the peak of the barn, about two feet within the edge of the bay. The rope then passes down to the bottom of the door-post, under another tackle- block, and to the outside of the barn, where the working horse is attached to it. A small rope or cord G is attached to the end of the handle, by which it is kept level, as it ascends over the mow. The cord is then slackened, and PilcMng Hay Ihrauyh a Window wilh Horse-power. GI.ADDING S HORSE-FOKK. 175 the hay tilts the fork, discharging its load. The horse is then backed up, ready for anotlier fork load, the only labor of the workman being to drive the fork into the hay and keep the cord steady. An important advantage is gained, besides the saving of time ; for the man on the load, being relieved from the severe labor of pitching, is fresh and vigorous for throwing on another load in the field. The length of the handle made it difficult to use this fork under low roofs, and an improvement was made by Glad- ding, by which the head of the rake only was tilted, leaving the handle in its horizontal position. A hinge- joint is placed at the connection of the licad and handle, so that, at any moment, by a jerk on the cord which passes up a bore in the handle, the fork is dropped, as shown in fig. 194, and its load depos- ited. This may be done instantane- ously, at the mo- ment it happens to be swung to the most favorable spot. Its weight causes the head to fly back of its own accord, and resume its former position, ready for another forkfuL The rope suspending the fork should be fastened to the highest portion of one of the rafters, over the mow, and a smooth board should be placed, vertically, against the face of the mow, for the hay to slide on as it ascends. By attaching this rope in front of, and within a window, the hay is carried with ease into the window, and thus lofts over sheds, carriage- houses, etc., where the old horse-fork could not be used, are filled by the use of Qladding's improvement. This is one of the best forks, adapted to all kinds of pitching, Gladding's Jlay-fork. 176 MECHANICS. and has unloaded a ton of hay in about three minutes; and over a beani twenty-two feet high, under a low rafter, in about nine minutes. In using horse forks, as already stated, their operation is much facilitated by providing a board slide, to be placed vertically against the face of the mow, or bay, on which the hay moves upward. In pitching into a win- dow, the bottom of this board slide should be placed out a few feet from the building, and the top should rest on the base of the window. When convenient, the back end of the wagon load should be placed towards the win- dow. There is no limit to the height at which the pitch- ing may be easily performed — giving the use of the horse-fork a great advantage over hand pitching ; and barns, with high posts, may be built for the storage of hay. Other forms have been adopted for pitching under roofs, by using shorter handles. One of the best is Palmer's Fig. 195. Pi'', ion. Palmer^ 8 Fork. Fork., made by Wheeler & Co., Albany, and Palmer & Co., DOTTBLE FOEKS. 177 Chicago, which is represented in the accompanying figures, Fig. 197. Fig. 198. the right-hand one showing its posi- tion when ascend- ing, loaded with hay ; the left-hand, •with the knee-joint brace contracted, by jerking the cord for emptying the load. Still another, known as Myers^ ElevvtoT, is shown in fig. 197, in its Myers' Hay Elevator. position when lift- ing the hay, and fig. 198, when dropping it. The head is iron, and it is a strong and simple fork. DOUBLE FOEKS. The double forks clasp the load of hay like the claws of a bird. This class ^'g- "S- of forks may be used for pitching over a beam, with- out a board facing. They are better adapted to pitch- ing short straw, especially those which like Ray- f mond's,have sever- \ al teeth; but more time is required for thrusting in the two forks than one. One of the simplest is Bearddey'a Hay Elevator, (fig. 199) 8* 178 MECHANICS. which sufficiently explains itself. Fis. 800. Baymmd's Forh. mond's ISlevator, made hy J. II. Y., consists of two three-pronged forks, connected together by a hinge, (fig. 200) and is one of the best double forks. Connected with this fork is a ready con- trivance for attaching it, in a moment, to any rafter or beam. Tlie accompanying figure (fig. 201) represents the clamp by which this attachment is effected, and fig. 200 shows the elevator, secured in position from two points, with the forks opened, when dropping their load. It is raised and lowered by the double ropes passing over the two fixed pulleys, and the one on the elevator — the horse moving twice as fast as the load is raised. Thus attached to two beams, the The "Little Giant" Fork resembles the claws of a bird, and has a fluted, tubu- lar, cast head, the single grasping- tooth being double- jointed, and per- mitting it to enter the grain freely. On the movement of the horse, it is brought to its place, grasjnng its load firmly. Hay- Chapman, Clayville, N, Fig. 201. Grappling Irons and Hoisting l'a*Me. load may be run hori- HARPOON FORKS. 179 zontally, as well as raised vertically, as more fully ex- plained under the liead of Stacking. By the single fasten- ing, (fig. 201) the fork is only raised vertically. HAEPOON FORKS. For pitching hay exclusively, or any material which hangs well together, the harpoon forks do their work more rapidly than any other, but they are not adapted to Fig. 205. Fig. 204. Walker's Harpoon Fork. Sprouts Fork. short straw. Walker's harpoon, made by Wheeler,Melick & Co., Albany, is a straight bar of metal, appearing al- most as simple as a crow-bar, (fig. 202. Its point is driven into the hay as far as desired, when a movement at the han- dle is made, which turns up the point at right angles, (fig. 203,) enabling it to lift a large quantity of hay. A modifica- tion has spurs, which are thrown out on opposite sides. The combined fork and knife invented by Kniffen «fc Har- 180 MECHAinCS. rington, of Worcester, Mass., is an excellent Lay-knife, when folded, as in fig. 205, and an efficient elevator, when opened, as in fig. 204. It is well adapted to the use of farmers who have nothing but hay to pitch, and plenty of room for the elevator to swing in. At the Auburn trial, this fork discharged a load of hay weighing twenty-three hundred pounds, over a beam, in two minutes. The prices of horse-forks, of different kinds, vary from $10 to $20. HAT CAEEIEES. An inconvenience results from the fixed position of a hay-fork, preventing the hay from being distributed over different parts of a broad bay, except so far as it may be swung to the right or left, and the load dropped at a sig- nal. Several hands are sometimes required to spread this hay evenly, as it is rapidly discharged by the horse-fork. Another disadvantage is, the required narrowness of the bay, which cannot well be more than twenty or twenty- five feet wide. These objections are obviated, and the hay carried fifty or a hundred feet horizontally, by means of Side's Elevator and Carrier, of which the following clear and full description is given in the Report of the Auburn Trial of Implements : — " It consists of a track, made of 2 by 5-inch plank, fastened to the rafters a few ^jiches below the ridge of the barn by l^inch square strips and twelve-penny nails. Upon this track runs a car; a rope passes through it, and through a catch pulley attached to a horse hay-fork, then back to the car ; the other end passes back to the end of the bani, and returns through pulley wheels to the bam floor, to "which end a horse is attached. By a peculiar arrangement of the car, it is held in posi- tion on the track, over the load to be unloaded, until a forkful of hay is elevated to it, when it is liberated from HAT CAEEIEKS. 181 its position, and the fork made fast to the car in one oper- ation, then it moves off on the track very easily, and any distance you may choose to have it canied ; the operator, by pulling a coid, trips the foi"k, and the horse, turning around, walks or trots back to the [jlace of starting ; the car is pulled back to its position by the trip cord, when the fork descends for another load. The fork comes back so easily and quickly that the horse can be kept in motion continually, elevating from 300 to 400 pounds of hay, and carrying it forty to fifty feet in a horizontal direction, and returning for another load in less than a minute. Its advantages over the old mode are : 1st. — The hay can be carried into the second, third, and fourth bays from the wagon, as easily as into the first, • thus saving a large amount of labor in the mows. 2d. — ^The hay is elevated perpendicularly from the load, thus obviating the friction caused by dragging the foi'kful of hay over and against the beam ; also the danger of tripping or breaking the fork as it is drawn over the beam. 3d. — The car and fork return so easily, the fork drop- ping in the middle of the load, ready to be thrust into the hay immediately ; whereas, in the old method, it is very hard work to get the fork back, if the hay has been car- ried any distance. 4th. — The horse turns around, and walks or trots back to the place of starting, instead of backing, thus gaving much labor to both horse and driver, 5th. — The hay need be elevated only high enough to clear the highest beam, when it can be carried horizon- tally, until the mows are more than half full, when, by shortening a rope, the fork can be made to pass along only sixteen inches below the very peak of the barn. 6th. — It requires but very little force to carry the hay horizontally, whereas, by the old methods, it requires more force to carry it horizontally than to elevate it. 183 MECHANICS. 7«A. — By extending the track four feet beyond t'he end of the building, hay can be elevated and carried into long, low hovels, or cow barns, when no other arrange- ment would work at all. The car is small, and the track light and simple ; a weight has been lifted of 1,080 pounds by it at one time, with a pair of mules." By using a strong car, it may be employed for unload- ing coal from a boat. Building Stacks. — Three long polos may be used for this purpose, securely chained at the top, and spread in the form of a tripod. The one to which the lower pulley is attaclieil should bo set firmly into the ground, to pre- vent displacement by the outward draught. Holes are bored into the poles at convenient distances, and cross pieces secured to them, for holding the boiird slide, and permitting it to bo gradually raised, as the stack goes up. The hay may be pitched from the ground as well as from a load, without inconvenience, to any height. Instead of chnining the poles to- gether, they may be firmly secured by using two stout clevises, the bolts of «hich are passed through Mode of Cmpling tfu Poles. ^^^^^ j^^j^^^ ^^^^. ^^^ ^^^^^ ^^^^ of the poles, (fig. 206). Palmee's Hay Stacker, represented in fig. 207, has been much used at the West, where large quantities of La.y are deposited out of doors. It'first elevates the hay, and then swings it around over the stack, dropping it where desired. It does not drag the hay against the side of the stack, requires no staking down to prevent tipping, and is easily drawn on the sills as runners, to any part of the farm. The horizontal motion of the crane is TALMEE'S HAT STACKER. 183 FiS. 207. effected as folloTvs : — Two ropes are attached to tlie wliiffle- tree, one, a strong one, to elevate the hay, running on the pulleys at B, C, and JD ; and the other, a smaller one, pass- ing the swivel pulley at A, on the end of the lever B, extending from the foot of the upright shaft. This cord then passes up and ' over a pulley above the weight E. The "weight is about four pounds, nnd is attached to the end of the smaller cord. At the same time that the horse, in drawing, elevates the fork with its load of hay, the weight E is raised until it strikes the pul- ley, wiien the power of the horse becomes applied to the end of the lever B, causing it to revolve, and swing the hay over -^^^^^^^MU****- the stack. As the PiAmer-e my SiMlm. horse backs, the weight drops again to the ground, taking up the slack rope from under the horse's feet, and the weight of the fork causes the arm of the derrick to revolve back over the load. The intended height for raising the hay, before swinging, is regulated by length- ening or shortening the smaller cord, as the arm will not revolve until the weight strikes the pulley under the head block. T. G. & M. W. Palmer, of Chicago, own this invention, and furnish the smaller parts of the ma- chine, the heavier being easily made on the farms where intended to be used. Fig. 203 shows the manner in which Eaymond's Ele- vator is mounted for stack building. These poles need not be so heavy as when three poles alone are used. They are kept from being drawn over towards each other in 184 MECHAKIOS. elevating heavy leads, by lashing tlie lower end of each outer pole to a strong stake, driven into the ground obliquely, by first making a hole with a crow-bar. It is convenient to place the two pole tripods sufficiently dis- tant from each other to give room for the stack, or rick. Fig. 308. Farlc cm, Poles far Building Slacks. and to allow the wagon to pass within them. The eleva- tor first lifts its load, and then carries it along the rope, till the man on the load drops it by a jerk of the cord. This apparatus is made by J. H. Chapman, of Clayville, N. Y. HAY PRESSES. Among the best Hay Presses in the country is the one manufactured by L. & P. K. Dederick, Albany, and rep- resented in the annexed engraving. It is worked by one or two horses, operating with great force by means of the arms on each side, which are connected with toggle- joint levers, explained in a former part of this work. The hay is thrown in from the upper platform, and when re- duced to compact bales, by means of the powerful force which this press gives, is taken out at the lower. In order to prevent the necessity of the horses running back at dederick's hay press. Fi?. 209. las DedericKs Bay Press. the pressure of every bale, Dederick's patent capstan (fig. 210) is employed with this press. Fig.sio. The horse or horses, in passing around, wind up the rope on a horizontal wheel or drum. The possibility of any accident by slipping backwards is prevented by the pawl or anchor, U, at the end of the lever, ■7 ' When the 186 MECHANICS. pressure is completed, the driver touclies the upright rod, and detaches the •wheel or drum, by which the rope is drawn backwards, without stopping the horses, which continue to walk around the circle. This capstan answers an admirable purpose in using the common horse hay-fork, by obviating the necessity of ^ backing up at every forkful. The New Tork Beater Press Company, of Little Falls, manufacture a press, working like a pile engine, and re- ducing the hay to a degree of compactness nearly equal to that of solid wood. These bales are well adapted to long conveyance by land or shipment to foreign ports. Hat Loaders. — Several of these, of different construc- tion, have been tried to a limited extent, but, so far, the experiments have been but partially successful, or the machines have not proved themselves fully adapted to general use. Their expense, when compared with the hovse- fork, and, to some degree, their cumbersome character, have proved objections. They mostly require very smooth meadows, are often difficult to work in the wind, and those coiisti'ucted on the endless-rake principle are found to carry up small stones or gravel into barley, endangering the thrashing machine. Further ingenuity and labor on the part of inventors appear to be required, to place them generally within the reach of farmers. CHAPTER XIIL THRASHING, GRINDING, AND PREPARING PRODUCTS. THKA8HING MACHINIiS. The old mode of beating out grain with the hand flail, (fig. 211,) has now nearly passed away, and thrashing machines liave come into general use. VAirE OF THKASniNG MACHINES. 187 S. E. Todd makes the following statement relative to the saving of labor effected by these machines : " I have thrashed a great deal of grain of all kinds, with my own Fig. 211- flail ; and I have talked with others who have been accustomed to thrash their grain with flails, and I have come to the conclusion thr.t the following figures rep- resent a fur average as to the quantity of grain that an ordinary laborer will be able to thrash and clean in a day, viz. : Seven bushels "jm oidMail^ "" of wheat, eighteen bushels of oats, fifteen bushels of barley, eight bushels of ryo, and twenty bushels of buckwheat. In order to make this more intelligi- ble, it will be necessary to double the number of bushels that one man is able to thrash, as two men will be requir- ed to clean the grain with a fanning mill. "In order to labor economically and advantageously with a thrashing machine, two horses, at leagt, and three men are necessary. In most instances four or five men will be required, which will make a force equal to fifteen men with flails. Such a gang of hands, and two good horses, with such a thrasher and cleaner ns Ilarder's, are capable of thrashing and cleaning of the same kind of grain to which allusion has been made, one huridi'ed and seventy bushels of wheat, three hundred and twenty-five of oats, two hundred and twenty of barley, one hundred and eighty of rye, and two hundred and sixty of buck- wheat. Some manufacturers of thrashing machines fix the average day's work higher than these figures. In some instances, I will acknowledge that a span of horses and five men can do much more than the amount repre- sented by the foregoing figures ; yet I am satisfied that in the majority of instances they will not thrash and clean a greater number of bushels than I have indicated. But, 188 MECHANICS. even at the low figures that I have recorcled, such a ma- chine as Harder's, or Palmer's Climax, or Wheeler, Melick & Co.'s, will be found to be a great labor-saving machine for thrashing all kinds of grain. "There is one consideration that should not be over- looked in this estimate, which is the much greater amount of labor performed, with far less fatigue. When one la- borer can perform the work of two or more workmen with less fatigue than has usually been required, a great point is gained." J. Stanton Gould, estimating from a large number of statements that a saving of five per cent of the grain is effected by using the machine, over thrashing by the flail, computes the aggregate annual saving in the United States to be over eight million bushels of wheat, two million of ryC; eight million of oats, and nearly a million of barley. For farms of moderate size, the endless-chain powers for driving thrashing machines are most convenient, being fig. 212. Endiess-ckatn horst-power, driving a thrashing-machine. compact or requiring but little room, easily conveyed from one place to another, and readily applicable to sawing wood, cutting straw, and to various other purposes. Fig. 212 represents a single horse-power, driving a small thrash- ing machine, with a simple, horizontal separator and straw TO MEASURE ENDLESS CHAIN POWER. 