Ol/^ See the testimonials at pages 16,' 17, &c., of ALL, without 
 exception, of the ship-builders in the city of New York — the best naval 
 architects in the world — and the only place where this dock and the 
 Balance dock are in operation together — preferring this plan to THAT 
 and ALL OTHERS jtKtls'o the concurrence of all the rest of the ship- 
 ping interest of that city. 
 
 O c-X^AD c r--C>t5"t tr^to <~-&\Q oU^O & 
 
 i E 
 
 B R I r F S KETCH 
 
 OF THE 
 
 PLAN AND ADVANTAGES 
 
 OF 
 
 AN IMPROVED STONE DRY DOCK 
 
 COMBINED WITH 
 
 A SECTIONAL 
 
 I FLOATING DRY DOCK 
 
 k 
 I 
 
 §11 
 
 m 
 
 QAwmPC 
 I 
 
 jgB2 LEVEL BEDWAYSj SLIDING WAYS, AND HOUSED SLIPS 
 FOR REPAIRING, LAUNCHING, AND LAYING 
 UP IN ORDINARY, THE SHIPS OF THE 
 
 AND FORMING 
 
 A P E R M A N E N T 
 STONE BASIX, PLATFORM, 
 
 m 
 
 I 
 
 5 
 
 G 5 ' 
 
 : .5. 
 
 i 
 
 : a ^ 
 
 UNITED STATES NAVY, 
 
 NEW-YORK: 
 PRINTED P>Y P. MILLER, NO. 102 BROADWAY 
 NEAR WALL STREET. 
 
 llli!!ii|MiiUMniaii"«" 
 
 1845. 
 
 1 
 
 I 
 
TftYlOR 
 JTM. COLti 
 
 I.Uer.F 
 
A 
 
 BRIEF SKETCH 
 
 OF THE 
 
 PLAN AND ADVANTAGES 
 
 OF A 
 
 SECTIONAL FLOATING DRY DOCK, 
 
 CO M BIN ED WITH 
 
 A PERMANENT STONE BASIN AND PLATFORM, 
 
 AND CONNECTED WITH 
 
 LEVEL BEDWAYS, SLIDING WAYS, AND HOUSED SLIPS, FOR 
 REPAIRING, LAUNCHING, AND LAYING UP IN 
 ORDINARY, THE SHIPS OF THE 
 
 UNITED STATES NAVY. 
 
 NEW-YORK: 
 
 PRINTED BY P. MILLER, 102 BROADWAY, NEAR WALL STREET. 
 
 1845. 
 
Avery Architectural and Fine Arts Library 
 Gift of Seymour B. Durst Old York Library 
 
OVOkkS (bo 
 
EXPLANATION OF THE PLATE. 
 
 A. A. Represents a part of the Navy Yard. 
 
 B. The Face Wall or Bulk Head of Navy Yard. 
 
 C. A Pier extending out at right angles 175 feet. 
 
 D. The Stone Basin and Platform 250 feet square. 
 
 E. is the Sectional Dock with a ship elevated on it. 
 
 F. F. F. is three Sett Ways on three sides of the Basin. 
 
 G. is a Hydraulic Cylinder for drawing off a ship. 
 
 H. A Ship House covering three sett ways. 
 
 I. A ship drawn off the Docks on the ways. 
 
 J. is the Keel of a new ship laid on the ways for building. 
 
Digitized by the Internet Archive 
 in 2013 
 
 http://archive.org/details/briefsketchofplaOOdaki 
 
SECTIONAL FLOATING DRY DOCK. 
 
 The Sectional Floating Dry Dock is a recent invention, 
 for which several Patents have been issued. It has been 
 in operation about five years in the City of New York, and 
 has acquired the entire confidence of every Shipbuilder, 
 Shipwright, and all persons engaged in Shipping or Steam 
 Boats, who have had occasion to make use of it, and near- 
 ly all of whom have voluntarily come forward and signed 
 certificates declaring its decided and unquestioned superi- 
 ority over all other plans of Docks. During the time it 
 has been in operation, about 1600 vessels, Ships and Steam 
 Boats, have been raised and repaired upon it without the 
 slightest accident either to the vessel or Dock, and it has 
 given universal satisfaction both to the owners and ship- 
 wrights. Among the ships raised, have been the Steam- 
 ship Great Britain, the largest Steamer in the world and 
 of tonnage greater than a Ship of the Line, the Mexican 
 War Steamers Montezuma and Gaudaloupe, the merchant 
 ships Henry Clay, Queen of the West, John R. Skiddy, 
 Ackbar, Thos. W. Perkins, Iowa, Queen Victoria, U. S. 
 Sloop of War Vincennes, and numerous other first class 
 ships, also the Steam Boats, Natchez, Diamond, Albany, 
 North America, South America, Rhode Island, De Witt 
 Clinton, Utica, Mohegan, Knickerbocker, Troy, Massa- 
 chusetts and many others, all with the most perfect ease, 
 safety and satisfaction to their owners. 
 
 A recent improvement has been made in the manner 
 of using this Dock by uniting or combining it with a per- 
 
6 
 
 manent Stone Basin, connected with Bed and Sliding 
 Ways with a view of adapting it to the service of the Na- 
 vy, for the purpose of repairing, rebuilding or laying up 
 in ordinary, vessels of War, which in the opinion of Me- 
 chanics and Engineers competent to judge, renders it su- 
 perijr and much more efficient and convenient than the 
 excavated Stone Dock, or any other plan known. The 
 mode of using the Dock will be hereafter explained. 
 
 In Great Britain the want of some such plan for raising 
 Ships and laying them up in ordinary, in Ship houses a- 
 bove the level of the water, has long been felt and ac- 
 knowledged. 
 
 In order to provide for the protection of large ships, a 
 great number of Granite Dry Docks have been built, at 
 an enormous expense, (though much less than they would 
 have cost in this country, owing to the great rise and fall 
 of the tide there,) and such of them as are not required 
 for building and repairs, are covered with roofs and used 
 for laying up some of the ships-of-the-line, that are in or- 
 dinary, though the number is, as yet inadequate to pro- 
 vide except for a small portion of them. The importance 
 which is attached to this subject in that country, whose 
 experience in naval matters, will be conceded by all to 
 be worthy of profound consideration, is evinced by the 
 following extracts from the Encyclopedia Britannica, vol. 
 8, pp. 77, &c. 
 