189 carrier. Endless-chain powers are now extensively manu- factured and largely used throughout the country on farms of moderate extent ; and requiring but little pre- paration and few men to attend them, they enable the farmer to do his threshing or to cut his feed at any con- venient time, besides . their occasional use in driving the circular saw, pumping water, grinding feed, or other work performed by stationary power. On large farms, the rapid introduction of farm steam-engines (of which there are now several admirable styles) is relieving the severe horse-labor required to move heavy machinery, and giving the farmer better control of his work. The power of these machines, and the amount of fric- tion in running them, may be easily ascertained by the rule, already given in a farmer part of this work, for de- termining the power of the inclined plane ; for the only difEerenee between the endless chain and a common in- clined plane is, that in one the plane is fixed, and the body moves up its surface, and in the other the plane itself moves downward, and the weight or animal upon it re- mains stationary. The same principle applies in both cases. First, to ascertain the friction, let the platform^ be placed on a level, with the horse upon it; then gradually raise the end until the weight of the horse will just give it mo- tion. This will show the precise amount of the friction ; for if the end be elevated one-twentieth of its length, then the friction is one-twentieth the weight of the horse and platform. Secondly, to determine the power, when the end is still further raised, measure the difference between the height,, thus given and the length of the platform. If, for in- stance, the height of the inclination is one-eighth of its length, and the horse is found to weigh eight hundred pounds, then the power is one hundred pounds, or one- eighth the weight of the horse. 190 MECHANICS. This rule will not, however, apply, when the drmight of the horse is added to its weight; for it usually happens that the weight alone is not suiEcient, without placing the platform in too steep a position for the horse to work comfortably. He is, therefore, attached to a whiflle-tree, and to ascertain the power requires the use of the dyna- mometer, in connection with tlie preceding mode. Great improvement has been made of late years in Fig. ai4. the appendages of thrashing machines. The large number of laborers formerly employed in raking and separating the ^-^P^SSS-^^W^W straw, and placing it "''^ on the stack, is now dispensed with, and the whole done by machinery, working by the same power Pitts' Thrasher and Straw Carrier. that drives tlie thrasher. Among the best and most widely known ma- chinery for this purpose is that invented by H. A. Pitts, and represented in a portable form by fig. 214. It sepa- rates the grain, clenns it, and carries the straw by means of the elevator, (shown folded in the cut,) to the top of the highest stack. The tread-powei is successfully applied to churning, as shown in the cut, (fig. 215.) The employment of a sheep, of one of the larger breeds, has been found better and more convenient than a dog, as it is heavier, more quiet, less averse to the labor, and when the task is done, it is turned into the yard or pasture, where it is readily found next time. The cost of horse-powers and thrashers combined, of the different forms, varies from §225 to $400. CORN SHELLERS. Fig. 215. 191 churn worked hij dog-power Corn Shellers are made for both hand and horse- power. One of the most convenient and compact hand machines is SurralFs, made of iron, furnished with a fly- rig. 216 wheel to equalize velocity, and worked by one person while another feeds it, one ear at a time. Or, one person ,alone will turn it with one hand, while the ears are drojjped in with the other. Several other good corn shellers are made mostly of wood. Fig. 217 represents a sheller, mostly of cast iron, driven by horses, by means of mn-aiFs Com SMier. the band partly seen in the cut. The corn in the ear is thrown into the hopper at one end, and is separated from 192 3m:echanics. the cob by rows of teeth revolving in a concave bed and Fig. S17. Kg. 218. Horse-jmver Com Shelter. set spirally, thus carrying the cobs along and ejecting them from the opposite end. For shelling corn in large quantities, powerful machines driven by horses or steam are required. An excellent sheller for this purpose is made by Richards, of Chicago. The coin is shoveled directly from the wagon or crib in- to the hopper, and requires no extra feeders, or hands, to keep the machine from choking. It is built wholly of iron, combining strength and dura- bility. The s"hellers are made of different sizes requiring from two to twelve horse- power. The former will shell one bushel, Eiclmrds- Corn Sh^Oer. and tlie latter ten bushels per minute. The cost varies from $175 to $475. The following is a description of the woi-king part. The shelling cylinder is made of heavy rods of wrought iron, placed equidistant, presenting a corrugated surface, which cannot wear smooth. "Within this, a revolving iron RICHARD'':} CORX SHEI.LEE. 193 cylinder, with ciiiiled teeth, thrashes the corn against the surfaces of tlie rod cyliniler. The teeth approach the rods sufficiently close to keep every ear in rapid motion, shelling one ear or one bushel with tlie same facility. A regulator at the discharge end places the machine within control of the operator. The spaces between the rods allow tlie shelled corn to escape freely, thus lessening the draught, relieving the cylinder from clogging and from all liability to cut or grind the grain. The cleaner consists of a cylindrical screen revolving around the whole length of the slieller, and extending be- yond it. A heavy fan blast passes directly through this screen, and under it, subjecting the corn to two separate cleanings, and delivering it in good condition for market. The cleaned corn discharges upon either side desired, and the cobs are delivered with the dust at the end of the ma- chine. AECHIMEDEA:]' r.00T>-\VASHEE. The spiral principle has bean successfully applied in the Archimedean lioot^oasher, (fig. 219.) The roots to be Pig. 219. CroskUVs Archimedean Root-washer. ■washed are first delivered into a hopper, from which they 9 194 MRiIlAXICS. Fig. 220. pnss into an inclined cylinder made of strips of wood with grate-like openings. The cylinder lias two portions sepa- rated by a partition, in the first of which they remain while the handle is turned for wasliing them. As soon as the washing is finished, the motion of the liandle is re- versed, which throws lliem into the other part, which has a spiral partition, along which they pass until they drop into a spout outside. EOOT SLICERS. Cutting roots for feeding animals reduces them to a better condition for eating, and by preventing chokinf;- renders them safer. Out hay and straw may be mixed with them and the whole fed together. The older machines merely sliced the roots with their broad, straight knives. The newer ones pare them off into narrow chips and break and soften them. For feeding sheep, the slices must be small. For this purpose, machines are now made by Belcher & Taylor, of Chicopee Falls, Mass., cutting slices three-fourths of an inch wide, and half an inch thick. They are mostly run by hand, but horse-power machines are furnished for large flocks. The knives are usually curved, and their form is shown in the annexed cut (fig. 320), which represents a machine made of iron, the cutting cone being taken out and exhibited below. At the present time, the frame and hopper of root-slicing machines are mostly made of wood. Wellington's Boot Gutter. VARIOUS KINDS OF PAE:M IflLLS. 195 FAKM MILLS. These are made of iron, and with burr-stones. The former are cheaper, and answer a good purpose for grind- ing feed for domestic animals. The latter may be also used for grinding flour. f Figure 222 represents an iron farm mill manufactured by R. H. Allen & Co., and others. The grinding sur- faces are of chilled iron, so arranged as to be self-shnrpening, and to last a long time without repairs. When necessary, new plates are readily inseited. The mill is driven by horse or other power, the band from which i-v3 seen in the cut. It will grind from five to ten bushels per hour, varying with the fineness of the meal and the amount of driving pow- er, ' Fig. S23. Eig. 223. AllerCa Horse Mill. A two-horse railway power may be used to advantage. This mill is about three feet square, four feet high, and weighs three hundred pounds. Several other iron mills of a similar chai-acter are made by different manufacturers, and usually cost about $50. Among the burr-stone farm mills, one of the best, most compact, and most substan- tial, is Foreman's, of Chicago, It will be perceived from this Forsinan^s MiU. represented by fig. 223. ]9G MECHANICS. figure that tlie spindle is horizont.'il, and tlic faco of the stones vertical. The frame is of iron. I'he diameters of the stones vary from sixteen to thirty Inches, and the weight from 400 to 1,500 lbs. The smaller size may be run with a power of one to four horses; the larger, witli that of ten to thirty horses. Prices 8150 to $375. The manufacturers cl:iim that it will grind from one and a half to three bushels per hour, for each horse-power used in driving it. (See page 390. ) THE COTTON GIN. Since the invention of the Cotton Gin by Eli Whitney, great improvements have been made, by which the cotton is cleaned with great rapidity and in a perfect manner. Fig. 284. Emery's Cotton Gin — Sectwn. The machine formerly made by H. L. Emery, of Albany, is one of the best for this purpose. It is represented in section in fig. 224. The hopper, fft the right, is furnished with what is termed a Picker Moll Svpporter, which re- volves within the hopper, in the direction shown by the arrow, and prevents the cotton from becoming packed. It EMERY S COTION GIN. 197 is then tnken by the teeth of the saw cylinder, which re- duce the cotton to a fine condition. These teeth are swept by the brush cyUnder, which, running in the same direction with the teeth, and slightly faster, carries the cotton oflf from them. Fig. 225 represents the opeiation, the seed escaping from the bottom of the hopper and the Fig. 225. ttiith Condenser. cotton thrown to the rear into the condenser, whicli fin- ishes the cleaning process and packs or condenses the lint cotton within a limited space. The arrows shown in the section indicate the direction of the revolutions of the ; picker, saws, and brush cylinder, and also the course which the cotton takes in passing through the gin and condenser. (See page 390.) PART II. MACHINERY IN CONNECTION WITH WATER. GENERAL PRINCIPLES. Hydrostatics * treats of the weight and pressure of liquids when not in motion ; HYDBA.D-Lios,f of liquids in motion, as, conducting water through pipes, raising it by pumps, etc.; and Hydrodynamics | includes both, by treating of the/orces of tlie liquids, whether at rest or in motion. CHAPTER I. HYDROSTATICS. UPWARD PRESSURE. A remarkable property of liquids is their pressure in all directions. If wc place a solid body, as a stone, in a vessel, its weight will only press upon the bottom ; but if we pour in water, the water will not only press upon the bottom, but against the sides. For, bore a hole in the side, and the side pressure will drive out the water in a stream ; or boi'e small holes in the sides and bottom of a tight wooden box, stopping them with plugs ; then press this box, empty, bottom downward, into water, allowing none to run in at the top. Now draw one of the side plugs, and the water will be immediately driven into the • From two Greek words, hudar, water, and statos, standing, or at rest, t From two Greek words, hudor, water, and aulas, a pipe. I From t wo Greuk words, hiidor, water, dunamis, power. 198 UPWARD PKESSUEK OF LIQUIDS. 199 box by the pressure outside. If a bottom plug be drawn, the water will immediately spout up into the box, show- ing the pressure upward ngainst the bottom. Hence the pressure in all directions, upward, sideways, and down- ward, is proved. The upward pressure of liquids may be shown by pour- ing into one end of a tube, bent in the shape of the letter U, enough water to partly fill it ; the upward pressure will drive the water up the other side until the two sides are level. On this principle depends the art of conveying water in pipes under ground, across valleys. The water will rise as high on the opposite side the valley as tlie spring which supplies it. The ancient Romans, who were unac- quainted with the manufacture of strong cast-iron pipes, conveyed water on lofty aqueducts of costly masonry, built level across the valleys. Even at the present day, it has been deemed safest to build level aqueducts for con- veying great bodies of water, as in very large pipes the pressure would be enormous, and might result in violent explosions. If the valleys are deep, the pipes must be correspond- ingly strong, because, the higher the head of water, the greater is the pressure. For the same reason,' dams and large cisterns should be strongest at bottom. Reservoirs made in the form of large tubs require the lower hoops to be many times stronger or more numerous than the upper MEASUEBMENT OP PBESSUEE AT DIFFERENT HEIGHTS. The amount of pressure which any given height of wa- ter exerts upon a surface below may be understood by the following simple calculation : If there be a tube one inch square (with a closed end), half a pound of water poured into it will fill it to a height 200 MACHIS^EKY IS COXXECTIO.V ■^^■1T:I WATER. H— - I I of fourteen inches;* one pound will fill it twenty-eight Pig. 226. inches ; two pounds, fifty-six inches ; ■albs. 56in. ten pounds, twenty-three feet; twenty pounds, forty-six feef, and so on. Kow, as the side pressure is the same as the pressure downward for the -i7?.ibs.4zin. same head of water, the same column will, of course, exert an equal pressure on a square inch of the side of the tube. Or, if the tube be bent, as lib 28111. shown in the annexed figure (fig. 226), the pressure upward on the end of the tube, at a, will be the same for the various heights. • 'A lb. 14 in. Now, as the pressure of a column fifty feet high is about twenty-two pounds on a square inch, the pressure on the ybur sides is equal to eighty- eight pounds for one inch in length. Hence the reason that considerable strength is required in tubes which much head of water, to prevent their being torn by its force. DETEEMINING THE STKEXGTH OP PIPES. The question may now arise, and it is a very important one, How thick must be a lead tube of this size to prevent danger of bursting with a head of fifty feet, or of any other height ? To answer it, let us turn to the table of the Btrengtli of Materials in a former part of this work, where we find that a bar of cast lead one-fourth of an inch square will bear a weight of fifty-five pounds. If the * This is nearly correct, for a cubic foot (or 1,728 cubic inches) of water weighs 63 lbs. Consequently, o;ie pnund will be 37.9 cubic inch- es, and will till the tube nearly 33 iuclies hi^h. CALCtTLATISTG THE STRENGTH OF TUBES. 201 tube he only one-sixteenth of an inch thick, one inch of one of its sides will possess nn equal strength, that is, will bear fifty-five pounds only, and the tube would conse- quently burst with fifty feet head. If one-tenth of an inch thick, the tube would just bear the pressure, and, to be safe, should be about twice as thick, or one-fifth of an inch. Half this thickness would be sufficient for twenty- five feet of water, .and would require to be doubled for one hundred feet. A round tube, one incli in diameter, having less surface to its sides, would be about one-third stronger. A tube twice the diameter would need twice the thickness; or if less in diameter, a proportionate de- crease in tliickncss might take place. If, instead of cast lead, milled lead were used, the tube would be nearly four times as strong, according to the table of the strength of materials already referred to. SPEIKGS A^O ARTESIAN WELLS result from the upward pressure of water. Rocks are usually arranged in inclined layers (fig. 227), and when Fig. 2S7. cL rain falls upon the sui-facc, as at e d, it sinks down in the more porous parts between these layers, to c. If the lay- ers happen to be broken in any place below, the water finds its way up through the crevices by the pressure of the head above, and forms springs. If there are no open- ings through the rocks, deep borings are sometimes made; 9* 202 MACHINERY IX CONNECTION' WITH WATEE. artificLilly, through which the writer is driven up to the surface, as at a, forming what are termed Artesian Wells. The head of water which supplies them may he many miles distant, the place of discharge being on a lower level. It has sometimes been found necessary to bore more than a thousand feet downward before obtaining water which will flow out freely at the surface of the earth. DETERMINING THE PEESSURE ON GITBX SURFACES, The pressure of liquids upon any given surface 73 always exactly in proportion to the height, no matter what the Fig. 328. Wl [ fc--H shape of the vessel may be. If, for instance, the vessel a (fig. 228), be one inch in diameter, and the vessel b be three inches in diameter, the water being equally high in both, the press- ure on the whole bottom of b will be nine times as great as on the bottom of a / or any one inch of the bottom of b will receive as great a jiressure as the bottom of a. Again, if the vessel c, broad at the top, be narrowed to only an inch in diameter at bottom, the press- ure upon that inch will still be the same, most of the weight of its con- tents resting against the sides, d d. If the vessel, A (fig. 229), be filled with water to a height of fourteen inches, the pressure will be half a pound on every square inch of the bottom, or upon every square inch of the sides fourteen inches below the sui-face. If the tube, C, be an inch square, the water will be driven into it with a force of half a pound, and will press with that force against the one-inch surface of the stop-cock, C. If A PUZZLE EXPLAINED. 203 the tube, B, be now filled to an equal height, the same force will be exerted against the other side. To prove this, let the stop-CQck be opened, when the two columns of water will lemain at an exact level. If enough water be now poured into the tube, B, to fill it to the top, it will immediately settle down on a level with the water in A, raising the whole surface in the lat- ter. This result has seemed strange to many, who can not conceive how a small column of water can be made to balance a large one, and it has been therefore termed the Hydrostatic Paradox. But the difiiculty entirely vanish- es, and ceases to appear a paradox, when we remember that the water in the larger vessel rises as much moro slpwly than it descends in the smaller, as the large onu exceeds the smaller ; thus acting on the principle of vir- tual velocities in precisely the same manner that a hea\y weight on the short end of a lever is upheld by a small weight on the long end. The great mass of water is sup- ported directly by the bottom of A, in the same way tliat nearly all the weight on the lover is supported by the fulcrum. A man who was seeking a solu- tion to the absurd mechanical problem of perpetual motion, and who supposed that the large mass in A would overbalance the small column in B, .nnd drive it upward, constructed a vessel in the form shown in fig. 230, so that the small column, when forced upward, would flow back into the larger vessel perpetually. He was, how- Attempted PcTpetual ° ,-^^.,"' ,„.-,. Motion. ever, greatly surprised to see the fluid m both divisions settle at the same level. This principle may bo further explained by the following experiment :. A B (fig.231) represents the inside of a metallic vessel, with a bottom, C, which slides up and down, water- tight. If water be poured in to fill the lower or larger part only, it will be found to press on the sliding bottom Fig. 230. 204 MiCHIXEEY IX CONNECTION WITH WATEK. with a force exactly equal to ita own weight ; that is, if there is a pound of water, it will press on the bottom with a force equal to one pound. Now, if the bottom be pushed rig. 231. upward, so as to drive the water into the narrow part of the vessel, the pressure upon the bottom becomes instantly much greater, or equal to many pounds, the water being the same in quantity, but with a much higher head than before. Suppose the nar- row part of the vessel is twenty times smaller than the larger part, then, in pushing the bottom up one inch, the water is driven twenty inches upward in the tube. So then, according to the rule of virtual ^•Glo(,•ities, it will require twenty times the force, because it moves U])warcl twenty times faster.* This, then, is precisely similar to the in- stance where a pound on the longer end of a steelyard balances twenty pounds on the shorter pj^. 332 end. In this instance, the upper parts, ^^45 D D, of the vessel operate as the fulcrum of a lever, and offer resistance to the slid- ing part as soon as the «ater begins to ascend the tube. HYDEOSTATTC BELLOWS. This principle is shown in the Hy- drostatic Bellows (fig. 232), which con- ^^^§ sistS of two round pieces of board, Hydrostatic Bellowt. connected by a narrow strip of strong leather; into it is inserted a long, narrow tube, B, with a small ftinnel, e, at the top. When water is poured into this tube, it will raise a weight as much greater than the weight of the * The pressare will be as great npou the bottom aa if the vessel con- tinued a uniform size all the n ay up. HTDKOSTATIO PEESS. 205 water in the tube as the surface of tlie upper board ex- ceeds the cross-section of the tube. Thus, if a pound of water fills a tube half an inch in diameter, and the bellows are two feet in diameter, then this pound will raise more than two thousand pounds on the bellows (if it be strong enough), because the surface of the bellows is more than two thousand times greater. In the same way, a strong, iron-bound hogshead may be burst with the weight of a single gallon of water by pouring it into a long and narrow tube set upright in the bung of the filled hogshead. If, for instance, the inner surface of the hogshead be 20 square feet, or 2,880 square inches, a tube of water 23 feet high will press with a force of 10 pounds on every square incli, or equal to a force of 28,800 pounds, or 14 tons, on the whole surface. HYDKOSTATIC PEESS. The Hydrostatic Press owes its extraordinary power to a similar principle ; but, instead of a bellows, there is a moving piston in a strong metallic cylinder; and instead of being worked by the mere weight of the water, it i? driven into the cylinder by means of the lever of a pow- erful forcing-pump. An instrument of this sort, possess- ing enormous power, was used to elevate the great tubula' iron bridge in England. It was found necessary to make the sides of the cylinder into which the water was driven no less than eleven inches thick, of soUd iron ; and so great was the pressure given to the confined water, aa to have forced it up through a tube higher than the summit of Mont Blanc. In the port of New York, ves- sels of a thousand tons' burden have been lifted by the hydrostatic press. This machine has been applied in compressing hay, cot- ton, and other bulky substances into a compact form, so tliat they may occupy but little space, for conveyance to 206 MACIimERY IN CONNECTION TY'ITH WATER. distant markets. The following figure (fig. 233) exhibits the difierent parts of this powerful machine. A is a cis- tern to supply water, which is raised by working the han- dle, B, of the forcing-pump; the water passes through the valve, C, opening upward, and through the spring valve, Hydrostatic Press. D, opening toward the large cylinder, E. Being thus driven into the space, E, it raises the piston, F, and exerts a prodigious pressure upon the mass of hay or cotton, G. The piston is lowered by turning the screw, H, which al- lows the water to pass back into the cistern at I. In the figure the hay or cotton is shown as visible to the sight, in order to represent the whole more plainly ; but in prac- tice it is thrown into a square box or chamber of strong plank, of the size of the intended bundle. One side ia HYDROSTATIC PBESS. 207 hung upon stout hinges, and is opened for the removal of the bale when the pressing is completed. To estimate the power of this machine, divide the square of the diameter of the piston, F, by the square of the diameter of the piston of the forcing-pump, and multi- ply the quotient by the power of the lever, B. For ex- ample, suppose the piston,*^ F, is 16 inches in diameter, and the piston of the forcing-pump is 2 inches in diameter. The square of 16 is 256; divide this by 4, the square of 2, and the result will be 64. If the lever, B, increases the power five times, the whole power of the macliine will be 320 ; that is, a force of one pound applied to the lever will raise the large piston with a force equal to 320 pounds ; or, if a force of 100 pounds be given to the lever, the power will be 33,000 pounds, or 16 tons. Reducing the diameter of the smaller piston to half an inch, and in- creasing the foi'ce of the lever to twenty times, the whole power exerted will be thirty-two times as great, or equal to 960 tons. In ordinary practice, it is more convenient and economical to reduce the diameter of the larger piston to a few inches only, making the forcing-pump correspond- ingly small, the power depending entirely on the dispro- portion between tliem. Such presses may be worked rap- idly by horse, water, or steam power. One great advantage which the hydrostatic press pos- sesses over those worked by screws results from the little friction among liquids, nearly the only friction existing in the whole machine being that of the two pistons, which is comparatively small. Another is the smallness of the compass within wliich the whole is comprised ; ' for a man might, with one not larger than a tea-pot, standing before him on a table, cut through a thick bar of iron with as much ease as he could chip pasteboard with a pair of shears. 208 MACniNEEY IX CONNECriON WITH WATER. SPECIFIC GRAVITIES. Fig. am. In connection with Hydrostatics, the subject of the specific gravities of bodies is one of importance. The specific gravity of a substance is its comparative weight with some other substance, an equal bulk. of each being taken. Water is usually the standard for comparison. To ascertain the specific gravity, weigh the body both in and out of water, and observe the difference ; then divide the whole weight by this difference, and the quotient will be the specific gravity sought. For example, if a stone weighs 12 lbs. out of water and 7 lbs. in water, divide 12 by 5, and the quotient is 2.4, which shows that the stone is 2*|,„ times heavier than water. Figure 234 shows the mode of weighing the body in water, by suspending it be- neath a balance on a hair or thread. It was in a similar way that Archimedes is said to have succeeded in detecting the suspected fraud in the manu- facture of the golden crown of the ancient king of Syra- cuse. He first weighed it, and then found that it die placed more water when plunged in a vessel just filled than a piece of pure gold, and also that it displaced less than silver, whence he inferred the mixture of these two metals. When the specific gravity of a substance lighter than water is to be ascertained, it is loaded down by a weight, so as to sink in water, for which allowance is made in the calculation. A very simple way to determine this in dif- ferent kinds of wood, is to form them into rods or sticks of uniform size throughout, and then to observe what portion of them sink when placed endwise in water. Instrument for taking Specific Giavtties. TABLE OP SPECIFIC GRAVITIES. 209 A knowledge of the specific gravities of various sub- stances becomes useful in many ways, among which is ascertaining the weight of any structure, machine, or im- plement, by knowing that of the material used in its man- ufacture; determining the cost, by the pound, of puch material ; or knowing the bulk or size of any load for a team. The latter may often be of great use in ordinary practice, by enabling the teamster to calculate beforehand the amount of load to give his horses, whether in timber, plank, brick, lime, sand, or iron, without first subjecting them to overstraining exertions in consequence of error in random guessing. Tables of specific gravities, for this purpose, and weights of a cubic foot of difierent substances, arc here given. TABLE OF SPECIFIC OKAVITIES. Gold, pure 19.36 " standard 17.16 Mercury 13.58 Lead 11.35 Silver. 10.50 Cupper 8.83 Metals. Iron 7.78 " cast 7.20 Steel 7.82 Brass, common 7.83 Tin 7.39 Zinc 6.86 Stones and JEJarths. Brick 1.90 Chalk 3.35 to 3.66 Cliiy 1.93 Coal, iintliracite, about 1.53 Coal, bituminous 1.37 Charcoal 44 Earth, loose, about 1.50 Flint 3.58 Granite, about 3.65 Gypsum. 1.87 to 3.17 Limestone 3.38 to 3.17 Lime, quick 80 Marble 3 56 to 3.69 Peat 60 to 1.S3 Salt, common 2.13 Sand 1.80 Slate 2.67 Woodif—dry, Green wood often loses one-third of its weight by seasoning, and •ometimcg more. The game kind varies in compactness with soil, growth, exposure, and ago of the trees. 210 MACniXEKT IN CONNECTION WITH WATEE. Apple 68 to .79 Aeh, white 73 to .84 Beech 73 to .85 Box 91 to 1.33 Cherry 71 Cork 24 Elm 58 to .67 Hickory 84 to 1.00 Maple 65 to .75 Pine, white 47 to .56 Pine, yellow 55 to 60 Oak, Ensrlish 93 to 1.17 " white 85 '■ live 94tol.l3 Pophir, Lombardy 40 Pear 66 ^ Plum 78 Sassafras 48 Walnut 67 Willow 58 Miscellaneous. Beeswax 96 Butter 94 Honey 1.45 Lard. 94 Milk 1.03 Oil, linseed 94 Oil, whale 98 " turpentine 87 Sea wiiter 1.03 Suffir. 1.60 T.iUow 93 Vine'rar. 1.01 to 1.08 Weights of n. Cubic Foot of vanous Snb^tavces^ frirni which the Bulk of a Load of otie Ton may be easily calculated. Cast lion 4.50 pounds Water 63 " White pine, seasoned, about 30 " Wliiteoalc, " " 53 " Loose earth, about 95 " Common soil, compact, al)out 124 ** Clay, about 135 " Clay with stones, about 160 " Brick, about 135 " Bulk of a Ton of different Substances. 23 cubic feet of sand, 18 cubic feet of earth, or 17 cubic feet of clny, make a ton. 18 cubic feet of gravel or earth before diguing make 27 cubic feet when dug; or the bulk is increased as three to two. Thcre- foie, in fillinur a drain two feet deep above the tile or stones, tlie earth Bhould be heaped up a foot above the surface, to settle even with it, when the earth is slioveled loosely in. A cubic foot of solid half-rottedl manure weiulis about 56 lbs., requiring about 36 cubic feet to the ton. If coarse or dry, more will be required. Hay varies much in specific grav- ity with the kind, and tlie de^'ree of prc.-. Common Pump ; 6, lower or fixed valve , G, -piston with valoe^ a, opening upward; D (i, piston- rod } F, spout. has been inade in the common pump for farms within a few years. The best cast-iron pumps, made almost wholly of this metal, ex- ceed in durability and ease of working those formerly con- structed of wood, and e.vcel others in cheapness. Fig. 242 exhibits the working of the common pump, the water first passing through tho fixed valve below, and then through the one in the piston ; both opening upward, it cannot flow back without instantly shut- ting them. The water is driven up by the pressure of the at- mosphere, explained in the next chapter. Fig. 243 is an iron cistern pump, showing the mode of bolting it to the floor or platform, and rep- resenting, also, its neat and com- pact form, occupying but little space at one side, or in the corner of a kitchen, over the cistern. PUMPS. 219 Fig. 244 represents a cistern or well pump, so constructed that the wbrking parts are about 20 inches below the plat- form, or base of the pump, and it is therefore well adapt- ed for outdoor work. If the well or cistern is kept covered tight, the pump will not freeze below the platform. It will succeed in any well not ovelr twenty feet deep, and by means of its various couplings may be made to draw water in a horizontal or in- clined position, provided the whole height is not much over twenty feet. Fig. 343. Cietem Pump. Non-freezirtg Pump. An excellent deep-well pump, for wells of thirty feet depth or more, is represented by fig. 245 ; the working part, being placed at the bottom of the well, is adapted to any depth of water, the rod working safely Within the pipe. The lower part of the cylinder is fur- nished with a strainer, and is plugged at the bottom, to 2.20 MACHIXKHY I-V CONNECTION WITH MATKIl. Fife'. 346. F'g- 245. Drive Pump. prevent the ingress of sand and mud. The connecting pipe between the cylinder at the boltom and the standard at the top is wi ought oi galvanized iron. The pump, of course, needs bracing, to pie\ent swinging when worked. Drive Pumps. — ^Fig 246 rep resents the new modp of makinj; wells, by simply driving into the earth common iron gas-pipe, pointed at the lower end, and perfoiated at the sides, near the lower extremity. \ll> Deep well Pumji DRIVE PUMPS. 221 for the ingress of water— thus' obviating entirely the cost and labor of digging wells. If driven through a subter- ranean spring, a stratum of water, or a wet layer of sand or gravel, it is obvious that the water will immediately flow through the perforations into the pipe ; and, by attaching a good pump to the pipe and pumping for a time, all the par- ticles of sand and fine gravel will be drawn out ; and the cavity thus formed around the perforation s will remain filled with pure water. These tubes and pumps are admirably adapted to localities where large beds of wet gravel exist fifteen or twenty-five feet below ; and, in fact, to all soils where large stones nre not abundant. Where these occur, the pipe must be witiidrawn, and tried in a new placBj until success is attained. In the Chain I\imp, a partial cross-section of which is Fig. 347. Fig. 848. Clmin Fump. Section. ■ Bolary Pump, for Barrels, etc. here shown, (fig. 247), the chain is made to revolve rapid- ly on the angular wheel by means of a winch attached to 222 MACHINERY IN COMTECnON WITU WATEE. Fig. 249. the upper one, and being furnished with a regular Bucces- sion of metallic discs, which nearly fit the bore in the tube, rt, the water is carried up in large quantities. When the motion is discontinued, tho; water settles down again into the well, and consequently this pump is not liable to accident by freezing. By sweeping rapidly through the water, it preserves it in better condition, and prevents stag- nation. The friction being very small, it will last a long time without wearing out. Motary Pumps. — A succes- sion of cavities made in the exterior of a short cylinder receive the water from the pump-tube below, and force it away into the elevating tube. When driven fast, it pumps with great rapidity.* It possesses this advantage over the common pump, that the ra.otion being continuous, no force is lost by repeatedly checking the momentum. In the figure on the preceding page, the pump is represented as inserted in a barrel of oil, which is to be emptied into the reservoir above, and is Suction and Fonang-pump. worked by hnnd. Larger rotary pumps :irc driven by horse and steam power. TURBINE WATEK-WHEELS. 