 " Another very material improvement, recently introduced into His Majesty's 
 Dock Yards, is that of covering the Dry Docks and Building Slips with roofs. 
 The rapid decay of our ships of war, by that species of disease known by the 
 name of dry rot, attracted very general attention; its effects were well known, but 
 a variety of opinions were entertained as to its causes and its cure. It was quite 
 obvious, however, that exclusion of air and moisture, were the two great operating 
 causes in giving activity to the progress of the disease, and that a ship in dock 
 stripped of her planking, and open to the weather in every part, alternately exposed 
 to frost, rain, wind and sunshine, must at least have her timbers differently affec- 
 ted, some swelled and water soaked, and others shrunk with heat, and others rif- 
 ted with wind and frost; and if closed up with planking in this state, might be ex- 
 pected at no great distance of time, to exhibit symtoms of decay. The workmen, 
 too, in the open Docks and Slips, suffered from the vicissitudes ofth§ weather, no 
 
7 
 
 less than the ships, and their labor was frequently suspended, to the great detri- 
 ment of the naval service. The measure of roofing over the Docks and Slips, had 
 long and repeatedly been suggested, but, either from prejudice or false economy, 
 it was only very recently carried into practice, and is now almost universal in all 
 the Yards. " 
 
 Again: " These covers have been in use in Venice, from time immemorial, and 
 Mr. Strange, the British Consul at that port, in 1792 says, that he saw twenty-two 
 large ships laid up there under covered Slips, some of which had lain there for 
 sixty years. " 
 
 Again : " The advantages which Slips are supposed to possess over Dry Docks, are 
 many and important. They can be constructed at one twentieth part of the ex- 
 pense; they occupy less space; they can be constructed on a steep or a shelving 
 shore, and ships can be hauled upon them either in spring or neap tides; whereas 
 a Dry Dock can only be made in particular situations, and when made, ships can 
 only be docked and undocked, in certain states of the tides, from which circum- 
 stance considerable delay and inconvenience are frequently experienced. It 
 should be recollected, however, that a large ship must necessarily go into a Dock 
 preparatory to her being hauled out in the Slip. It has been considered not at all 
 improbable, as was suggested sometime ago by Mr. Perring, that the whole Ordi- 
 nary may hereafter be laid on Slips, which, if housed over, would unquestionably be 
 the best means of increasing their durability, and preserving them from partial decay. 
 Nor is it certain that in the end, it would not be the most economical. " 
 
 It will be seen that it is fully admitted in England, that 
 many serious objections exist against the present system 
 of Excavated Docks which were constructed at a time 
 when no other method was known for taking ships out of 
 the water. These defects we now propose to remedy in 
 a great measure by the introduction of a new plan of 
 Dock, Basin, Bed and Sliding Ways. 
 
 Similar views were entertained by President Jefferson, 
 who in his Message to Congress, in December, 1802, says : 
 " Presuming it will be deemed expedient to expend an- 
 nually a convenient sum toward improving the Naval 
 defence, which our situation may require, I cannot but 
 recommend that the first appropriations for that purpose, 
 may go to the saving of what we already possess. No care, 
 no attention, can preserve vessels from rapid decay, which 
 lie in water and exposed to the sun. These decays require 
 great and constant repairs, and will consume, if continu- 
 ed, a great portion of the moneys destined to Naval pur- 
 poses. To avoid this waste of our resources, it is pro- 
 posed to add to our Navy Yard here, a Dock, within 
 
8 
 
 which our present vessels may be laid up dry and under 
 cover from the sun. Under these circumstances , experience 
 proves that icorks of wood will remain scarcely at all affec- 
 ted by time. Similar depositories for laying up, as well 
 as building and repairing vessels, may hereafter be under- 
 taken at other Navy Yards." 
 
 The method of raising the ships to the requisite eleva- 
 tion, for protection in housed slips, on an inclined plane, 
 in addition to the difficulty of applying the requisite 
 mechanical force to accomplish it, is liable to the still 
 more serious objection, that when they are to be let into 
 the water again, they must be launched in the ordinary 
 way. The evils and dangers attendant upon launching, 
 are so serious, that ships of the first class are commonly 
 constructed at present in Dry Docks, in England, and af- 
 terwards floated out by opening the flood gates* In this 
 country, the Board of Navy Commissioners have taken 
 the same view of the subject, and recognised the injuries 
 which result from launching ships of the first magni- 
 tude.! 
 
 It will therefore at once be admitted, that a plan, which 
 will raise vessels from their floating level, wholly above 
 the surface of the water, and deliver them upon the sur- 
 face of the dry land, and which, with an efficiency almost 
 unlimited, can raise one ship after another, till it delivers 
 a whole fleet upon the shore, and is, at the same time, 
 cheaper in its construction, more convenient, and better 
 in its operation than any other known method, will ren- 
 der services to the naval marine of the highest impor- 
 tance, by preserving the maratime power of the nation in 
 a state of efficiency, ready for active use, and saving con- 
 tinual outlays for the building of new ships to take the 
 place of those that decay. 
 
 Such a plan is provided by the SECTIONAL FLOAT- 
 
 * Vide Encyc. Brit., vol. 13, p. 55. t U. S. Navy Com. Report, to 19th Con- 
 gress, (1826.) 
 
4 
 
 9 
 
 ING DRY DOCK, used in connection with its perma- 
 nent Platform, Basin, Bed ways, and Housed Slips. It 
 can be built with all its appurtenances, in one fifth part 
 of the time usually required in erecting one stone dock, 
 and at much less expense, and in point of efficiency for 
 actual use, it is equivalent to a number of Stone Docks. 
 Indeed, it may be said witli truth, that one Dock upon 
 this plan, is superior in all its respects to the whole com- 
 bined system of English, Dry Docks, for their naval estab- 
 lishment, which lias cost them many millions of dollars. 
 
 It is unnecessary to give a written description of the 
 Dock and working model, as the accompanying plan will 
 explain its operation. It should however be stated, that 
 the Dock is lowered, the ship to be raised is floated over 
 the keel blocks, and the water is exhausted out of the 
 Dock, which rises or floats above the level of the w 7 ater 
 with the ship upon it. 
 
 Having supposed the vessel elevated entirely above the 
 surface of the water, upon a floating structure, which will 
 draw about ten feet of water when thus raised, and 
 capable of being easily moved with its burden in any 
 required direction, let the reader imagine a basin large 
 enough to turn the Dock around within it, excavated in 
 the shore contiguous, with a permanent level platform of 
 piles, concrete or masonry, constructed in its bottom, al- 
 lowing the water to flow over it a sufficient depth, say 
 ten feet. It will readily be perceived, that the Dock, 
 with the vessel on it, may be floated into the basin, and 
 allowed, by filling the tanks with w 7 ater, to settle and 
 rest upon the platform, whfch will afford a stable and per- 
 manent foundation, to sustain it beyond the reach of ac- 
 cidents. Let him suppose that a number of level bedways 
 are laid upon the shore at right angles to any of the three 
 sides of this basin; that the Dock, with the vessel on it, 
 being easily turned around in the water, is made to settle 
 2 
 
10 
 
 down in the direction of, and in connexion with, any one 
 of these bedways, at the option of the superintendent ; that 
 the bed way selected, is extended from the shore upon the 
 top of the Dock, directly under the ship; that a cradle is 
 made under the ship's bottom, to which sliding ways 
 are firmly attached ; and that, by a mechanical power 
 fixed upon the shore, or in any convenient manner, the 
 vessel is hauled off from the Dock on a level, by the cra- 
 dle, into a ship house on the solid earth, from which it 
 may be delivered back again upon the Dock, at pleasure. 
 The reader will then understand how one vessel after an- 
 other, being first raised on the Sectional Floating Dock, 
 is delivered arid carried out upon the surface of the earth, 
 or removed back again upon the top of the Dock, to be 
 let down into the water. 
 
 In addition to the number of ships that could thus be 
 delivered on the ways, at the same time, the Dock would 
 be at liberty to raise and hold ships requiring temporary 
 repairs, and is alone, independent of its connexion with 
 the basin, platform, and bedways, far more efficient than 
 a Stone Dock, as it can take two or more vessels upon it 
 at the same time. 
 
 A more efficient, perfect, safe and easy manner of de- 
 livering ships out of the water can scarcely be conceived, 
 and it is allowed by all practical mechanics, (whose ex- 
 perience gives their judgements a weight, which that of 
 the mere theorist is not entitled to,) to be the best, most 
 convenient and cheapest method ever before devised; ob- 
 viating all the objections against both Floating and Stone 
 Docks, combining the convenience of the light, flexibility, 
 air, and room of the one, with the permanency and solidity 
 of the other, and presenting a facility and efficiency for 
 taking out a number of ships at the same time, and safely 
 launching large ships or steamers, peculiar to itself alone, 
 and hitherto wholly unknown. 
 
11 
 
 By the aid of this Dock, not one ship alone, as in a 
 Stone Dock, but a whole fleet, could, one after another 
 at a small expense, be securely placed upon the stocks in 
 a Navy Yard, or laid up in ordinary in ship houses where 
 they would be perfectly protected against dry rot and eve- 
 ry other source of decay. By its aid, the longest steam- 
 ers and the heaviest ships of the line, could be safely 
 launched without incurring the risk of straining, or hog- 
 ging, or wrinkling their copper, while in Great Britain, 
 vessels of this kind are usually constructed in Stone Docks 
 to avoid this serious evil. 
 
 It is claimed that this plan of Dry Dock, is greatly su- 
 perior to the Excavated Stone Dock and any other Dock 
 whatever, for the following among other reasons, viz: 
 
 1. It presents a pliant, flexible, and yielding platform, 
 capable of being made of any required strength by trus- 
 sing, which conforms as soon as the vessel is brought to 
 its bearing, to the shape of the keel and bottom; being 
 upheld itself by the upw ard pressure of the water, more 
 or less power being applied by each section, as required 
 by the displacement of the ship. 
 
 2. It brings the vessel's bottom up fully into the light 
 and air and affords a clear, broad, and well lighted plat- 
 form from stem to stern, enabling the w r orkmen to do 
 their work from fifteen to tw T enty per cent, cheaper than 
 on any other dock. 
 
 3. It is capable of extension, contraction, and division, 
 adapting itself to the length of the vessel, and forming on 
 the instant, two or more separate docks, each indepen- 
 dent and perfect in itself; so that putting all the sections 
 together, it is capable of raising the largest ship-of-the-line, 
 or separating them into two or more berths, it can at the 
 same time, take up tw T o vessels of a smaller class, as a 
 frigate and sloop-of-war; an advantage, which is of much 
 moment when it is considered that the greatest portion of 
 
12 
 
 vessels in the Navy are of the latter class, and which ren- 
 ders a Dock of this kind equal to two on any other plan ; 
 and when used in connexion with hed and sliding ways, 
 its efficiency is increased immensely, and can he carried 
 to any desired extent. 
 
 4. It is easily taken out of the water to he repaired, 
 one section beii.g raised on two others for that purpose; 
 but other floating docks, though much more liable to get 
 out of repair, in consequence of t he immense strain on an 
 inflexible platform, cannot be repaired without great diffi- 
 culty even on a small scale, and not at all on a large one. 
 
 5. A Dock on this plan can be towed together or in 
 sections from place to place, at a trifling cost, and in case 
 of danger from the enemy, it could be sunk in deep wa- 
 ter or removed to a { lace of safety, and after the danger 
 is over, it could be raised and returned to its pjsition. 
 
 6. The best test of the simplicity of all the machinery 
 which has been devised and applied to obtain the above 
 important results^ is to be found in the fact, attested by 
 the certificate of the Superintendent, who has worked the 
 Dock ever since it was built, that no accident of any kind 
 has ever occurred, either to the Dock or to any vessel, nor 
 has the slightest injury happened to any part of the ma- 
 chinery. 
 
 On this Dock a ship is raised on a large, tight, dry 
 platform above the level of the water, and held in exactly 
 the same position as when afloat, in the most firm and 
 secure manner, and presents, (in the language of an intel- 
 ligent shipbuilder,) a most perfect una 1 convenient Ship 
 Yard afloat. Every part of a ship can be thoroughly ex- 
 amined, and lays as convenient for the mechanic to make 
 his repairs, as if she was on the stocks in a ship yard, and 
 it is admitted by shipwrights, that a ship can, from the 
 convenient manner in which she lays, be repaired at least 
 15 or 20 per cent, less than in any other plan of Floating 
 
13 
 
 or Dry Dock. It will readily be perceived that, in an 
 Excavated Dock, the ship i 
 
 surface, in a very ine mveriient p i uechanic 
 has to make his repairs in a dajk, datnp, unwholesome 
 place. As evidence of the convenience of this Dock, and 
 the great facility and despatch it affords for raising, 
 working and making repairs on ships, one simple fact 
 may here he stated. 
 
 The steamboat Knickerbocker, one of the longest in 
 the world, being 306 feet in length, and 1000 tons burden, 
 was raised, cleaned, and let down by this Dock, in seven 
 hours, a despatch in docking unprecedented in this or any 
 other country. Previous to raising this boat, a line of 
 sights was placed across the deck, about ten feet apart 
 from stem to stern, which has also been done with other 
 long boats raised, and without, in any instance, being 
 changed from a straight line in raising or lowering the 
 boats and every door would open and shut without bind- 
 ing as freely as when the boat was afloat in the water, 
 this is accomplished by exhausting more water from one 
 than another section, to correspond with the displace- 
 ment of the boat w T hen afloat. 
 
 From two to three days is the usual time required for 
 raising, stripping, caulking, recoppering and lowering in- 
 to the water packet ships of the first class, a despatch 
 attained by the short time required in Docking the Ship, 
 and the facilities afforded the workmen. 
 