223 Suction and Forcing-Pump. — The accompanying cut (fig. 249) represents a suction and forcing-pump combined in one, for the purpose of drawing water from a well or cistern, and forcing it to tanks in upper stories, or throwing water into upper rooms in case of fire. By lengthening the rod, the working parts may be placed at the bottom of a deep well, and the whole used as a deep well pump. TUKBINB WATER-WHEELS. The large wooden wheels formerly used for the appli- cation of water power to mills and other machinery are rapidly giving place to iron Turbine wheels. Overshot wheels, the best kind formerly employed, were turned by the weight of the water, the whole of which was held in the slowly descending buckets of the wheel. Turbine wheels do not hold the water, but merely receive and im- part the force of the rushing current, the water being held by the flume above. Hence, a turbine wheel of quite small size may impart to machinery nearly the whole force of a powerful current of water. Turbine wheels are placed in a horizontal position, witn ^'s- 2S0. vertical axes. Being under water, they never freeze ; and they are not impeded by back-water when a flood occurs. There are two principal kinds among those in common use, — those, like the Reynolds wlieel, which have a single opening at the side, through which the wa- ter is p,dmitted ; and such as the Leffel and Van de Water wheels, into which the water is admitted through several openings around them. Section of Reym/di 224 MACHINEEY IN CONNECTION WITH WATER. Fig. 252. Tlew of JteifnolSs' Turbbie -!B ^flleel. Fig. 250 is a section of the Reynolds wheel; G, the gate for admitting the water through the hori- zontal shute from the flume ; A, A, the circu- lar pnssnge for the water, which is gradually di- minished in volume as it strikes tlie buckets or blades, Ji,B, and escapes through the bottom and top of the wheel. The arrows sliow the currents, and the cui-ved dotted lines the openings through which the water escnpes — the curved arrows exhibiting the re- bounding of the current against the blades, before passing out through the is- sues. Fig. 251 is an exterior ■view of the wheel, showing the g.ite for the admission of the water ; and iig. 252 represents the shaft and Fig. 354. i Sectirm of Van de Watfr Wked. buckets separate. Fig. 253 is a section of the Van de Water wheel, G, G, G, G, being the gates for admitting wa- ter, and H, JB, the buck- ets — the arrows rep- resenting the entering currents. Jl shows, by dotted lines, the position Van de Water Vfhed. of One of the gates when The water, after entering the buckets, passes out closed. TUBBINE WATEK-TVHEEtS. 225 below, where the blades are curved backwards, to reeeiA'o all the force of the estiapiitg water. Fig._254 is a view of this wheel, showing the admission gates, and the whetl at the top, for opening and shutting the gates at one movement. Tiie Reynolds wheel is placed under water, outside the flume, and the current admitted at the side, as already stated. The Van de Wa.ter wheel is placed within, and on the bottom of the flume, in the floor of which a circu- : lar hole is cut, through which the water escapes. James LefEel & Co., of Springfield, Ohio, are extensive manu- facturers of excellent turbine wheels, of which there are now over 7,000 in successful operation in driving flour- ing mills, saw-mills, and various other machinery. Turbine wheels, of the best construction, do not lose more than onerseventh or one-eighth of the whole descend- ing force of the Water. Hence, the power of any stream may be determined beforuhand with much accuracy, if the descent or head and the number of cubic feet of wa- ter per minute are known. It has been already shown in this work, that a single horse-power is equal to lifting 33,000 lbs. one fbot, i)er minute. This is equivalent to raising 530' cubic feet of water to the same height, or 53 cubic feet, ten feet high. A stream, then,- which falls 10 feet, and discharges 53 cubic feet in a minute, or nearly 1 per second, has an inherent force of one horse-power. Add one-seventh, making it about 63 cubic feet, and we have the size of a stream for one horse-power, at ten feet ,fall.. Twenty feet descent would double the power, forty, quadruple it, and so oil ; and a similar increase result from employing a larger stream. As examples, a small' wheel, seven or eight inclies in diameter, will be sufficient for such a purpose. One of this size, with 20 feet head, and discharging 70 or 80 cubic feet of water per minute, will possess about three horse-power ; and with forty feet head, requiring over 100 cubic feet per minute, it will have a power of eight or nine horses. in* 226 MACeiNEET UT COIWECTIOK "WITH WATER The simple rule given in the second paragraph of the present chapter, for determining the velocity of a current of water spouting out under any given head, will enable any one who undei'stands arithmetic to calculate the proper speed of a turbine wheel, wliiuh varies with the head and the diameter of the wheel. It is found that the buckets or blades should move with about two-thirds the ve- locity of the currunt as it rushes from tlie flume; hence, as an example, under a head of 16 feet, which drives out a stream about 22 feet per second, the exterior of the turbine wheel sliould move about 14 or 15 feet per second. If 1 foot in diameter, it should tiierefore revolve five times per second ; or, if 2^ feet in diameter, only twice per second. Otiier examples may be readily computed. There are occasional opportunities for employing water power for driving farm macliini-ry — as thrashing ma- chines, mills for grinding feed, corn shelters, wood saws, straw cutters, etc., by bringing streams along hill-sides,, or over blufis; in which cases, turbine wheels would be cheaper than steam-engines, and require neither food nor fuel. The waterof small streams might besaved in dams or ponds, giving a power of five or six horses for one clay in each week for grinding, thrashing, and other purposes. THE WATKE-EAM. One of the most ingenious and useful machines for ele- vating water is the Water-ram. It might be employed with great advantage on many farms, were its principle and mode of action more generally understood. By means of a small stream, with only a few feet fall, a current of water may be driven to an elevation of 50 feet or more above, and conveyed on a higher level to pasture-fields for irrigation, to cattle-yards for supplying drink to domestic animals, or to the kitchens of dwellings for cu- linary purposes. THE WATER- BAM. 227 Its power depends on the momentum of the stream. Its principal parts are the reservoir, or air-chamber, A, (fig. 255), the supply pipe, jB, and the discharge pipe, C. The running stream rushes down the drive, or supply- pipe, J3, and, striking tlje waste valve, D, closes it. The stream being thus suddenly checked, its momentum opens the valve, ^, upward, and drives the water into the reser- voir, A, until the air within, being compressed into a smaller space by its elasticity, bears down upon the water, and again closes the valve, JE. Th^ water in the supply- pipe, £, has, by this Fig. 255. time, expended its mo- N mentum, and stopped I «v running; therefore the ^1/ A valve, J), drops open I .^__/ again, and pei-mits it to il ^M^/ escape. It rec&mmences \^-x.^^ ^^vj ^ ( Jfs, running, ^mtil its force ^'"''C' ^ n _^ ■ s?^ •^ J.T again closes the waste ^ ~ — -w^-^ valve, -D, and a second Water-ram. portion of water is driven into the reservoir as be- fore, and so it repeatedly continues. The great force of the compressed air in the reservoir drives the water up the discharge-pipe, C, to any required height or distance. The mere weight of the water will only cause it to rise as high as the fountain head ; but like the momentum of a hammer, which drives a nail into a solid beam, which a hundred pounds would not do by pressure, the striking force of the stream ererts great power. The discharge pipe, G, is usually half an inch in cfiame- ter, and the supply-pipe should not be less than an inch and a fourth. A fall of three or four feet in the stream, with not less than half a gallon of water per minute, with a supply-pipe forty feet long, will elevate water to a height as great as the strength of common half-inch lead 228 MACHINERY IN CONNECTION WITH WATER. pipe will bear.* The greater the height, in proportion to tlie fall of the stream, tlie less will be the quantity of wa* ter elevated, as compared with the quanlity flowing in the stre.-im, or escaping from the waste valve. H. L. Emery gives the following rule for determining the quantity of water elevated from a stream : — Divide the elevation to be overcome by the fall in the drive-pipe, and the quotient will be the proportion of water, (passing through the drive-pipe), which will be raised, — deducting, also, for waste of power and friction, say one-fourth the amount. Thus, with 10 feet fall, and 100 feet elevation, one-tenth of the water would be raised if tiiere were no friction or loss ; but, deducting, say one-fourth for these, seven and a half gallons in each hundred gallons would be raised, the rest escaping,' or being required to accomplish this result. Or, if the fall of the water in the supply-pipe be 3 feet, and the elevation required in the discharge-pipe be 15 feet, about one-seventh part of all the water will be elevated to this heiglit of 15 feet. But if the desired height be 30 feet, then only about one-four- teenth part of the water will be raised ; and so on in about the same ratio for different heights. A gallon per minute from the spring would elevate six barrels live times as high as the fall, in twenty-four hours, and at the same rate for larger streams. With a head of 8 or 10 feet, water may be driven up to a height of 100, or even 150 feet, provided the machine and pipes are strong enough. The best result is obtained when the length of the drive-pipe and the momentum it produces are just siif fieient to overcome the reaction caused by the closing of * When wiitei' is raised to a considerable elevation by means of the ■water-ram, the reservoir must possess great strength. If the beiglit be 100 feet, tlie pressure, as shown on a foimer pai^e, is about foity-four poiinds to the square inch. With an internal surface, therefore, of only 2 square feet, the force exerted by the column of water, tending to burst the reservoir, would be equal to more than twelve thousarj pounds. THE WATER-EAM. 229 the waste valve at each pulsation, and prevent the current of water from being thrown backward or up the drive- pipe ; hence, the greater the disproportion between the fall and the required elevation, the longer or larger must be the drive-pipe, in order to obtain sufBcient momentum. A descent of only a foot or two is sufficient to raise water to moderate elevations, but the drive-pipe should be of large bore. This pipe should always be very nearly straight, so that the water, by having a free course, may acquire suiRcient momentum to compress the air in the ram, and push the water up the discliarge-pipo. Water may be carried to a distance of a hundred rods or mi»re, but as there is some friction in so long a discharge-pipe, a greater force is required than for short distances. Tlie discliarge-pipe should, therefore, be larger, as the length is increased. Half an inch diameter is a common size, but long pipes may be five-eighths or three-fourths ; and, when practicable, it is more economical to reach an eleva- tion with a short and str.ong pipe, and to use a lighter and weaker one for the upper part. A pit, lined \\ith brick or smooth stone, for placing the ram, protects it from freezing ; and both pipos should be under ground for the same reason. The sui)ply or drive-pipe is usually 40 to 50 feet long ; but where the fall is 8 or 10 feet, it should be sixty or seventy feet. Unlike a pump, there is no friction or rubbing of parts in the water-ram, and, with clean water, it will act for , years without repairs, continuing through day and night its constant and regular pulsations, unaltered and unob- served. A small quantity of sand, or of dead grass or other fibre, in the water, will be liable to obstruct the valves, and render frequent attention necessary. ■WATER-ENGINES, including those for extinguishing fires and for irrigating gardens, are constructed on a principle quite similar to 230 MACUINEBY IJ( CONNECTION WITH W/.XJiK. Fig. 230. Fig. 257. Oarden-erujine. that of the vater-vam. In- stead, tiowevor, of comprcsc- ing the air, as in the ram, by the successive "strokes of a column of running water, it is accomplished by means of a forcing-pump, driving the wnter into the reservoir, from which it is again ex- pelled with great power, by means of the elasticity of the compressed air. Fig. 256 represents a garden-engine, movable on wheels, which may be used for watering gardens, washing windows, or as a small fire-engine. Fig. 257 is another, of smaller size, for the same purposes, ^^ and in a neat and compact C-jUndmal Gardm-tngine. form, the working part being within the cylindrical case. THE FLASH-WMEHI., FOK HAISINU WATEB. 281 THE FLASH-WHEEI, is employed with great advantage where the quantity of water is large, and is to be raised to a small height, as in draining marshes and swamps. It is like an undershot wheel with its motion reversed; in fig. 258 the ar- rows show the direction of the current when driven \ip- ward. It must, of course, be made to fit the channel closely, without touching and causing friction. In its best form, its paddles incline backward, so as to be nearly up- Pig. 258. Flask or fen wheel fjT raisir^s water rapidly short distar^ces. right at the time the water is discharged from them into the upper channel. It has been much used in Holland, where it is driven by wind-mills, for draining the surface- water off from embanked meadows. In Engl.ind, it has > been -driven by steam-engines ; and in one instance, an eighty-horse-power engine, with ten bnshels of coal, raised 9j840 tons of water six feet and seven inches high, in an hour. This is equal to more than 29,000 lbs. raised one foot per minute by each horse-power, showing that very little force is lost by friction in the use of the flash-wheel. 232 MACHINERY IN CONNECTION WITH WATEE. WAVES. NATURE OF WAVES. An inverted syphon, or bent tube, like that shown in fig. 259, may be used to exhibit the principle on which depends the motion of the waves of the sea. The action of the waves on shores and banks, and the inroads which they make upon farms situated on the borders of lakes and large rivers, present an interesting sub- ject of inquiry. If the bent tube (fig. 259) be ncnrly filled with water, and the surface be driven down in one arm by blowing suddenly into it, the liquid will rise in the other arm. The increased weight or head of tiiis raised column will cause it to f dl again, its momentum carrying it down belov/ a level, and driving the water up the other arm. The surfaces will, therefore, continue to vibrate until the forcu is spent. The rising and falling of waves depend on a similar action. The wind, by blowing strongly on a por- tion of the water of the lake or sea, causes a depression, and produces a corresponding rise on the adjacent surface. The raised portion then falls by its weight, with the add- ed force of the wind upon it, until the vibrations increase into large waves. THE WATER NOT PROGRESSIVE. \ Tiie waves thus produced have a progressive motion (for reasons to be presently shown), as every one lias ob- served. A curious optical deception attending this ad- vancing motion has induced many to believe that the water itself is rolling onward ; but this is not the fact. The boat which floats upon the waves is not carried for- ward with tiiem ; they pass underneath, now lifting it on WATEB OP WAVES NOT PHOGRESSIVE. 233 their summits, and now dropping it into the hollows between. The same eiFeet may be observed with the wa- ter-fowl, which sits npon the surface. It often happens, indeed, that the waves on a river roll in an opposite di- rection to the current itself. If a cloth be laid over a number of parallel rollers, so far apart as to allow the cloth to fall between them, and a progressive motion be then given to them, the cloth remain- ing stationary, a good representation of waves will bo afforded, and the cloth will appear to advance ; or if a strip of cloth be laid on a floor, repeated jerks at one end will produce a similar illusion. It is only the form of the wave, and not the water which composes it, which, has the onward motion. Let the dark line in fig. 260 represent the surface of the water. Fig. 200. A B A is tlie crest of one of the waves, and being higher than the surface at -B, it has a tendency to fall, and J? to rise. But the momentum thus acquired carries tlie>:e points so far that they interchange levels. Tlie same change takes place with the other waves, and the dotted line shows the newly formed surface as the water thus sinks in one place and rises in another. The same process is again repeat- ed, and each wave thus advances further on, and its pro- gressive motion is continually kept up. BEEADTH AND VELOCITY OF WAVES. Each wave contains at any one moment particles in all possible stages of their oscillation ; some rising, and some falling ; some at the top, and some at the bottom ; and the distance from any row of particles to the next row that is in precisely the same Stage of oscillation is called 234 MACHINERY IN CONNECTION WITH WATER. breadth of the wave, that is, the distance from crest to crest, or from hollow to hollow. There is a striking similarity between the rising and falling of waves and the vibrations of a pendulum, and it is a very interesting and remarkable fact, that a wave al- ways travels its own breadth in precisely the same time* that a pendulum, whose length is equal to that breadth, performs one vibration. Thus, a pendulum 39^ inches long beats once in each second, and a wave whose breadth is 39J inches travels that breadth in one second. The length of a pendulum must be increased as the square of the time for its vibrations ; that is, to beat but once in two seconds, it must be four times as long as for one second ; to beat once in three seconds, it must be nine times as long, and so on. In the same way, waves which travel their breadth in two seconds are four times as wide as those traveling their breadth in one second ; and thus their breadth, and consequently their speed, increases as the square of the time. Large waves, thei'efore, roll on- ward with far greater velocity than small ones. If only thirty-nine inches wide, they move about two an-M'lLL FOR rtJMPIKG WATEE. 243. by fig. 268, where A is the circnlaf wind-mill, with a number (if sails set obliquely to the direction of the ^ind, and al- ways kept facing it by means of the vane, B. The crank of the wind-mHl, during its revolutions, works the pump-rod, I, and raises the water from the well betieath. In whatever di- irii.26!). Barn mrmomtted with vAnt-millfar pumping water, ciitting itrifu), J/o. rection the wind may blovv, the ptirap wi'.l continue work- ing. The pump-rod, to ^ork steadily, must be immediately r.nder the iroii rod on wliich the rane turns. If the di- ft,ineter of the Avind-mill is four feet, it will set the pump ill motion even with a light breeze, and vith a brisk wind .will perform the labor of a man. Such a machine will pump the water ne'eded by .a herd of cattle, and it may be placed on the top of a barn, with a covering, to which may je given the architectural effect of a tower or cupola, as shown in fig. 269. A more compact machine, biit of more complex con- struction, is shown in fig, 370, where the upper circle moves aronnd with the wheel and vane on the fixed lower circle, to which it is strongly secured so as to admit of turning freely. In other respects it is similar to the pre- ceding. H* 250 MACHINEKY IN CONNECTION WITH AIR. Fig. 270. Wind-mills, like the preceding, which have fixed sails, shotdd not be more than three or four feet in diameter, and even then will require care in storms. If larger, they will become broken by severe winds. The remedy is either to move the sails by hand at every considerable change in the force of the current, which would require nearly constant attention ; or to use the self-regulating ma- chines, of which there have been several invented, some ■ of which have proved useful and durable. HalUday''s wind-mill has been much used for several years, and is made of various sizes, tlie larger possessing the power of several horses. It is self-regulated, in the following manner : When the mill begins to run too fast, it pumps water rapidly into a chamber or cylinder, and this increase of water moves an arm which turns the fans EKOWN S ■VVIND-MILL. 251 edgewise to the wind. When the wind slackens, a re- verse moTement takes place. Brown'' 8 wind-mill, made by the Empire Wind-mill Com- pany, of Syracuse, is a more recent invention, and has proved very successfnl. The annexed figure (fig. 271), rep- 3?i2. 271. BrawrCs (or Emixre) Wind^mill. resents one of the smaller sizes, adapted to farm purposes and pumping water for cattle. It is regulated in part by the centrifugal force of weights, and partly by the direct pressure of the wind. This regulating contrivance ren- ders the mill safe, even in a gale of wind. The larger 252 MACHINEET IN COIWECTION WITH AIE. sizes, which are fifty feet or more in diameter, poesesa much power, and are used for grinding grain, and other purposes. (See page 289. ) The work which a wind-mill is capable of doing de- pends very much on the site. If placed where the wind lias a long, uniform, and ste:».ly sweep, it will accomplish much more, and to better satisfaction, than if among hills or other obstructions, where the blasts are uncertain and changing. Wind-mills of large size are peculiarly adapted to pump- ing water into reservoirs, or from mines or quarries, where a few days of calm weather will not result in inconven- ience ; but they are not suited to manufactories where a constant power is required to furnish employment to men, but can be used for woi'k which may be intermitted or changed. Brown's wind-mill is sold at $75 dollars for the smal' size, with increase of prices up to |1,200 for large ones. CAtrSES OF WIND. The motion of air, in producing wind, is explained by the action of heat, although there are many irregular cur- rents whose cause is not well understood. The simplest illustration of the effect of heat in causing currents is fur- nished by the land and sea-breezes in warm latitudes. The rays of the sun during the day heat the surface of the land, and tlie air in contact with it, also becoming lieated, and thus rendered lighter, flows upward ; the ait from the sea rushes in to fill the vacancy, and causes the sea-breeze. During the night, the radiation of heat from the land into the clear sky above cools the surface to a lower temperature . than that of the sea ; consequently, the air in contact with the sea becomes heated the most, and rising, causes the wind from the land to flow in and supply the place. Trade-winds ave caused in a simila' CHIMNBT CUKEENT8. 253 way, but on a much larger scale, by the greater heat of tne earth at the equator, which produces currents from colder latitudes. These currents assume a westerly tend- ency, in consequence of the velocity of the earth being the greatest at the equator, and which, outstripping the momentum which the winds have acquired in other laiti- tudes, tends to throw thein behind, or in a westerly di- rection, CinMNET CUEEEjifTS. Chimney Currents are produced by the heat of the fire rarefyfng the sur, which rises, and carries the smoke With it. The taller the cMraney ia^ the longer will be the column of rarefied air tending upward j aad, as a conse- quence, the stronger will be the draught. In kindling a fire in a cold chimney, there is very little current till this column becomes heated. The upward motion of heated currents is governed by laws similar to the downward mo- tion of water in tubes, where the velocity is increased witii the height of the head. But as air is more than eight hundred times lighter tlian water, slight causes will affect its currents, which would have no sensible influence on the motion of liquids. For instance, a strong wind striking the top of a chimney may send the smoke down- ward into the room ; and a current can not be induced through a horizontal pipe without connecting with it an ' upright pipe of considerable height. COKSTEUCTION OF CHIMNEYS. In constructing chimneys to produce a strong draught, the throat immediately above the fire, which should have a breadth equal to that of the fireplace, should be con- tracted to a width of about four inches, so that the column 254 MACHIH-ERY IN CONNECTION ■wmi Am. of rising air above may draw the air up tlirough the Fig. 272. tliroat with increased velocity, as shown in fig. 272. This arrange- yj .^^ ment also allows the fire to be built so as to throw the heat more fully out into the room. By leaving the shoulder at 5 square or flat, it will tend to arrest any reversed or downward current in a better man- ner than if built sloping, as shown by the dotted line at a, which would act like a funnel, and throw the smoke into the room. The throat should be about as high as the extreme tip of the flame; if much higher, the chimney will not draw so well, and if lower, too much of the heat will be lost. Fig. 273 shows a fireplace without a contracted throat, the current of which is cotnparatively feeble. Many chimneys draw badly by being made too large for the fire to heat sufficiently the column of air they contain. i -'-^h ^1 A well-built Chimnei/, A badly-built Chimney. CHIMNEY-CAPS. When wind sweeps over the roof of a high part of the building, or over a hill, it often strikes the Fig. 374. tops of chimneys below, and drives the smoke downward. This may be often prevented by placing a cap over the chimney, like that represented by fig. 274, which is supported at its corners, the smoke passing out at the four eides just under the eaves of this cap. But it sometimes happens that there is a confusion of currents and eddies at the top of the chimney, over which this cap CHIMNEY-CAPS. 255 has no influence. In this case, the cap represented by fig. Fig. 275. 275 furnishes a complete remedy, and is, in- deed, perfect in its operation under any cir- cumstances whatever, for the chimney sur- mounted by it will always draw when there is wind from any quarter, with or without a fire. It has <;ffected a perfect cure in some chimneys which before were exceedingly troublesome, and were regarded as incurable. Fig. 276 is intended to show the mode of its Fig. S76. operation ; the wind, as shown by the arrows, being deflected for a Considerable distance on the lee side, so as to fonn a vacancy at a, which the wind from the other end and from the chimney both rush in to supply. Being fixed on without turning iii the chimney, it is both simpler and less noisy than any caps furnished with a vane. EmerBOfrCs Chimney-cap is difierent in constructionj Kg. «7. but quite simi- . pig. 273. I I J lar in principle I _-i — to the preced- JBF I\ ing, it is shown '^i^'ir'^ by fig- 277. A I sheet-iron pipe ■ is set in the top I — ^^^ of the chimney, ~ I furnished with the conical rim, and a plate or fender on the top, which ex- cludes the rain. Between the plate and i-im is a space quite- similar in form or section to that represented by fig. 276. In exposed situations, chim- neys are found to draw more uniformly by contracting 25G MACIIIITERT ix CONNECTION "WITH AIE. the top about a third less thon the rest of the flue. '"^3 Fig. 279. ciin-ei)t at the moment of escape is swifter than below, and less acted upon by any down- ward blast of the wind, at tlie same time that the surface is smaller on which the wind can strike the current, as shown in fig. 278. A chimney of this character may be very easily mndo by contracting the tiers of brick, thus giving to it an ornamental appearance, as seen i;i fisj. 279.* * Where different fires communicate witli tlie earae cliimncy, separate flues sliould be Ijuilt for ciicli lire, and li'ept separate in tlie same clilm- iiey-stacli, carried up independently of eiieli other. But even with this precaution, smoky rooms will not be .avoided, unless the termination of the chimney is of the right form, of which the following illustratiou is given in Allen's Kui-al Architecture ; "Fifteen years aifowe pui'cliascd and removed ihtoa liiost sulistantlal and well-built stone house, the chimneys of which were constructed witli open fireplaces, and the flues carried tip iscpitrately to the top, where they all met upon the same level surface, as chimneys in past times usually were built thus (11;;. 280), Every tireplace in thehouse(and some of them had stoves in) smolied intolcriibly ; so much so, that when the wind was in some quarters, the fires liad to be put out in every room but the liitclicn, whicli, as good luck would have it, erholied less— al- though it did smoke there — than the others. After balancing the mat- ter in our own mind some time whether wo would pulldown and re- build the chimneys altogether, or attempt an alteraliou — as we had given but little tliouglit to the sub- ject of chimney drau:{ht, and to try an experiment w.as the cheapest — we set to work a bricklayer, who, under our direction, simply built ' over each disciiarge of tlie sevenil flues a separate top of fifteen inches high, in this wise : Fig. 281. The -^ remedy was perfect. We have h ul no smoke in the liouse since, blow the wind as it may, on any and on all occasions. The chinineyB canH smoke; nnd the whole expense for four chimneys, with their twelve flues, was not twenty dollars ! The remedy was in giving each outlet a distinct current of air all around, and on every side of it." VBN-TILATIOlir OF ROOMS. 357 VENTILATIOIf. Fig. 28J. Pure atmosplieric air is composed of about 31 per cent of oxygen and 79 per cent of nitrogen ; in addition to >* which, ten thousand parts contain about four parts of carbonic acid gas. This gas, when unmixed, is a deadly poison if breathed, and is fatal to animals even when largely diluted. But the small portion in the atmosphere has no bad effect, and it is safe to breathe double that quantity, or eight parts iu ten thousand. The quantity thrown out from the luhgs is greatly increased by breath- ing, and a number of persons in a close room rapidly poison the air. The air of close school rooms has been examined and found by analysis to contain often from six to twelve times as much carbonic acid as in the pure atmosphere, giving the students dull- ness, headache, and some- times serious maladies. Hence the importance of furnace and open Mre-place ComMneO, the admission of cuirents of fresh air into all occupied rooms, by means of ventilation. In summer, air-currents enter through open doors and windows. In winter, special provision must be made. The following four modes of heating are commonly adopted : 1. By steam radiators, which do not change the air, and its constant admission from without, is in- dispensable. 2. By stoves, which produce a feeble cur- rent up the pipe, and a. con-esponding entrance of fresh air from without through crevices. 3. By warm-air fur- naces, which supply constant and copious cun-ents of warm fresh air, and if properly managed they aflord good ventilation — ^water being freely evaporated to prevent dry- 258 MAGHINEET IN CONNECTION WITH AIE. # ness. 4. By open fire-places, which furnish constant and free ventilation with a loss of about nine-tenths of the heat up the chimney. But if quite small, they are useful in connection with other modes of Fig. 283. heating, in promoting a circulation and change of air. The figure (282) on page 257 shows the manner in which a small fire-place effects the movement of the air of a room warmed with a hot-air register, the air from which rises and intermingles with that of the room, and then descending, passes out at the fire-place. This is one of the simplest and best modes of ventilation on a small scale that can be adopted. Or, if the air of the chimney is heated by the kitchen or other fires, the same good result may be reached by Window ventuaiim. omitting the open fire-place and placing a register in the chimney at the floor, the ascending current in the chim- ney producing a constant draught through the register. If it becomes necessary to admit cold air into a room warmed with a stove or open fire-place, the entrance should be near the ceiling above. If over the window, with a narrow, sloping board to throw the_ current upwards as in fig. 283, the fresh air will be distributed through the room, and ABaayVetauamRoam. ^jy descend towards the fire or stove. But cold air entering low down, as in fig. 284, flows directly to the fire and passes up the Fig. 284. VENTILATION OF BOOMS. 259 cliimney, leaving all the upper portion of the room with undisturbed and stagnant air. The excessive warmth of garrets in midsummer may be avoided by placing a ventilator at the highest part. Fig. 285a. Fig. 8"5. Mode of TentUaling Garrets. Mods of Ventilating Half-story Bed-roomt. and admitting air at windows or openings near the eaves (fig. 285), thus sweeping all the hot air out by the cur- rent produced ; or the oppressive heat of half-story bed- rooms may be similarly avoided, by creating a current of air between the roof and the plastering (fig. 285a). Two modes may be adopted, as represented on each side of the figure. PART IV. HEAT. CHAPTER I. COISTDUCTING POWEE OP BODIES. When any substance or body has become heated, it loses its heat in two diflferent ways, by conduction and by radiation. When conducted, heat passes off slowly or gradually through bodies, as when a pin is held by the hand in a candle, the heat advances from one end to the other till it burns the fingers ; or, when an iron poker is thrust into the fire, the heat gradually passes through it till the whole becomes hot. Iron and brass are, there- fore, said to be good conductors of heat. The end of a pipe-stem may, however, be heated to redness, and a wooden rod may be set on fire without even warming the other extremity, because the heat is very slowly conducted through them. Wood and burned clay are, therefore, poor conductors. The comparative conducting power of different sub- stances may be shown by placing short rods of each with one of their ends in a vessel of hot sand, the others to be tipped with wax. The different periods of time required to melt the wax indicate the relative conducting powers. It will speedily melt on the copper rod ; soon after, on the rod of iron ; glass will require longer time ; stone or earthenware, still longer; while on a rod of wood, it will scarcely melt at all. These rods should be laid hori- zontally, that the hot air rising from the sand may not 260 DTILITY OF THE CONDUCTING POWEK OF BODIES. 261 affect the wax. The conducting powers may be judged of, likewise, with considerable accuracy in cold weather, by merely placing the hfind upon the different substances. The best conductors will feel coldest, because they with- draw the heat most rapidly from the hand. Ii'on will feel colder than stone ; stone colder than brick ; wood, still less so; and feathers and down, least of all, although the' real temperature of all may be precisely the same. UTILITY OF THIS PRINCIPLE. A knowledge of this property is often very useful. For instance, it is found that hiird and compact kinds of wood, •IS beach, maple, and ebony, conduct heat nearly twice as rapidly as light and porous sorts, lite pine and bass-wood. Hence, doors and partitions made of light wpod make a warmer house than those that are more heavy and com- pact. Pine or bass-wood would, in this respect, be better than oak or ash. Porous substances of all kinds are the poorest conduct- ors ; sawdust, for example, being much less so than the wood that produced it. For this reason, sawdust has been used as a coating around the boilers of locomotives, to keep in the heat, and for the walls of ice-houses, to ex- clude it. Sand, filled in between the double walls of a dwelling, renders it much warmer in winter, and copier in summer, than if sandstone were made to fill the same space. Ashes, being more porous, are found to be still better. Tan, which is similar to sawdust, is well adapted to filling in the walls of stables and poultry -houses, where more than usual warmth in winter is required. Confined air is a very poor conductor of heat ; hence the advantage of double walls and double windows, provided there are no crevices for the escape of the confined air. This prin- ciple has been lately applied in the manufacture of hollow brick for building the walls of dwellings. 