 It is presumed that the memorials and certificates an- 
 nexed hereto, signed by every shipbuilder and all the ship- 
 wrights in the city of New- York, but two, (who are in- 
 terested in other docks.) and by distinguished houses in- 
 terested in shipping, together with the certificates of own- 
 ers of steamboats and eminent civil engineers, will be 
 sufficient 1o satisfy any unprejudiced and candid mind of 
 the great superiority and utility of this Dock, and its pre- 
 
14 
 
 eminent claims upon the attention of Congress. They 
 are signed by men whose names, as eminent and skilful 
 shipwrights, will be recognised by all with respect and 
 pride. Among those who have signed the recommenda- 
 tions are Messrs. Westervelt & Mackey, the builders 
 of the splendid Havre packets, and more lately of those 
 models of beauty and skill, the Ashburton, Princi Albert, 
 and Victoria ; Messrs. Brown & Bell, known as the 
 builders of the celebrated London packets, the Spanish 
 Steamers, and Queen of the West; Messrs. Webb & Al- 
 len, builders of the wel l known Liverpool packets ; 
 Messrs. Smith & Dimon, builders of the splendid Knick- 
 erbocker steamboat, and a number of merchant ships ; 
 Messrs. Bishop & Simonson, also, Jabez Williams, well 
 known as extensive and skilful shipbuilders ; William 
 H. Brown, well known as the builder of the Russian 
 steamer, Kamschatka, and the Empire; Divine Burtis, 
 builder of some of the North River steamboats ; and Her- 
 bert Lawrence, well known as the builder of a large num- 
 ber of L. I. Sound steamboats. Messrs. Whitlock & 
 Berrien, Webb, Robertson & Co., and Bucknam & Casi- 
 laer, are well known as very extensive shipwrights and 
 of great practical experience in raising ships, and work- 
 ing upon all kinds of docks, The well known names of 
 Jas. A. Stevens, Esq., Cornelius Vanderbilt, Esq., and J. 
 Newton, Esq., will also be recognised as large steamboat 
 owners, and men of great practical knowledge, and who 
 have had a number of the largest class of steamers repair- 
 ed upon this Dock. The opinion of all these experienced 
 and practical shipbuilders and shipwrights, is entitled to 
 great weight, and their character as such would not suf- 
 fer by a comparison with that of any other class of naval 
 architects, in this or any other country. 
 
 By the annexed certificates, it will be seen that most 
 of the foregoing facts are strongly substantiated by a class 
 
15 
 
 of men, who will at once be admitted to be the best judges 
 of the subject, viz : the shipbuilders, shipwrights, and 
 owners of ships anil steamboats, who are thorough prac- 
 tical mechanics, or have a deep interest in the subject, 
 and who have seen, tried, and thoroughly proved and test- 
 ed this Dock, and who have been conversant with it from 
 the time the first section was launched in 1840. As all 
 the shipbuilders, shipwrights, and most of the shipown- 
 ers in New- York have signed the certificates, it cannot be 
 attributed to party influence or favour, but is a voluntary 
 and significant tribute to the vast superiority of this Dock, 
 by the whole shipping interest of New-York. 
 
 A statement is annexed in the appendix exhibiting the 
 saving to the Government, by constructing a floating in- 
 stead of a Stone Dock, and showing that economy is 
 united with great improvement, and cheapness with su- 
 perior merit. 
 
A P P E N D I X. 
 
 (A.) 
 
 List of shipbuilders in ths City of New-York, engaged in business at 
 the present time : 
 
 WESTER VELT & MACKEY, 
 HERBERT LAWRENCE, 
 JABEZ WILLIAMS, 
 BROWN & HELL, 
 WEBB & ALLEN, 
 SMITH & DEMON, 
 BISHOP & SIMONSON, 
 DIVINE BURTIS & CO., 
 WILLIAM H. BROWN. 
 
 List of shipwrights in the City of New-York, engaged in business at 
 the present time : 
 
 WEBB, ROBERTSON, & CO., 
 BUCK NAM & CASILAER, 
 WHITLOCK & BERRIEN, 
 IRVINE & CLARK, 
 PETER MACNAMARA, 
 FRANCIS SECOR & CO., 
 
 We hereby certify, that the above are lists of leading and principal 
 shipwrights and shipbuilders, engaged in business in the city of New- 
 York at the present time. 
 
 (Signed) GRINNELL, MINTURN, & CO. 
 
 The above list is introduced to show, that all the principal shipbuilders 
 and shipwrights have signed certificates in favour of the Dock, and pre- 
 ferring it to any other plan of a dock. 
 
 (B-) 
 
 To the Senate and House of Representatives of the United States, in 
 
 Congress assembled. 
 
 The memorial of the undersigned shipbuilders and shipwrights, resi- 
 dent and in business in the City of New-York, respectfully represents : 
 that your memorialists are well acquainted with the several plans of Dry 
 Docks for raising vessels for coppering and repairs : that among the se- 
 veral establishments for this purpose, at present in operation in this City, 
 the one known as the Sectional Floating Dry Dock, at the foot of Rut- 
 gers-street, possesses by far the greatest elevating capacity : that we have 
 repeatedly had vessels repaired upon it to our entire satisfaction : that we 
 have no hesitation in declaring it in every respect a superior Dock, and 
 most admirably adapted to accomplish the object for which it was con- 
 structed : that merchant ships of the largest class, have been raised upon 
 
17 
 
 it in the most satisfactory manner, and that vvc entertain no doubt that the 
 elevating power of this kind of Dock can be extended with perfect safety 
 to a capacity of raising a line-of-battle ship : that its sectional arrange- 
 ment gives the structure the ability to be extended to accommodate the 
 largest steamers, and embrace their greatest width without endangering 
 its strength, and from its flexible platform, enables it to conform to the 
 shape of the vessel, and lift it equally upon its bottom, and endues it with 
 the important advantage of being divisible into two separate Docks, to 
 raise two vessels at a time, and perform the service of two independent 
 Docks on any other p an : anc 1 that on these accounts and others, we 
 prefer it to the plan of any other Floating Dock known to us. We, 
 therefore, cheerfully recommend it to the Government, as a useful Dock 
 fur the service of the Navy ; and your memorialists, as in duty bound, 
 will ever pray, &c. 
 
 New-Yoiik, January 2, 1543. 
 
 WEBB, ROBERTSON, & CO., Shipwrights. 
 
 C. & R. POILLON, do. 
 
 BUCKNAM & CASILEAR, do. 
 
 JNO. HARRISON, do. 
 
 WESTER VELT & MACKEY, Shipbuilders. 
 
 HERBERT LAWRENCE, do. 
 
 WHITLOCK & BERRIEN, Shipwrights. 
 
 DIVINE BURTIS & CO., Shipwrights and builders, 
 
 BROWN & BELL, Shipbuilders. 
 
 WEBB & ALLEN, do. 
 
 WM. H. BROWN, do. 
 
 DEINIKE & KING, Shipwrights and sparmakers. 
 
 BAYLES & BROWN, do. do. 
 
 BISHOP & SIMONSON, Shipbuilders. 
 