262 HEAT. The light and porous nature of snow renders it eminent- ly serviceable as a clothing to the earth in the depth of winter, preventing the escape of the heat from below, and protecting the roots of plants from injury or destruction. Hence the very severity of the cold of the Northern re- gions, by producing an abundance of those beautiful feathery crystals which form snow, becomes the means of protecting from its own effects the tender herbage buried beneath this ample shelter. CONDUCTING POWER OF LIQTTIDS. Liquids are found to conduct heat very slowly, and they were for a long time considered perfect non-conduct- ors. Some interesting experiments have been performed i:i illustration of this property. A large glass jar may be filled with water (fig. 286), in which may be fixed an air thermometer, wliicli is always quickly sensitive to small quantities of heat. A shallow cup of ether, floating just above the bulb, may be set on fire, and will continue to burn for some time before any effect can be seen upon the thermometer. The upper surface of a vessel of water itas been made to boil a long time I with a piece of unmelted ice at the I bottom. Liquids are found, how- ever, to possess a conducting power in a very slight degree. When a vessel of water is heated in the ordinary way over a fire, the heat i3 carried through it merely by the motion of its particles. The lower portion becomes warm, and expands; it immediately rises to the surface, and colder portions sink down and take its place, to ascend in their turn. In this way, a constant circulation is kept up EXPANSION BY HEAT. 263 among the particles. These rising and descending cur- rents are shown by the arrows in fig. 287. This result may he easily shown by filling a flask with water into which a quantity of sawdust from som« green hard wood has been thrown, which is abont as heavy as water. It will traverse the vessel in a manner precisely as shown in the figure. These results indicate the importance of applying heat directly to the bottom of all vessels in which water is in- tended to be heated. A considerable loss of heat often occurs when the flame is made to strike against the sides only of badly arranged boilers. EXPANSION BY HEAT. An important effect of heat is the expansion of bodies. Among many ways to show it, an iron rod may be so fit- ted that it will just enter a hole made for the purpose in a piece of sheet-iron. If the rod be now heated in the fire, it expands and becomes larger, and can not be thrust Pi". 2SS. in;o the ho'.e. The expansion may be more visibly shown and accurately measured by means of an instrument called the Pyrometer (fig. 288). The rod a b, secured to its 264 HEAT. jdace by a screw at «, presses against the lever c, anfl this against the lever or index d, both of which Miulti|jly the motion, and render the expansion very obvious to the eye when the rod is lieated by tlie lamps. If the rod should expand one-fiftieth of an incli, and eacli lever multiplies twenty times, then tlic index (or second lever) will move along the scale eight inches ; for 20 times 20 are 400, and 400-50ths of an inch are 8 inches. Many cases showiTig the expansion of heated bodies oc- cur in ordinary practice. One is aiforded by the manner in which the parts of carriage wheels ars bound together. The tire is made a little smaller than tlie wooden part of the wheel; it is then heated till, by expanding, it be- comes large enough to be put on, when it is suddenly cooled with water, and, by its powerful contraction, binds every part of the wheel together with great force. Hogs- heads are firmly hooped with iron bands in the same way, Avith more force thnn could ever be given by driving with blows of the mallet. This principle was very ingeniously applied in drawing together two expanding brick walls of a large building in Paris, which threatened to burst and fall. Holes were drilled in the opposite walls, tlirough wiiich strong iron bars across the building ])roje(.'ted, and circular plates of iron were screwed on these projecting ends. The bars were then heated, which increased their length ; the i)lates were next screwed closely against the walls. On cooling, they contracted, and drew the walls nearer together. The process was repeated on alternating bars, until the walls were restored to their perpendicular positions. All tool<, where the wooden handles enter iron sockets, will hold more firmly if the metal is heated before insert- ing the wood. The metallic parts pf pumps sometimes become very difiicult to unscrew, and a case has occurred where two strong men could not start the screws, until a bystander TIPPECTS OF SUDDEN EXPANSIOX. 263 suggested that the outer piece be heated, keeping the in- ner cool, when a force of less than ten pounds quicklj'- separated them. In other cases, where the large iron nuts have been tjioughtlessly screwed, while wanned with the hands, on the cold metallic axles of wood-sawing ma- chines in winter, they have contracted so that the force of two or three men has been insufficient to turn them. The sudden expansion of bodies by heat sometimes causes accidents. . Thick glass vessels, when unequally heated, expand unequally, and break. Heated plates of cast-iron or cast kettles are liable to be fractured by suddenly pouring cold water upon them. The same ef- fect has been usefully applied in splitting the scattered rocks which encumber a farm, and which are too large to remove while entire. Fires are built upon them ; the up- per surface expands while the lower remains cold, and large portions are successively separated in scales, and sometimes the whole rock is severed. The only care needed is to observe attentively and remove with an iron bar any parts which may have become loosened by the heat, and which would prevent the heat from passing to other portions. One man will thus attend to a large number of fires, and will split in pieces ten times as many rocks in a day as by drilling and blasting. rk'. 289. THE STEAM-ENGINE. The Steam-engine owes its power to the enormous expansion of water at the moment it is converted into steam, which is about 1,600 times its bulk when in a liquid state. The principle on which the steam-engine acts may be understood by a simple instrument, represented in fig. 289. .A glass tube with a small bulb is furnished with a solid, air- tight piston, capable of working up and 12 266 HEAT. do-wn. The water in the bulb, a, is heated with a spirit-lamp or sand-bath ; the rising steam forces up the piston. Now, immerse the bulb in cold water or snow, and the steam is condensed again into water, the tube is left vacant, and the pressure of the atmosjAere forces down the piston. By thus alternately applying heat and cold, it is driven up and down like the piston of a steam- engine. The only difference is, the steam-engine is fur- nished with apparatus so that this application of heat and cold is performed by the machine itself The bulb repre- sents the boiler, and the tube the cylinder; but in the steam-engine, the boiler is separate, and connected by a pipe with the cylinder; and instead of applying the cold water directly to the cylinder, it is thrown into another vessel, called the condenser, connected Avith the cylinder. When Newcomen, who made the first rude regnlnrly working engine, began to use it for pumping water, lie employed a boy to turn a stop-cock co:inected with the condenser, every time the piston made a stroke. The boy, however, soon grew tired of this incessant labor, and endeavored to find some contrivance for relief. This he effected by attaching a rod from the piston or working- beam to the cock, which was turned by the machine itself at every stroke. TLij was the origin of the first self- acting engine. The different parts of a common steam-engine may he understood from the following figures, one representing the boiler, and the othei- the working machinery. The boiler, S (fig. 290), contains water in the lower part, and steam in the upper; F B \% the fire ; v o\s the feed-pipe ; v, a valve, closed by tlie lever b c a, whenever the boiler is full enough, by means of the rising of the float, S, and opened whenever the float sinks from low watei". M, barometer gauge, to show the pressure of the steam ; w, weight on the lever, e b, for holding down the tiafety-valoe : this lever beipg graduated like a steelyard, THH STEA:.r rXGIXE. 21:7 the force of the steam may be accurately weigher!. ZTia a valve opening downward, to prevent the boiler being crushed by atmospheric pressure, by allowing the air to pass in whenever the steam happens to decline. Two Fig. 390. Boiler of Steam-engine. tubes, with stop-cocks, c and d, one just belov the water- level, and the other just above it, serve to show, by open- ing the cocks, whether the water is too high or too low. The working part of the engine is represented in the figure on the following page (fig. 291). The steam enters by the pipe, s, from the boiler on the other side of the brick wall, as shown in fig. 290. The steam jiasses through what is called a four-wat/-cock, a, first into the lower, then into the upper end of the cylinder, C, as the piston, P, moves up and down ; this is regulated by the levers, y y. The piston-rod, E, is attached to the working-beam, S F, turning on the centre, A. The rod, jPi2, turns the fly- wheel, S S, and drives the mill, steam-boat, or machinery to be set in motion. 268 HEAT. The condenser, J, shown directly under the cylinder, re- mains to be described. It is immersed in a cistern of cold water, nnd is connected by pipes with the upper and lower end of the cylinder. Through these pipes the steam Fi'-. Sill. Low-prtssure Sleam-tngine, passes out of the cylinder, first from one end nnd then from the other, and is condensed into water by a jet of cold water thrown into it by the injection-cock. When condense 1, it is pumped out by the pump, O, into the well or reservoir, W, and then again into the feed-pipe of the boilvr. Warm water is thus constantly supplied to the boiler, and effects a great saving of fuel. The supply of sti'am and the motion of the engine are regulated by the governor, G. When the motion is too fast, the two suspended brills, which revolve on a vertical or upright axis, and which hang loosely like pendulums, are thrown out from the axis, producing the movement of a rod which shuts the steam-valve. When the motion QUALITIES OF THE STEA.M-ENGINE. 269 is too slow, the balls approach the axis, and open the valve. Ill highrpressure engines, the steam, is not condensed, but escapes into the open air at every stroke of the piston, , which produces the loud, successive puff^ of" all engines of this kind.. The steam-engine, in its most perfect form, is a striking example of human ingenuity, and its qualities are thus described by Dr. Arnott : " It regulates with perfect ac- curacy and unifoi-mitythe number of its strokes in a given time, and records them as a clock does the beats of its pendulum. It regulates the quantity of steam; the brisk- ness of the fire ; the supply of water to the boiler ; the supply of coals to the fire. It opens and shuts its valves with absolute precision as to time and manner; it oils its joints; it takes out any air accidentally entering parts which should be vacuous; and Avhen any thing goes Avrong which it can not of itself rectify, it warns its at- tendants by ringing a bell ; yet, with all these qualities, and even when exerting a force of six hundred horses, it is obedient to the hand of a child. Its aliment is coal, wood, and other combustibles. It consumes none while idle. It never tires, and wants no sleep. It is not sub- ject to any malady when originally well made, and only refuses to work ^yhen worn out with age. It is equally active in all climates, and will do work of any kind ; it is a water-pumper, a miner, a sailor, a cotton-spinner, a weaver, a blacksmith, a miller, a printer, and is indeed of all occupations ; and a small engine in the character of a steam pony may be seen dragging after it, on an iron rail- way, a hundred tons of merchandise, or a thousand per- sons with the speed of the wind." Steam-engines have been much used on large farms in England for thrashing, grinding the feed of animals, cut- ting fodder, and for other purposes. A successful English fanner has used a six-horse steam-engine to drive a pair 270 HEAT. Fig. 2U2. of mill-Stones, for thrashing and cleaning grain, elevating and bagging it, pumping water for cattle, -cutting straw, turning a grindstone, and driving liquid ma- nure through pipes for irrigating his fields,^ employing the waste steam in cooking food for cattle and swine. In tliis country, where horse labor is cheaper, steam-engines have not come into so general use; but on large farms, where a Wood's Farm Engine. ten horse - power or more is required, they have been employed to much adviintage, consuming no food, and requiring no care Yvj. SIB. ^;'4 WoqpCs Bngim on Wieele, with Hpe Folded Down, when idle. Excellent steam-engines for this purpose are manufactured by A. N. Wood & Co., of Eaton, 271 Madison Co., N. Y., a representation of which is given in the accompanying figure (fig. 292.) When intended to move from place to place, these engines are furnished ready mounted on wheels (fig. 293). The twelve-horse;power engines cost about 11,000, and have thrashed over a hund- red bushels per hour, using half a cord of wood, or 300 or 400 lbs. of coal for ten hours. A Western farmer thrashed 14,250 bushels of wheat in five consecutive weeks, working five and a half days each, with one of these en- gines. The smoke-pipe is guarded, so that straw placed withiu a few inches cannot be set on fire. (See page 293.) More difficulty obviously exists in adapting the steam- engine to plowing than for stationary purposes. In order to possess sufiicient power, when used as a locomotive, the engine must be made so heavy as to sink in common soft soiJ even with large and broad wheels ; and this tendency is increased by the jar of the machinery which these wheels support. For this reason, all locomotive plows have failed. Better success has attended the use of stationary engines, employed for drawing gangs of plows, by means of wire I'ope, across the fields. In Eng- land, where much of the soil is tenacious, and where fuel and manual labor are cheap, and horse labor expensive, this mode of plovvfing has been found profitable when em- ployed on an extensive scale, and is now much nsed. EXCEPTION TO EXPANSION BT HEAT. A striking exception to the general law of expansion by Seat occurs in the freezing of water.* During its change to a solid state, it increases in bulk about one-twelfth, and this expansion is accompanied with great force. Tiie bottoms of barrels are burst out, and cast-iron kettles are split asunder, when water is suflfered wholly to freeze in * There are a very few other substances wliieli expand on passing from a liquid lo a solid state. 272 HEAT. theni. Lead pipes filled with ice expand ; but if it is often repeated, they are crackeassage of a saw. Key, a wedge of wood or metal driven into a mortise or opening, to secure two parts togetlicr. Knee-joint, or Toggle-joint, a contrivance for exerting power or pressure, by stnlighteninga double bar with a joint like that of the Unce. Land, a term applied to the oblong portion of a field tiround wliich the teiim passes in plowing, the field being usually divided into several ion* for this purpose. The term is also applied to the side of a plow opposite the mould board, and a plow is said to run to land when it takes too wide a furrow-slice. Land-side, tlie side of that portion of a plow which mns m the •oil, opposite the mould-board, and next the unplowed portion of ground. Lantern wheel, a pinion made of two small wheels connected by parallel rods wliich form the teeth. 3C6 GLOSS AET. Lever, a bar or rod for raising weights, resting on a point palled a fulcrum. Lever-power, see Sweep-power. Male screw, a screw with a spiral tliread, fitting into a liole witti cor- responding threads called a female na-em. Mechanical powers, the simple machines or elements of machinerj', consisting essentially of the Lever and Inclined Plane ; the lever com- prising the Wheel and Axle and the Pulley, and the inclined plane com- prising the Wedge and the Screw. Mash, or Mesh, to interlock, as the teeth of cog-wlieels. Mechanics, the science that treats of forces and powers, and their action on bodies, and particularly as applied to the construction of ma- chines. Mitre, to cut to an angle of 45 degrees, so that two pieces joined Momentum, impetus; the force of a moving bodj'. Monkey, an apparatus for disengaging and securing again tlie ram of a pile-engine. Mortise, a hole cut to receive the end or tenon of another piece. Nut, a piece of iron furnished with a screw-hole, used on the end of a screw for securing the parts of maeliinury. Overshot wheel, a water-wheel, tlie circumference of which is fur- nished with cavities or buckets, into which the stream of water is deliv- ered at the top, turning the wheel by its weight. Pall, or Pawl, the catch of a rateliet-wheel ; a cliclc- Pent-stock, an upriglit flume. Perambulator, a measurer of distances, consisting of a wheel, and index to show by wheelwork the number of its turns. Percussion, Centre or, that point of a moving body at which its Im- petus is supposed to be concentrated. Pile-driver, or Pile-engine, an engine for driving piles into the ground, effected by repeatedly dropping a heavy weight on the heads o( the piles; used mostly in swamp or water when the bottom is mud. Pinion, a small tootlied wheel, working in tiie teeth of a larger one. Pitch, the distance between the centres of two contiguous cog-wheels. Pitch line, the circle, parallel witii the cireuuiference, whicli passes through the centres of the teeth of a wheel. Pitman, a rod connected with a wheel or crank, to change rotary to reciprocating motion, or the reverse. Planet-wheels, two elliptical wheels connected by teeth running into eacli other, and revolving on tlicir foci. Plow-beam, tliu main timber of a plow, by which it is diuwn. Plow-share, tlie front part beneath the soil, which performs the cut- ting — sometimes caUad plow-slioe, or plow-point. Plunger, tlie jiiston of a forcing pump. Pneu-matics, the science treating of the mechanical jiropertles of air. Pole, the 'ongue of a reaping or other machine. OLOSSART. 