 IRWIN & CLARK, Shipwrights and builders.. 
 
 W3I. RODMAN, Shipwright. 
 
 C. EDGAR SMITH, Shipwright. 
 
 GEO. A. SAUNDERS, do. 
 
 ALLEN GORHAM, do. 
 
 FICKET & THOMAS, Shipbuilders, 
 
 (C.) 
 
 To the Senate and House of Representatives of the United States,. 
 
 The Memorial of the undersigned, ship owners and interested in 
 shipping, resident and in business in the City of New-York, respect- 
 fully represents : That your memorialists are well acquainted with 
 the several plans of Dry Docks, for raising vessels for coppering and re- 
 pairs : that among the several establishments for this purpose, at present 
 in operation in this City, the one known as the Sectional Floating Dry 
 Dock, foot of Rutgers-street, E. R., possesses by far the greatest eleva- 
 ting capacity : that we have no hesitation in declaring it in every respect 
 a superior Dock, and most admirably adapted to accomplish the object 
 for which it was constructed : that merchant ships of the largest class 
 
 3. '• 
 
18 
 
 have been raised upon it in the most satisfactory manner, and that we 
 entertain no doubt that the elevating power of this kind of Dock, can be 
 extended with perfect safety to a capacity of raising a line-of battle ship : 
 that it raises the vessel up more fully into the light and air, and affords 
 the shipwright more room and better access to the vessel's bottom, than 
 any other Dock ; that its sectional arrangement gives the structure the 
 ability to be extended to accommodate the longest steamers, and em- 
 brace their greatest width, without endangering its strength; and from 
 its flexible platform, enables it to conform to the shape of the vessel and 
 lift equally upon its bottom, and endues it with the important advantage 
 of being divisible into two separate Docks, to raise two vessels at a time, 
 and perform the service of two separate Docks on an) other plan : that 
 on these accounts and others, we prefer it to any other plan of Dry Dock 
 that has come to our knowledge. We, therefore, ch<erfully recommend 
 it to the Government as a useful Dock for the service of the Navy, and 
 your memorialists will ever pray, &.c. 
 New-York, Dec. 29th, 1842. 
 
 GRINNELL, MINTURN, & CO., Agents and part owners of the 
 new lines of London and Liverpool packet ships. 
 
 CHAS. M. MARSHALL, Agent and part owner of the Old line of 
 Liverpool oackets. 
 
 ROBERT KERMIT, Agent and part owner of the Old lines of Liv- 
 erpool and London packets. 
 
 RICHARD IRVIN, Agent and part owner of the Great Western line 
 of Atlantic steamers. 
 
 DUNHAM & DIMON, Agents and part owners of the New Orleans, 
 Mobile and Charleston packets. 
 
 C. BOLTON, FOX, & LIVINGSTON, Agents and part owners 
 of the Havre line of packet ships. 
 
 BARCLAY & LIVINGSTON, Agents of the Cunard line of At- 
 lantic steamers. 
 
 GOODHUE & CO., Agents and part owners of the Old line Liver- 
 pool packets. 
 
 JOHN GRISWOLD, Agent and part owner of the London Old line 
 of packets. 
 
 WOODHULL & MINTURN, Agents of the Liverpool line. 
 
 JOHN ELVVELL & CO., Agents and part owners of the Mobile 
 and New Orleans packets. 
 
 STURGES & CLEARMAN, Agents and part owners of the Sa- 
 vannah, Norfolk, and Mobile packets. 
 
 JOHN OGDEN, Agent and part owner of the Richmond and other 
 Southern packets. 
 
 POST & PHILLIPS, Agents and part owners of the Apalachicola 
 and other packets. 
 
 CENTER & CO., Agents and owners of Mobile packets. 
 
 JOHNSON & LOWDEN, Agents and owners of New Orleans 
 packets. 
 
 SAMUEL THOMPSON, Agent and owner of Liverpool packets. 
 ABRAHAM BELL & CO., Agents of Transatlantic Steam Navi- 
 gation CO. 
 
19 
 
 ROCHE, BROTHERS. & CO., Agents of Liverpool packets. 
 JACOB HARVEY, President of Washington Marine Insurance Co. 
 Z. COOK, Jr., President Mutual Safety Insurance Company. 
 
 GORDON & TALBOT, Shipowners. 
 
 TAYLOR & MERRILL, do. 
 
 S. E. GLOVER, do. 
 
 WM. M. PECK, do. 
 
 TALBOT, OLYPHANT. & CO., do. 
 
 CARY & CO., do. 
 
 BUCK & CO., do. 
 
 JOSIAH MACY & SONS. do. 
 
 H. & J. B. MURRAY, do. 
 
 A. G. & A. W. BENSON, do. 
 PETER J. NEVIUS & SONS, do. 
 DAVIS, BROOKS, & CO., do. 
 JOHN B. LAS A LA & CO., do. 
 J. FOULKE & SONS, do. 
 HICKS & CO., do. 
 E. DUNSCOMB & BECKWITH, do. 
 JOHN PETERS & CO., do. 
 ALLEN & PAXON, do. 
 MOSES TAYLOR, do. 
 PRATT & BURR, do. 
 JONATHAN HILLMAN, do. 
 P. J. FARNHAM & CO., do. 
 SLATE, GARDNER, & HOWLAND, do. 
 J. & N. BRIGGS, do. 
 DEPEYSTER & WHITMARSH, do. 
 NEVY YORK INSURANCE COMPANY, 
 AMERICAN INSURANCE COMPANY, 
 
 B. McEVERS, Ship owner. 
 A. B. NEILSON, do. 
 HOWES, GODFREY, & ROBINSON, do. 
 PETER HARMONY'S NEPHEWS, do. 
 
 R. P. BUCK, do. 
 
 JAMES HENRY, do. 
 
 RUSSELL & COPELAND, do. 
 
 EVERETT & BATTELIE, do. 
 
 BRETT & VOSE, do. 
 
 AND MANY OTHERS. 
 
 (D.) 
 
 I hereby certify, that I had the large packet ship, "Ville de Lyon," ta- 
 ken out a short time since, on five of the seven sections of the Floating 
 Dry Dock, foot of Rutgers street, E R., in a manner perfectly satisfac- 
 tory. She was raised with great facility, without the least strain, the 
 Dock conforming to the shape of the vessel, and lifting equally on all its 
 parts, and was held in a perfectly easy manner while out of the water; re- 
 maining on during one of the severest storms experienced in this harbor, 
 without the least strain or motion of the vessel or Dock ; and I have no 
 
20 
 
 hesitation in recommending ibis as a perfectly safe Dock; possessing the 
 greatest elevating power within my knowledge, and affording greater faci- 
 lities for making the repairs, having a broad, tijjjit floor from stem to 
 stern, unobstructed light and free access to the bottom of the vessel. 
 
 CHARLES S 101) DART, 
 
 New- York,- Dec. 24, 1842. Master of the Ville de Lyon. 
 