307 PowBR, tho moving force of a machine, ns opposed to the weight, load, or resisfciuce of the Bubstiince wrought upon ; also called prime mover. Projectile, a body thrown through the air. Pullet, one of the mechanical powci'S, consisting of a grooved wheel called the sheave, over which a rope passes ; the box in which the wheel is set is called the block. The term is also applied to a fixed wheel over wliich a band or rope passes. PnMP, a hydraulic machine for raising water; or one for withdrawing air. The handle is called the brake. Quantity of motion, the velocity of a moving iody multiplied by its mass. Rabbet, to pare down the edge of a board or timber. Rack, a straight bar cut with teeth or cogs, working into a correspwai- ing cog-wheel, or pinion whieli drives or follows it. Rag-wheel, a wheel with teeth or notches, on which an endless or re- volving chain usually runs. Also applied to a ratchet wheel. Raee-head, the cross-bar of a rake, which holds the teeth. Ram, Htdraulic bam, or Wateb-ram, a hydraulic machine or engine for raising water to a height several times greater thim that of the head of water, by employing the momentum of the descending current in successive beats or strokes. Ratchet-wheel, a wheel cut with teeth like those of a saw, against which a click or ratchet piesses, admitting free motion to the wheel in one direction, but insuring it against reverse motion. Reach, the1)ar which connects the forward and rear axles of a wagon or carriage. Ream, to bevel out a hole. Reciprocatino motion, alternate motion, or a movement backwards and forwards in tlie same path. Reel, the revolving frame of a reaping machine, to throw the stand- ing grain towards the knives. Resolution of forces, dividins a force into two or more forces act- ing in difierent directions ; rendering a compound "force into Its Bevenl simple forces. Resultant, a force produced by the combination of two or more forces. Safett valve, a valve opening outwards from a steiim boiler, and kept down by a weight, permitting the escape of steam when the press- ure rcaclies a certain point, regulated by the degree of weight. The term also applies to a valve opening inwards, and similarly regulated, to prevent the pressure of the atmosphere from crushing-rn the boiler when the steam cools and leaves a vaeunin. Scoop- WHEEL, a water-wheel with scoops or buckets around it, against ivuieli the current dashes. Screw-bolt; a bolt secured by a screw, or with a screw cut upon it. , SCKEW-PBOPELLEB, an instrument for driving a vessel, by means of 3( 8 GLOSSARY. blades twisted like a screw, revolving beneath the water, the axis being parallel witli the Iveel. Section, one of the knives or blades on the eutter-bar of a mowing machine. Selfhaker, ;i contrivance attached to a reaping macliine, to throw off the cut strain in s^'vcls, to obviate raking off by hand. SnEAiiS, or Sheers, two poles bished together like the letter X, for placing under heavy poles, etc., in raising them ; also to single vertical poles suppoi-ting pulleys, for a similar puipose. ' Sheave, the wheel of a pulley set in a block. Shoot, or Shute, a passage-way down which grain, hay, or straw, is slid or thrown. Side-draught, the side pressure of a machine on the team which draws it, as distinguished from centre draught. Sinole-tbeb, a single whiffle-tree, the cross-bar to which the traces of a horse are attached, as distinguished from a doubletree, or two-horse whiffle-tree. Siphon, or Stphon, a bent tube for drawing off liquids; the column of liquid in the outer or longer leg overbahineing the inner column, and producing a current. Sebin, tlie iron casing of a wagon-axle on which the wheel runs. Skim-coulter, a coulter of a plow so constructed as to pare the sur- face before tlie mould-board. Skim-plow, the small forward mould-board of a double Michigan or Sod-and-subsoil plow. Slidb-kest, the rest or support of the chisel in a turning lathe, made to slide along the frame for cutting successively the different parts of the work. Slot, a slit or oblong aperture in any part of a machine, to admit .in- other part. Snath, the handle or bar to which the blade of a scythe is attached. Sod, the slice of earth cut by the passing of a plow. Sole, the bottom plate under a horse-shoe tile, in draining. Spindle, a small axle in machinery, as distinguished from a shaft or large axle. Spirit-level, a glass tube containing alcohol with an air-bubble, her- metieally sealed at both ends, the position of the bubble at tlie niiddla showing the tube to be leveL Spur wheel, or pinion, a cog-wheel with teeth parallel to the axle. Standard, an upriglit supporting timber; the front upright bar in a plow to which the mould-board is fastened. Steam chest, u. box attached to the cylinder of a steam-engine, in wliich the sliding valves work. Stirrup, an iron band encasing a wooden bar, for attaching to some other part. Stud, a short, sto it support. GLOSSARY. 309 SoBsoiL-PLOw, a plow rannmsr below the lurrow of a common plow, for brcaUin^ up or loosening the subsoil or lower soil of a fluid. SwAOE, lo give shape to a substance by stamping with a die. , SwEKP-POWEU, a horse-power for drivin;^ thrashing and other ma- cliincs, wiiere the horses are attached to a pole and walli in a eiicle. • Swingle-tree, also called swing-tree, single-tree, whipple-tkee, and WHIFFLE-TREE ; the cross-bar to which traces are att:iched. SwiNO-PLOW, a plow with no wheel under the beam. Swivel, a ring and axis in a eliain, to admit of its turning. Swivel bridge, a bridge which turns round sideways on its centre. Swivel plow, a side-hill plow, ora plow with a reversible mouUl-board. Tackle, a pulley, or machine with ropes and blocks for raising heavy weiglits. Tail-race, the channel which carries oflf the water below a water wheel. Tedder, a macliiue for turning and spreading ha)-. Thill, one of the shafts of a wagon between which the horse is put —often corrupted to MR. Throttle-valve, a valve which turns at lU centre on .in axis — gener- ally used to regulate the supply of steam to the cylinder of a steam-en- gine. Thumb-screw, a screw with its head flattened in the direction of its length, so as to be turned with the thumb and finger. Tide- wheel, a wheel adapted lo currents flowing both ways — the float- boards pointing from the centre. Tine, the tooth or prong of a forli. TiBE, the iron band which binds together the fellies of a wheel. Toggle-joint, or knee-joint, a mechanical power exerted by straight- ening a double bar with a hinge at tlie middle or connection. Torsion, the act of twisting by the application of lateral force. The force of tarsioH is the elasticity of a twisted body. Track-cleaner, an attacliTnent to a mowing maeliine, to throw the cut grass away-from that which is uncut. Traction, Angle op, the angle between the line of draught and any given plane, as that of the earth's surface. Trammel, an instrument used by carpenters for drawing an ellipse. Tread-power, a machine on which the liorse or other animal working it walks. It may be either a horizontal or slightly inclined wheel ; or an endless-chain power, the term being more frequently applied to the latter. Trench-plow, a plow cutting deep furrows and bringing the subsoil np to the surface; as distinguished from a subsoil plow, which only loosens the subsoil and leaves it below the surface. TRnNDLE-HEAD, a whccl turning a mill-stone. Tdb-wheel, a horizontal water-wheel, diiven by the percussion of the stream against its floats, and not submerged in water. 310 GLOSSARY. Tumbler, a latch in a lock, which, by me:ms of a epriug, dclaiiia llie bolt ill its piiice until lifted by the key. Tumbling kod, the rod which connects the motion of a liorse-power Willi tliat of a tlii'asliing or oiher machine. Turbine wheel, a horizontal water-wlieel, so constructed that the current strikes all the floats or buclcets around the circumference iit the same time, thus imparting to it ^reat power for its size. It is sub- mer^jed, the water escaping' towards the centre and below, or above and below togetlier. Undeushot wheel, II water-wheel moved by tlie current striking agiiinst the lower portion of its circumference. Univehsal joint, a uonnecting joint between two rods, consisting oi a sort of double hinge, admitting; motion in any direction. Valve, a lid for closing an aperture or passage, so as to open only In one direction. Velocity, speed or swirtncss; which may be uniform, or equ:il throughout; accelerated, or increasing ; or retarded, or rendered slower. Virtual velocities, Principle of, that by which ccriaiii jiowcrs are equal to each other, wliere the force and space moved over, whatever these may be, are the siime when multiplied together. Washer, a circular piece of mefeil, pasteboard, or leather, placed be- low a screw-head, or nut, or within a linch-pin, for protection. Wateu-ram, see Ram. Whifele-tkee, or Whipple-tree, the cross-bar to which the traces of a horse are attached ; see Single-tree. Whip-saw, a large saw, worked by a man at one end, with a wooden spring at the oilier ; a cross-cut saw. Winch, a bent handle or right-angled lever, for turning a wheel or grindstone, or producing rotary motion for other purposes. Windlass, a machine for raising lieavy weights, by the winding of .1 rope or chain on a horizontal axle, and turned by a winch or by levers. WiNUOW, or Windrow, the liilire of hay raked up on a meadow. Wrest, a partition which determines the I'oriu of the bucket in an overshot wheel. INDEX. A Air, Pressure of 239 " Mode of weighiug .^ 239 •' Pnmp ..240 " Hand fastened by 241 " Hotiou of. 245 '• Resistance of. 347 Alden's Cultivator 146 Allen's Farm Mill 195 Altitncles measured by the Barome- ter a43 American Hay-teddiug Machine 165 Apparatus for Experiments 2S1 Aqueducts of the Romans 199 Archimedean Root Washer 193 " Screw 217 Archimedes, would move the earth with a lever 55 Artesian Springs and wells 201 Atmosphere, Height and Weight of 239,241 B Bags, How to carry 41 Balance, a lever. 47 Balls, Why they roll easily 38 Barometer 241 Bars of wood, Strength of. 79 Beardsley's Hay Elevator 177 Bellows, Hydrostatic 204 Bevel Wheels or Bevel Gear 60 Billings' Corn Planter 155 Binders for Reaping Machines 163 Boat, Compound motion of. 20 Broadcast Sower, Seymour's 154 Brown's Wind-mill 251 Brush Harrow 142 Buckeye Mower 159 Bullard's Hay-tedding Machine 165 Bulk of a ton of different 8ubstances.210 Burrall's Com-sheller 191 C Capillary attraction . 31 " " its groat import- ance 33 Caynga Chief Mower 160 " " Dropper 162 Cements, Effects of. 28 Centre of Gravity 34 " " curious examples of 33 " how determined 35 Centrifugal Force 21 Chain Pump 231 Cheese Press 73 " '■ Dick's 74 " " Kendall's 73 Chimney Currents 253 " Caps 2.54 Chimneys, Construction of 254 " To prevent smoking 256 Churn with fly-wheel 17 " worked by dog-power 191 Cistern Pumps 219 Cistertis, To calculate contents of. .2.37 " Proper sizes for 238 Clod Crusher 149 *' " Croskill's and Ameri- can 150, 151 Cog, Hunting 60 Cogs, Form of 58 " and Cog-wheels 58 Cohesion, Attraction of 27 " between lead balls 27 " weak in liquids 31 Complex Machines, objectionable. .116 Compound motion 19 ^' " How to calculate. 20 Comstock's Rotary Spader. . . .148, 117 ■Conducting i)ower of bodies..... ..260 " liquids 261 CornHuskors 288 " Planters 105,191 3ia IXDEX. Corn Sheller, Horse-power 192 " " Richards' 1!)2 Corn Planters , 155, 285 Cost of Implements and Machines. 117 Cotton Gin, Emery's 190 Conlter for Plows 127 Crested Furrow-slice 12(i Crosskill's Clod-crusher 150 Crow-bar, a simple power 4;^ Crownwheels 60 Cubic foot of different substances, Weight of 210 Cultivator, or Horse-hoe 145 Claw-toolhod 14« Alden's Thill 146 " Bucli-foot 146 " Two-horse 148 " Harrino;ton's 157 Cutter for the Plow 127 " Bar in Mowers and Reapers. 158 D Dederick's Hay-press ISi " Capstan 185 Deep-tiller Plow, Holbrook's 126 Deep Wells, Pump for 220 Dew and Frost 278 Discharge of water through pipes.. 284 " " Rule fen- 385 Ditches, Velocity of water in. .214, 286 " Leveling instruments for. .115 Dog-power Churn 191 Dranght, Combined 96 Draught of wheels, explained 37 " Line of , . . 95 " Princii)le8 of 9.3 " How to measure 94 " of Plows 95 Drilling wheat 153 Drills, Hand 157 Drive-pump 220 Dropper, attachment to reapers 162 Dynamometer, applied to roads 85 " Construction and use of 98 " Self-recording 101 '• Waterman's 102 " for rotiiry motion... 106 E Elevators for Hay 173 Emerson's Chimney Cap 255 Emery's Horse-powers 188 " Cotton Gin 196 Empire Wind-mill 251 Endless-chain power 188,189 Engine, Garden 230 Experimenis, apparatus for .281 • F Falling Bodies, Velocity of 23 " " Resistance of airon 25 '* " in vacuo 25 Farm, Seventy-thoiisand-acre 8 '■ implements. Construction and use of. 115 " implements. Cost of 117 " mills 19.T Finger-bar in mowers and reapers. .1.58 Flail, Olil sort 187 " Estimate of comparative work with 187 Flash-wheel 281 Flea, power of leaping 115 Fly-wheel 16 '• used on horse-])ump 16 Forcing-pump 22;i Fork Handles, Proper form of 76 Foreman's Farm Mill 195 Friction 81 " Nature of 82 '• How to Measure 83 " not^iifluenced by velocity. 88 " of axles 89 '■ of wheels 90 " Lubricating substiinces for. 91 " Advantages of 92 Frost and Dew 278 " In valleys 279 Fuel, Green wood for 275 Furrow-slice. Crested 126 Furrows, Lapping and flat 127 Galileo's experiment on falling bod- ies 26 Garden Engine 230 Garrett's Horse-hoe 147 Geddes' Harrow 143 Gladding's Hay-fork 175 Glossary of terms 287 Gravitation a"! Gravity, Centre of. 34 INDEX. 313 Gravity, Specific, how measured.. ,208 " '^ or different sub- stances 209 Green wood for fuel 274 Hand-drills 157 Harrington's Sower and Cultivator. 167 Harrow, Disc 283 " Morgan— Norwegian 144 *' Scotch, or square 143 Spring-toothed 283 " Thomas Smoothing 284 Harvester, Marsh s. . ; . . . . 163 Hay forks, Horse . .173 carriere 180 loadei-s 186 take, Revolving... 168 " Warner's 169 takes. 166, 167 stacking machine 181 loaders 287 presses 184 " horizontal 288 tedders 165,168 sweep 171 Headers 163 Heat, Properties of. 260 " Expansion by 263,271 " Latent 273 " Radiation of 276 Hicks' Hay-carrier 180 High pressure steam-engines 269 Hoe-handle, Proper form of 77 Holbrook's Plow 125 " Swivel or side-hill Plow.133 Hotse, day's work at different de- grees of speed 110 hoe, Garrett's 147 power. Estimating 109 Hay-forks, Operation of. . . .174 fork, Gladding's 175 " Palmer's .176 " Myers' 177 " Beardsley's 177 " Raymond's 178 *' Harpoon 179 '• Walker's 179 " " Sprout's 179 Hydraulic Ram 326 " " Regulating 227 Hydrostatic Paradox 203 Hydrostatic Bellows 204 Press 203 Hydrostatics 198 Implements required for the farm. . 7 9,11T " Construction and use of 115 Improvements in Farm Machinery. 8 Inclined Plane ,*... 63 Inertia 11 " apparatus 18 " Effects of, on wagons 13, 17 J Joint, Universal 60 K Kirby Mower and Reaper 159 Reaper, Hand-ralce for KiO Self-raking 161 Knee-joint, or Toggle-joint 71 Knives in mowers and reapers. Form of 15S Kooloo Plow 118 Labor, Application of 108 " of men and horses 110 Ladders, Self-supporting 40 Lapping and flat furrows 127, 138 Latent heat 273 " " Advantages of. 275 Law of virtual velocities 43 Leveling Instruments 215 Levers 45 " of the second kind 45 " " .first kind 46 " " third kind 46 " Calculating power of. — 49,50 " Examples of. 46 " Combination of 50 Line of direction 36 Liquids, Velocity of, in falling 211 " Discharge through pipes. .212 Loads on sideling roads , 37 Lubricating substances ^0 3U INDEX. in Machinery in connection with water.lOS Machines, Advantages of 42 Modelsof. 113 " Complex, objectionable. .116 " Construction and use of. .115 " Required for the Farm . 7, 9,117 Marsh's Harvester 163 Materials, Measnring strength of . . . 29 Mech^ical powers 43 " principles, Advantages of 10 Mechanical principles, Application of 75 Models of machines 113 Moline Plow 120 Momentum 14 " Calculating quantity of.. 18 " of railway trains 18 Moorish Plow 118 Morgan's Harrow 144 Motion, Compound 19 Mouldboard of the Plow, Form of.. 124 Mountains, Height of, measured by barometer 243 Mowing Machine, Wood's 168 " " Kirby's 159 " " Buckeye 159 " " Cayuga Chief.... 160 Mowing Machines, Construction of.l58 " " How to select. . . 164 Myers' Horse-fork 177 N Norwegian Harrow ....144 O Ogle, inventor of the Finger-bar... .169 Ox-yokes 78 P Packer's Stone Lifter 62 Palmer's Horse-fork 176 " Hay-stacking Machine. . . .183 Paradox, Hydrostatic 203 Pile Engine or Driver 15 Pinions, Operation of 60 Pipes., To determine strength of 200 "" Discharge of water throagh. Pitts' Straw-carriei »nd Thrasher... 190 Plank roads. Amount of resistance on 81,80 Planting Machines 152 Plaster Sower, Seymour's 155 Platform Scales 62,63 Plow, Chilled 2S2 " Kooloo— Moorish 118 " German 119 ** Modern improved 119 " Moline Steel 120 " Woodruff & Allen's 130 " Double Michigan 131 " Mole 139 " Ditching 138 " Side-hilior Swivel 132 " Subsoil 133, 135 " Trench 134 " Paring 137 " Gang 137 " Defects in 122 *' Character of agood one 121 " Cntting edge of. '.121 " Resistance of different parts.. 122 " Form of the mouldboard 124 " Appendages to 140 " Wheel coulter and Hook 140 " Sulky 283 Plowing, Operation of. 128 " Fastandslow 130 *' Requisites for success in..] 29 Potato Planter, True's 156 " Digger 144 Power of a horse. Estimating 110 Press, Hydraulic 205 Presses for hay 184 Pressure of liquids, Determining... 203 " Upward, Measuring 199 " " in liquids 198 Pulley .- 61 Pulverizers 142 Pump, Cistern 219 " Non-freezing 219 " Drive 220 " fordeep wells 230 " Chain 221 " Rotary 223 " Suction and Forcing 223 Pumping water by wind 248 Pumps, Construction of 218 Pyramids, Firmness of 38 I^rometer, how made ..... 2fiS INDEX. 315 R Rake, Simple form of, 167 " Kevolving 108 " Warner's 109 " Spring-tooth 170 " " " Hollliigsworth's.l71 Ram, Hydraulic 226 Raymond's Hay Elevator 17S Reaping Machines daring the war. . 8 " " Self-rakers for. .101 " " Headers 163 " Self-binding.... 286 Revolving Hay Rake .168 Roads, importance of good ones.... 08 " Hov? to form the bed of 07 " Measuring the friction on. . . 