 We concur in the above statement of Captain Stod'dart. 
 
 C. BOLTON, FOX, & LIVINGSTON, 
 Owners of the Ville de Lyon and Agents of the Havre packets. 
 December 30, 1S42. 
 
 (E.) 
 
 New-York, Oct. 24, 1S42. 
 
 The undersigned, interested in steamboats, and resident in the City of 
 New- York, do hereby certify, that we are acquainted with the operation 
 of the Sectional Floating Dry Dock, at the foot of Rutgers-street, in the 
 East River ; that we have had steamboats repaired thereon ; that we un- 
 hesitatingly pronounce it the best plan of Dry Dock, that we know of, 
 for taking up steamboats for repairs, and as such, we recommend it to 
 the attention of the Navy Department, to be adopted for the use of the 
 United States Navy. 
 
 JAMES A. STEYExVS, 
 
 S. R. ROE, 
 
 R. B. COLEMAN, 
 
 A. H. SHULTZ, 
 
 ALEX'R McLEAN, 
 
 DANIEL DREW, 
 
 J. H. VANDERBILT, 
 
 JOSEPH J. COMSTOCK, 
 
 CORNELIUS VANDERBILT, 
 M. H. TRUESDELL, 
 L. U. BRAINARD, 
 J. NEWTON, 
 JOHN B. VAIL, 
 CURTIS PECK, 
 JOHN DUNLOP, 
 ANTHONY N. HOFFMAN. 
 
 (F.) 
 
 We, the undersigned, shipwrights, &c, resident and in business in 
 the City of New-York, do hereby certify, that we have been for a long 
 time engaged in the business of coppering and repairing vessels, and 
 are well acquainted with the different plans of Dry Docks, used for that 
 purpose ; that we are familar with the construction and operation of the 
 Sectional Floating Dry D<ck, foot of Rutgers-street, East River, and 
 we have no hesitation in declaring it, in our opinion, the best plan of 
 Dry Dock known to us ; that the conveniences for shoring and staging; 
 the broad tight floor from stem to stern ; the perfect exposure of the ves- 
 sel's bottom to the light and air; and the facilities for repairing or put- 
 ting on a keel or shoe, by depressing into the water by means of screws, 
 one section at a time, and giving the vessel an equally easy bearing on 
 continuous ways on each side of the keel, which is left clear of the blocks 
 
21 
 
 the entire length of the vessel, if necessary, enable the workmen to ac- 
 complish their labor from 15 to 21) per cent, cheaper in this than any 
 Dry Duck, on any other plan. 
 
 WEBB, ROBERTSON, & CO., Shipwrights. 
 DIVINE BURTIS & CO., Shipwrights and builders. 
 BUCKNAM & C A SI LEAR, Shipwrights. 
 IRVIN & CLARK, Shipwrights, caulkers, &c. 
 WESTER VELT & MAC KEY, Shipbuilders, &c. 
 WHITLOCK & BERRIEN, Shipwrights. 
 WEBB & ALLEN, Shipbuilders. 
 BISHOP & SIMONSON, Shipbuilders. 
 BROWN & BELL, Shipbuilders. 
 DENIKE & KING, Shipwrights. 
 GEORGE A. SAUNDERS, Shipwright. 
 HERBERT LAWRENCE, Shipbuilder. 
 BAYLES & BROWN, Shipwrights. 
 C. & R. POILLON, Shipwrights. 
 JOHN HARRISON, Shipwright. 
 C. EDGAR SMITH, Shipwright. 
 ALLEN GORHAM, Shipwright. 
 
 New-Y'ork. Jan. 4, 1843. 
 
 (G.) 
 
 LETTER FROM CAPTAIN GREGORY, U. S. NAVY. 
 
 U. S. Rec. Ship, North Carolina. 
 
 New- York, Nov. 16, 1842. 
 
 Sir — L T nderstanding that S. D. Dakin, Esq., President of the New- 
 York Dry Dock Company, is about presenting himself to you for the 
 purpose of laying before you, plans and proposals for building a Dock 
 upon the same principles, for Naval purposes, upon this station ; I beg 
 leave most respectfully, to represent for your information, that having at 
 various times, since the Floating Dock has been in operation, examined 
 its construction, and witnessed the facility, safety, and despatch with 
 which ships have been taken in and repaired, I am fully convinced of its 
 superiority over all other kinds I have seen: and I have no hesitation in 
 recommending it to your consideration, as being, in my opinion, the 
 most safe, economical, and expeditious mode of constructing a Dry 
 Dock ; and that it can be constructed, so as to answer all the purposes 
 required in a JVaval PLstablishment. 
 
 I have the honor to be, 
 
 Very respectfully, your ob't serv't, 
 
 (Signed,) F. H. GREGORY, Captain, U. S. N. 
 
 Hon. A. P. Upshur, 
 
 Secretary of the Navy, Washington. 
 
22 
 
 (H.) 
 
 I hereby certify that I have been the Superintendent of the Sectional 
 Floating Dry Dock since it was first put in operation, in December, 
 1840 ; that since that time, it has been in constant and successful opera- 
 tion, raising vessels of various sizes, from the smallest to the largest; 
 that upwards of 150U vessels have been taken up and repaired thereon, 
 between that time and December, 1845, (about five years) ; that no 
 accident of any kind has ever occurred, either to the Dock itself or to 
 any vessel while being raised or repaired thereon, or let down into the 
 water ; nor has the slightest injury ever happened to any part of the ma- 
 chinery of the Dock. PHINEAS BURGESS, 
 
 Superintendent of the Sectional Floating Dry Dock. 
 
 New-York, Dec. 1, 1845. 
 
 (10 
 
 OPINION OF THE AMERICAN INSTITUTE. 
 
 The American Institute last Spring apnointed a Committee to examine 
 this plan of Dry Dock, who made a long and able report ; but we have 
 room only for the following extract, which embraces the conclusion at 
 which they arrived : 
 
 " In view of the qualities which a Floating Dry Dock possesses, for 
 purposes to which a fixed arrangement would be inapplicable, such as its 
 portability, its easy application in harbours where, from great depth of 
 water or softness of bottom, other Docks could not be constructed, and 
 also from the successful operation of this arrangement, its applicability to 
 the ordinary purposes of a Dry Dock, your Committee feel assured of its 
 extensive adoption, and cheerfully express their opinion of its superiority 
 over any other Floating Dry Dock, or work of this description, which 
 has come to their knowledge. 
 
 June 19, 1842. T. B. STILLMAN, Chairman." 
 
 (J.) 
 
 OPINION OF FOSTER RHODES, Esq., 
 
 Naval Constructor at Brooklyn, and late Chief Naval Constructor to 
 the Grand Seigneur, and builder of the Stone Dry Dock at Con- 
 stantinople, contained in a long and able letter to Mr. Dakin, last 
 Spring, from which the following is a short extract : 
 
 * The structure which you have built, consisting of seven sections, is 
 capable of raising vessels of greater size than any Elevating Dry Dock 
 I have yet seen. This power is, in my opinion, capable of increase to 
 to a very considerable extent, without detriment to its operations, and is 
 exerted in such a manner upon the vessel, as to hold her in position out 
 of the water, by a pressure similar to that which sustains her when afloat, 
 thus affording the best possible security against any strain or injury. 
 
 "In your Dock, the sections fit as it were, to the vessel's keel and 
 bottom, and conform, while they lift, to its floating shape, pressing hard- 
 er or lighter at each point, as it may require more or less support. Many 
 
23 
 
 other advantages might be named, such as better light, and more room 
 for the shipwright, and greater conveniences in shoring than on any o'her 
 Dock ; and also ability of being removed from one location to another, 
 and independence of the titles, unknown to oilier Docks. I would not 
 be understood as attempting to specify in detail, the advantages of your 
 plan of Dry Dock, but merely to allude to a few of the most prominent 
 ones. 
 
 " I would also remark, that your plan is the cheapest method, at least 
 hitherto devised, of bringing the requisite power to bear in the right way 
 for raising vessels, for repairing and coppering : and I can hardly con- 
 ceive how any thing cheaper could be invented, than yours, if construct- 
 ed with economy and mechanical skill. 
 
 " I assure you I shall have no hesitation, if called upon for an opinion, 
 to recommend to the United States Government, to construct a Floating 
 Dry Dock upon your plan, forthwith, for the use of the Navy. The rea- 
 sons which I should give are, that great breadth, so much required for 
 steamers, is an advantage to the stability of this Dock, and the facility of 
 extending its length to the extreme of steamships : second, its cheapness; 
 and third, the short time it would require to erect and put one in effi- 
 cient operation. A Dry Dock on your plan can be built in a few months, 
 whereas it will take some years to complete the Excavated Dry Dock, 
 now begun at this yard. 
 
 u The premises of the United States, at this place, are well adapted to 
 receiving a Dock on your plan as any requisite depth of water can be ea- 
 sily procured at a trifling expense with a dredging machine. " 
 
 " The Naval service demands a Dry Dock at New-York, without de- 
 lay. The efficiency and advantages of yours, ^induce me to say, unhesi- 
 tatingly, that the subject of building one for the use of the Navy, is enti- 
 tled, in my opinion, to the immediate attention of the Government. " 
 
 (K.) 
 
 Extract from the Report of a Select Committee of the Common Council 
 of the City of New-York, on the subject of a Dry Dock, to raise the 
 U. S. Ship of the Line Franklin, adopted unanimously on the 
 12th day of June, 1843. 
 "In case this plan should fail, (which is not at all probable, in the opin- 
 ion of your Committee,) there is a Sectional Floating Dry Dock in this 
 port, at the foot of Rutgers-street, East River, capable of raising so large 
 and heavy a mass. This is the same Dock which took up the U. S. 
 Ship Vi nee ones, last summer to the great satisfaction of the Government 
 which has raised repeatedly the largest class of merchant ships, on five 
 only of the seven sections composing the Dock, and is certified by a 
 large number of shipping merchants and shipwrights, to be decidedly the 
 best plan of any Dry Dock hitherto devised. 
 
 This Dock is of the elevating kind— raises the vessel entirely above 
 the surface of the water, exposes her bottom fully to the light and air, af- 
 fords ample room around her hull for the workmen, and holds her in a 
 gentle and easy manner, secure against any strain or danger of any 
 kind. Its clear lifting capacity is stated to be about 2,000 tons, and its 
 power available for raising the Franklin, would be about 1,700 tons. 
 
24 
 
 It is evident, therefore that when the sh'p is cut down to a razee, and her 
 weight reduced to 1.20 l tons or there-a bouts, this Dock can easily raise 
 her high and dry above the water; but as she would have to be out of the 
 water many months, and this Dock could not properly be withdrawn 
 from the commercial marine tor so long a time, your Committee pro- 
 posed to inquire what arrangements could be adopted to secure this es- 
 sential ptnect. A plan has been submitted to your Committee, which 
 strikes them not only as feasible, but as presenting a far better method 
 of accomplishing this purpose than an Excavated Stone Dock, or any 
 other known process can afford. The plan is as follows : a strong cra- 
 dle could be constructed under her bottom, and securely bolted to the 
 ship. To the bottom of this cradle, two sliding ways, (exactly to con- 
 form to the permanent launching ways from the ship-house,) could be 
 attached. After this was completed, the ship could then be let down, and 
 by means of powerlul crabs and windlasses, aided by blocks and pulls, 
 could, without any oifiiculity, be hauled upon the permanent launching 
 ways running out from the ship-house, the ends of which are about twelve 
 feet under water, at high water mark. It may be proper to add, that this 
 plan of taking out the ship, emanated from one of the most distinguished 
 Naval architects in the country ; and there can be no doubt of its complete 
 success. Should the Navy Department have any doubts of the practica- 
 bility of this plan, there would be no difficulty in obtaining responsible 
 contractors to undertake to do the work. 
 
 After having hauled the ship into the ship-house, the advantage of repair- 
 ing her under cover in a dry. light, airy ship-house, where the work could 
 be done at leisure, would be obvious, while in a Dry Dock, the work 
 would have to be performed at perhaps a disadvantage, and the ship would 
 not be in as favorable a position for re-building, as the labor would have 
 to be done in a cramped space, without light and air to dry the ship; and 
 it has been estimated that the ship can be repaired at a cost of $20,000 
 less in a ship-house, than in a Stone Dock or any other Dry Dock, and 
 would be worth from $20,000 to $30,000 more when completed. " 
 
 (L.) 
 
 The undersigned, Port "Wardens of the City of New- York, being by 
 their occupation brought in contact with shipwrights, ship owners, and 
 Dry Docks, and being well acquainted with the various plans of Dry 
 Docks in use in this City, and with public opinion in relation thereto, 
 do hereby certify, that we unhesitatingly declare, the Sectional Floating 
 Dry Dock, in our opinion, to be far the best plan that has come to our 
 knowledge, and that such is the opinion of all disinterested persons com- 
 petent to jud^ie throughout the community. It raises the vessel in the 
 most easy, safe, cheap, and expeditious manner, affording better facili- 
 ties for shoring and seaming the vessel than any other plan of Dock 
 known to us, holding the vessel in the most convenient position possi- 
 ble for making repairs, and, in our opinion, admirably adapted to the use 
 of the Navy, affording the most convenient and effective Dock, for com- 
 paratively small cost. 
 