84 ** Amoant of resistance on 86 " Goodandbad 69 " Ascent in 63,66 " Cost of going up and down hill 65 Rocks, Machines for removing 69 Rockers, How to make 41 Rollers 152 Rolling Mill, Principle of 74 Root Washer 193 " Slicers 194 Sotary Spader, Comstock's 148, 117 " Pump 222 S Sack-barrow, a lever 48 Sap, Ascent of. .33 Scotch or Square Harrow 143 Screw 70 " Archimedean 217 " Estimating power of. 71 Seed Sower 153 " " Harrington's 157 Self-raking Reapers IRl Seymour's Broadcast Sower 154 Shares' Harrow 145 Side-hill or Swivel Plow 133 Single-tree, Wier's 98 Sowing Machines 152 Specific gravities, how determined. 208 " " Table of. 209 Springs of water 201 Stacks, Building by machinery 1S2 Btcam engine, Construction of.265, 267 " " for farm purposes.. ..370 Steel Plows 120 Steelyard 47 Stone-lifter 63 Straw-cutters 16, 7S " carrier, Pitts' 190 Strength of materials 39 " " wood, iron, and ropes. 30 " "rodsandbars 79,80 " " pipes. To determine... 200 Stubble Plow, Holbrook's 126 Stamp-puller 64 Subsoil plowing 133 " Plows 135 Swivel Plow 133 Syphon 244 " nsed for draining 243 T Teeth of wheels 58 Thill-cultivator, Alden's 146 Thrashing by machinery 187 " machine, Comparative cheapness of. 183 Thrashing machine, Endless-chain power for 188 Thrashing machine, Pitts' 190 Toggle-joint power 71 Tread horse-powers 188 " " " To determine work of 188 Turbine Water-wheel 233 " " " Reynolds' 224 " " " Van de Wa- ter's 2J4 CJ Universal joint 60 Upward pressure of liquids 198 V Vacuum, Machine ninning in 11 Velocity affects friction but slightly. SS " of falling water 211 " of water in ditches .... 214, 28B " " through pipes 284 Ventilation 257 " through walls and gar- rets 253 Ventilator, Griffith's 35& " Emerson's ...266 Virtual velocities, Law or rule of... 43 316 INDEX W Wagon springs. Advantages of. 17 " wheels, Proper width for. . . . 87 Wamer^s Revolving Hake 169 Washing Machine 72 Water, Remarkable effects of heat on 279 Water, Velocity of 311, 213 " Discharge of, through pipes, 212 " in ditches 214 " wheels. Turbine 223 " ram 226 ** engines 230 Waves, Nature of. 282 " Velocity of 234 " Breadth and height of. 233 " To prevent inroads uf . . 335, 236 Weatherglass 243 Wedge 69 Weed hook on plows 140 Weighing machine, or platform scales 62,88 Wheat drill 163 " " Bickford & Huffman's, Constraction of 158 Wheel and axle 55 " " " Modifications of 67 Wheelbarrow, Operation of 47 Wheel-cntter to plows 140 Wheels, large ones run best 39 *' for wagons Proper width for 8T Whiffle-treep for three horses 50, 97 Wind.Cansesof 252 Velocity of 346 mills 317,289 " Pumping water by 248 " Brown's 251 Wooden legs, why hard to walk on, 40 Wood's Plow 119 Work of men and horses, Eatima- tlng 110 FAHlti HOMES. HSr-DOORS AND OUT-DOORS. By E. H. LELAND. IliliVSTKATEO. This is a most charming hook, and shoald be in every farm homo in the land. It is written in a most captivating style by a writer thoroughly familiar with the subjects treated. Bvery page aboands in yalnable hints and sugges- tions, communicated in an entertaining, narrative form. The volume is very handsomely printed on tinted paper, bound in extra cloth, beveled edges, black and gold. THREE SAMPLE CHAPTERS. CHAPTER I.-Bnii.OTNa.-The Site-The Plan— The Four Essentials-Sun- light— Halls— Bath-rooms- Ventilation -Drainage and Preventable Filth. CHAPTER II.— FraisHtso. —Calcimine— An Excellent Whitewash— Borders —Wood-work— Mantels— Hall Windows, CHAPTER III.— FnKNisHwo.-The Spare Bedreom— The Boys' Room— The Old People's Room— Mother's Room— The Girls' Room— The Dining-room— The Parlor. In addition- iTiere are entertaining and instructive Chapters upon the following, among other topics; Farmers' Wives.— Farm Neighborhoods.- The Dairy-Room and Butter-Making.— Window Plants.— The Vegetable Garden.— Small Fruits and Garden Fruit Trees. -The Best Foods and some Best Methods of Preparing Them.— A Few Simple Luxnries. PRICE, POST PAID, $1.50. THE SADDLE-HORSE. A Complete Guide for Riding and Training. This is a complete and reliable Guide- Book for all who desire to acquire the accomplishment of horsemanship, and who w sh to teach their animals how to perform various feats under the saddle. 12mo. Handsomely Illustrated. Tinted Paper. PRICE, POST-PAID, $1.00. O. JUDD CO., DAVID W. JUDD, Pres't. SAM'L BURNHAM, Sec. 751 BKOABWAY, NETT fORK. This is a valnable work which meets the wauts ol" persons of moderate meaus, and will, it is helieved, prove one of the Most Popular Architectural Books ever isBoed. It gives a wide range of design, from a dwelling costing $350 up tc $8,000, and adapted to farm, village, and town residences. Nearly all of these plans have been tested by practical workings. They provide for heating, ventila- tion, etc., and give a large share of what are called. Modem Improvements. One featare of the work imparts a value over any similar publications of the kind that; we have seen. It gives an Estimate of the Quantity of Every Article Used in the coiietniction, and the «w^ of each material at the time the building was erected, or the design made. Even if prices vary from time to time, one can, ft'om these data, ascertain within a few dollars, the probable cost of couetmcting any one of the buildings here presented. PROFUSELY ILLUSTRATED. 12mo. PRICE, POST-PAID, $1.50. O. JUDD CO., DAVID W, JUDD, Pres't SAM'L BURNHAM, Sec. ■5 51 ISROAOWAT, TflZ'^ VORK, Talks on Manures. A Series of Practical and Familiar Talks between the Author and the Deacon, the Doctor, and other Neighbors, ON THE WHOLE SUBJECT OE MANURES AND FERTILIZERS. By JOSEPH HARRIS, M.S., Autluk of "Walks and Tailcs m the Farm," "Harris m the Mg," etc. Including a Chapter specially written for it by Sir John Eennet Lawes, of Eothamsted, England. There is scarcely any point relating to fertilizing the soil, including the Bnitable manures for special crops, that is not treated, and while the teachings are founded upon the most elaborate scientific researches, they are to far di- vested of the technical language of science as to commend themselves to farm- ers as eminently " practical." It is not often that the results of scientific in>- vestlgatlons are presented in a manner so thoroughly popular. CLOTH, 12mo. PEICE, POST-PAID, $1.75. O. JUDD CO., DAVID W. JUDD, Pres't. SAM'L BURN HAM, Sea 751 BROADWAY, NEW IfOBK. KEW AMERICAN FARM BOOK. OIlIQOrALI.7 BT AVTHOB 01" "DI3BASK3 OF DOMESTIO ANIMALS," AMD rOBMEBLT SDITOB ©» THE "AMEBICAK AQBICULTUBIST. " EEV13BD AND ENLARGED "BT LEW^IS F- ALLEN, AUTHOB OF "AMERICAN CATTLE," EDITOR OF THE "AMERICAN SHORT-HOB HERD BOOK," ETC. C O TvT T E N T S : Intboduction. — Tillage Husbandry — Grazing — Feeding — Breeding — Planting, etc. Chapter I. — Soils — - Classiacation— Description — Management — Pro- perties. Chapter II. — Inorganic Manures — Mineral — Stone — Eartli — Phos- phatic. Chapter III. — Organic Manures — Their Composition — Animal — Ve- getable. Chapter IV. — ^Irrigation and Drain- ing. Chapter V. — ^Mechanical Divisions of Soil^ — Spading — Plowing — Im- plements. Chapter VI. — The Grasses — Clovers — Meadows — Pastures ^Compara- tive Values of Grasses — Implements for their Cultivation. Chapter VII. — Grain, and its Culti- vation — Varieties — Growth — Har- vesting. Chapter VIII. — Leguminous Plants —The Pea— Bean — English Field Beau^Tare or Vetch— Cultivation —Harvesting. Chapter IX. — Roots and Esculents — Varieties — Growth — Cultivation — Securing the Crops — Uses — Nutri- tive Equivalents ot Different Kinds of Pora^. Chapter X. —Prui ts-Apples— Cider — Vinegar — Pears — Quinces — Plums Peaches — Apricots — Nectarines — ■ Smaller Fruits— Planting— Cultiva- tion— Qatherin"— Preserving. Chapter XI.— Miscellaneous Objects of Cultivation, aside from the Or- dinary Farm Crops — Broom-corn — Flax---Cottoa— Hemp — Sugar Cane Sorghum — Maple Sugar —Tobacco — Indigo — ^Madder— Wood— Sumach- Teasel — Mustard — Hops — Castor Bean. Chapter XII.- Aids and Objects of Agriculture — Eotation of Crops, and their Effects— Weeds— Restora- tion of Worn-out Soils— Fertilizing Barren Lauds— Utility of Birds — Fences — Hodges — Farm Roads — Shade Trees— Wood Lands— Time of Cutting Timber — Tools — Agri- cultural Education of the B'armer. Chapter XIII. — Farm Buildings- House — Barn — Sheds — Cisterns — ^ Various other Outbuildings— Steam- ing Apparatus. Chapter XIV.— Domestic Animals — ^Breeding — Anatomy— Respiration — Consumption of Food, Chapter XV.— Neat or Homed Cattle Dcvons — Herefords — Ayreshires — Galloways — Short -horns — Alder- neys or Jerseys— Dutch or Holstein — Management from Birth to Milk- ing, Labor, or Slaughter. Chapter XVI.— The Dairy-Milk— Butter — Cheese — Different Kinds- Manner of Working. Chapter XVII. — Sheep — Merino — Saxon— South Down — The Long- wooled Breeds — Cotswold — Lincoln — Breeding — Management — Shep- herd Dogs. Chapter XVIII. — The Horse— De- scription of Different Breeds — Their Various Uses — Breeding — Manage- ment. Chapter XIX. —The Ass— Mule — Comparative Labor of Working Animals. Chapter XX. — Swine — Different Breeds — Breeding— Rearing — Fat- tening— Curing Pork and mms. Chapter XXI. — Poultry — ^Hcns, or Barn-door Fowls — Turkey ■ — Pea- cock — Guinea Hen — Goose — Duck — Honey Bees. Chapter XXII Diseases of Ani- mals—What Authority Shall Wo Adopt ? — Sheep — Swine — Treat- ment and Breeding of Horses. Chapter XXIIL— Oonclnsion- Gene- ral Remarks — The Farmer who Lives by his Occupation— Th3 Ama- teur Farmer— Sundry Useful Tables. SENT POST-PAID, PRICE $2.50. O. JUDD CO., DAVID W. JUDD, Pres't. SAM'L BURNHAM, Sec. 761 BBOAD'n'AY, NE^T TOBK. A Practical Treatise on the Sheep. DESIGNED ESPECIALLY POU AlVLERIOAIsr SHEPHERDS. By HENRY STEWART. Illustrated. This' Manual is designed to be a hand-book for American ebeplierds and farmers. It is intended to be so plain that a farmer, or a farmers son, who has never kept a sheep, may learn from its pages how to manage a flock successfully, and to be so complete that even the experienced snej)- herd may gather some suggestions from it. The results of personal experi- ences of some years with the characters of the various modern breeds of sheep, and the sheep-raising capabilities of many portions of our extensive territory and that or Canada, most of which have been visited with a view to the effects upon our sheep of the varying climate and different soils ; and the careful study of the diseases to which our sheep are chiefly sub- ject, with those by which they may eventually be afflicted through unfore- seen accidents ; as well as the methods of management called for under oar circumstances, were finally gathered into the shape in which they are here presented to the shepherds of America, with the hope that they may he as acceptable and useful to them as they would have been, when he first undertook the care of a flock, to The Author. CO rsTTBITTS. CHAPTER I.— Thb Sheep as an Industrial Prodttct.— Antiquity of Sheep Husbandry— The Future ofSheepHusband ry— Its Effects upon Agriculture —Demand lor Mutton Sheep— Value of the Wool Prodact— Extent of Pasturage in America. CHAPTER II.— The Summer Manasemrn tof a Flock.— Selection of a Sheen Farm— Effectsol Soils upon the Health of Sheep— Whatis a Uood Pasture? —Value of Certain Grasses— The Western Plains as Sheep Pasture— Pastures —Fodder Crops- Root Crops- Folding Sheep— Dog Guards. CHAPTER III.— Manaoement of Ewes and Lastbs.- Marking Sheep— Record for Breeders— Management of Kams— Care of Ewes— Care or Lambs- Selecting Lambs lor Breeders- Prevention of Disease— Dipping Prevent- ive of Parasites. CHAPTER IV.— WrtTTEs Manaoement of Sheep.- Barns and Sheds— Feed Racks— Feeding Value of Different Fodders, Roots and Grains— Exuen- ments In Feeding— Profit of Feeding— Raising Early Lambs lor Market- Feeding Sheep for Market— Value of Manure— Markets lor Sheep. CHAPTER v.— Breedino and Breeds of Sheep.— How Breeds are Estab- lished—Improvement of Flocks — Cross Breeding — Breeding lor Sex- Maxims for Breeders— Native Breeds— Improvement of the Merinos- The Merino Fleece— Long-Wool Breeds— Medium and Short-Wool Breeds- Foreign Breeds— Cross-bred Sheep— American Cross-breeds. CHAPTER VI.— The BteuOtuee and Uses of WooL.-^The Method ol Growth olWool— Its PeculIarStmcture— Its Composition— The Tolk-Classlflcation of Wools— Character ol Merino Wool— washing Wool— Shearing— Packing and Marketlnethe Fleeces— Production ol Wool In the World— Compara- tive Values ol wool In Different Countries— Favorable Conditions lor Pro- ducing Wool in the United States. CHAPTER VII.— The Anatomy and Dtseases of the Sheep.— Physiology of the Sheep— The Teeth— The Bones— The Vital Functions, Respiration, Cir- culation, and Digestion— The Causes and Prevenlion of Diseases ol the Sheep— Diseases 01 the Respiratory Organs j of the Digestive Organs ; ol the Blood— Enzootic Diseases— Epizootic Diseases— Diseases of the Urinary and Reproductive Organs ; ot the Brain— Parasitical Diseases of the Intes- tines i ol the Skin- Diseases ol the Feet— Diseases Incident to Lambing— Special Diseases — Diseases ot Lambs. Table of Approximate Equivalent Measures. Price, post-paid, $1.50. O. JUDD CO., DAVID W. JUDD, Pres't. SAffl'L BURNHAffl, Sec. T51 BROADW^AY, NEW YORK. GARDENING FOR PROFIT: A GUIDE TO THE SUCCESSFUL CULTIVATION OF THE MARKET AND FAMILY GARDEN. By Peter Henderson. This work has had a conetant and remarkable sale ever since it was issued, and the later enlarged and revised edition is as well received as was the first. It was the first work on. Market Gardening ever published in this country. Its author is well known as a market gardener of many years' successful experience. In this work he has recorded this experience, and givea without reservation, the methods necessary to the profitable culture of the It is a work for which there was an urgent demand before Its Issue, and one which commends itself, not only to those who grow vegetables for sale, but to the cultivator of the to whom it presents methods quite different from the old ones generally practiced. It is an oniGiNAL and purelt American work, and not made up as books on gar- dening too often are, by quotations from foreign authors. Every thing is made perfectly plain, and the subject treated in all its details, from the selection of the soil to preparing the products for market. CONTENTS. Men fitted for the Business of Gardening: The Amount of Capital Kequired, and "Working Force per Acre. Profits of Market Gardening. Iiocation, Situation, and Laying Out. Soils, Drainage, and Preparation. Manures, Implements. Uses and Management of Cold Frames. Formation and Management of Hot-beds. Forcing Pits or Greenhouses. Seeds and Seed Kaising. How, When, and "WTiere to Sow Seeds. Transplanting Insects. Packing of Vegetables for Shipping. Preservation of Vegetables in "Winter. Vegetables, their Varieties and Cultivation. In the last chapter, the most valuable kinds are described, and the cnltnie oroper to each is given in detail. Sent post-paid, price $l.50. O. JUDD CO., DAVID W. JUDD, Pres't. SAffl'L BURNHAM, Sec. 751 BROADWAY, NEW" YORK. Hardening for Pleasure. A GUIDE TO THE AMATEUR IN THE Fbuit, Vegetable, and Flower Gaeden, ■WITH FULL DIRECTIONS FOR THE greenhouse, conservatory, and window-garden. By Petek Hendersok. AUTHOR OF "GARDENING FOR PROFIT," AND " PRACTICAL FLORICULTURE." Illustrated. EDITORIAL NOTICES. One of the most popular works of recent years on similar topics was the "Gardening for Profit" of Mr. Peter Henderson, the well-known florist of Jersey City. He has been equally fortunate in the title of a new book from his pen, just published by the Orange Judd Co., of New-York — "Gardening for Pleasure." The author has a happy faculty of writing for the most part just what people want to know— so that, although his books are neither exhaustive nor especially elaborate, they proceed to the gist of the subject m hand with so much directness and simplicity that they nil a most important and useful sphere in our rural literature.— Z'Ae Cultt- vator and Country 6/enUeman, Mbanij, N. Y. It gives, in a clear, intelligible form, just the information that novices and even experienced cultivators wish to have always accessible, and will be specially valuable to those who keep house plants. — 2'Ae Observer, Neiv- York City. Mr. Peter Henderson has followed up " Gardening for Profit " with "Gardenino; for Pleasure,", into which is packed much useful information about window-gardens, the management of flower-beds, etc. — 2%e Inde- pendejU, Mew- York City. He is a thoroughly practical man, uses plain, common language, and not technical terms, in his statements and explanations, and puts the staff of knowledge directly into the hands of the amateur and sets him at work. —The Press, Promdence, B. I. ... People who have money to spend in adorning their grounds, are told here how to do it to the best advantage, and ladies are fully instructed in all the art and mystery of window-gardening. It will prove a useful guide to all who have a taste for flowers, and also contains practical instructions for the cultivation of fruits and vegetables.— !%« Transcript, PorUand, Me. This volume is eminently clear in its style and practical in its direc- tions. Its appearance is timely, as it contains some valuable hints upon winter flowering plants and their proper cultivation, together with plain directions how to raise them from seed and to multiply them by cuttings.— Courier-Journal, Louisville, Ey. Price, post-paid, $1.50. O. JUDD CO., DAVID W. JUDD, Pres't. SAM'L BURNHAM, Sec. 7S1 BROADWAY, NEW IfOKK. Gardening for Young and Old. THE CULTIVATION OF SARDEN VEGETABLES IN THE FARM GARDEN. By JOSEPH HARRIS, M.S., Lutkor Of "Walks and Talks on, the Farm,''' "Harrison the Pig,'' "Talks on Manures,"" eta CONTENTS. Introduction.— An Old and a New Garden.— Gardening for BoyB.--How tu Begin.— Preparing the Soil.— Killing the Weeds.- About High Farming.— Com- petition in Crops.— The Manure Question.- The Implements Needed.— Start- ing Plants in the House or in the Hot-hed.— The Wiadow-box.— Making the Hot bed.— Cold Frames.- Insects.— Tlie Use of Poisons.^. The Care of Poisons, —The CultiTation of Vegetables in the Farm Garden.— The Cultivation of Flowers. ILLLUSTRATED. ISmo. Cloth. Price, post-paid, $1.25. O. JUDD CO., DAVID W. JUDD, Pres't. SAM'L BURNHAM, Sec. T51 BROADWAY, NEW VORK. \-.