 We are well acquainted with the Balance Floating Dock, which is in 
 use here on a small scale. Plans, nearly the same, have been in use for 
 
25 
 
 many years, and we consider it, in every way, inferior to the Sectional 
 Floating Dock, in plan, and every other important respect, possessing 
 less conveniences, light, air, and room for the workmen, being less safe 
 for the vessel, and less secure against injury to its own structure, and 
 having much less efficiency for practical purposes. 
 
 With the facilities which we have to enable us to form a correct judge- 
 ment on the subject, we have no hesitation in recommending the Sec- 
 tional Floating Dock to the Government, for the use of their Navy. 
 (Signed.) 
 
 WILLIAM TYACHE, 
 HARRY PARSENS, 
 ANTHONY MOFFAT, 
 WILLIAM NEWCOMB, 
 R. H. TITTLE. 
 
 New-York, 30th June, 1S43. 
 
 (M.) 
 
 We, the undersigned, Civil Engineers, Shipbuilders, Shipwrights, 
 and Ship owners, being familiar with the construction and operation of 
 the Sectional Floating Dry Dock now in use at the foot of Pike street, 
 E. R., in this city, on a large scale, and having carefully examined a 
 small dock on the same plan, worked in a permanent basin, constructed 
 for its reception, connected with level bed and sliding ways for hauling 
 ships into the yard, state, as the result of our examination, that by this 
 combined arrangement, the dock raises the ship out of the water, and is 
 floated with the ship upon it, into the shallow basin, and settles upon the 
 platform, by admitting water into the tanks, when the ship may be re- 
 paired on the dock, or by means of a hydraulic cylinder, or other power 
 hauled o^T on the permanent ways into a ship house ; and when repaired 
 and required for service, may, by the same power, be placed again on the 
 Dock, floated out of the basin, and lowered into the water. By con- 
 structing the basin as designed, of sufficient size to admit of the dock 
 being turned around therein, room is afforded to lay three sets of ways 
 on each of the three sides, extending into the yard, on which nine ships 
 may be placed at the same time, for repairs, re-building, or laying up in 
 ordinary; furnishing facilities equal to nine separate stone or excavated 
 docks, at the same time leaving the dock at liberty for temporary repairs. 
 This plan furnishes also building slips for new ships and steamers with 
 facilities for placing them in the water without incurring the risk of 
 straining or hogging them in launching by the usual way. Ships are 
 also placed by this method in a much more convenient position for be- 
 ing repaired or re-built, than in an excavated wall dock; the workman 
 having the advantage of abundant air, light, and room. 
 
 We cheerfully express our entire confidence in the utility, conven- 
 ience, simplicity, and perfect safety of this plan, and do not hesitate to 
 recommend it to the Government for the use of the Navy, as in our 
 judgment superior to an excavated stone, or any other plan of Dock 
 known to us. 
 
 WESTERVELT & MACKEY, Shipbuilders. 
 
 JAZEB WILLIAMS. do. 
 
 4 
 
26 
 
 BROWN & BELL, do. 
 
 WM. WEBB, Shipbuilder, late firm of Webb & Allen. 
 
 DIVINE BURTIS & CO., Shipbuilders. 
 
 HAYTHORN & SEERS, do. 
 
 BISHOP & SIMONSON, do. 
 
 WEBB, ROBERTSON, & CO., Shipwrights. 
 
 BUCK MAN & CASILEAR, do. 
 
 WHITLOCK & BERRIAN, do. 
 
 BAYLES & BROWN, do. 
 
 WILLIAM BENNET, do. 
 
 CORNELIUS VANDERBILT, Steamboat Proprietor. 
 
 HORATIO ALLEN, late Chief Engineer of the New York 
 
 Croton Aqueduct Department. 
 T. S. BROWN, Chief Engineer, N. Y. & E. R. R. 
 T. B. STILLMAN, Civil Engineer. 
 PAUL R. HODGE, do. 
 GEO. S. SCUYLER, do. 
 EDWARD MARTIN, do. 
 CALVIN POLLARD, do. 
 G AMI EL KING, do. 
 ASA STEBBINS, do. 
 THOS. HASSARD, do. 
 
 ARNOLD MASON, ) Contractors High Bridge for 
 SAMUEL ROBBERTS, f Croton Aqueduct. 
 
 And many others not procured in time to be put in print. 
 New- York, Dec. 23, 1843. 
 
 (N.) 
 
 We hereby certify, that we have had large Steam Boats raised upon the 
 Sectional Floating Dry Dock at the foot of Pike street, and understand 
 the manner of the construction and operation, and also examined a Dock 
 upon a small scale upon this plan, constructed with a permanent Basin, 
 and Bed, and Sliding Ways for the purpose of hauling ships off the Dock 
 and have no hesitation in stating, that in our opinion, this Dock connec- 
 ted with the Stone Basin and Bed Ways, is superior to the excavated 
 Stone Dock or any other plan of Floating Dock known to us for Naval 
 purposes. 
 
 SMITH & DIMON, 
 
 Shipbuilders. 
 
 New- York, Jan. 1st, 1844. 
 
 £3=-The original documents of which the foregoing are copies, are all 
 in possession of the Secretary of the Navy. 
 
 (O.) 
 
 The expense of a Dock of six Sections, of a combined power suffi- 
 cient to raise the largest ship-of-the-line, and of a permanent Stone Ba- 
 sin two hundred and fifty feet square, constructed in as durable manner 
 
27 
 
 as an Excavated Stone Dry Dock, together with three Bed and Sliding 
 Ways, laid upon a foundation of piles, cut off at low water, and worked 
 up therefrom with stone masonry, covered with a Ship-house two hundred 
 and fifty feet square, would not exceed one-half of the cost of an old- 
 fashioned Excavated Stone Dock, at the Brooklyn Yard. A small addi- 
 tional expense would increase the bed or railways to nine in number, 
 with ship-houses over all, connected with one basin of the above size ; 
 and by extending the basin in length, two new railways could be made 
 for every eighty feet, and so on to an unlimited extent. Each one of 
 these bedways, upon which the same Dock may deliver any number of 
 ships, is in fact far better in all respects, and holds the vessels in a far 
 more favorable position than an Excavated Granite Dock on the old plan. 
 The basin and bedways would be as permanent and durable as the Gra- 
 nite Dock, and the most expensive part of the Floating Dock being con- 
 stantly saturated with salt water, would be nearly imperishable. The 
 parts of the structure that would be perishable at all, would last for a whole 
 generation, at least, and are readily renewed, as they decay, to the perma- 
 nent parts; and the whole could be replaced, if required, for the interest 
 of the cost of one Stone Dock, every four or five years. 
 
 The cost of the single Stone Dock at Norfolk was .... $974,000 
 The interest lost for several years, while the Dock 
 was building, and before it could be used, 
 
 would bring the cost up to about $1,200,000 
 
 New-York, January 1st, 1844. 
 
 (P-) 
 
 LETTER FROM H. M. SHRIEVE, ESQ., INVENTOR OF 
 THE SNAG-BOAT, &c. 
 
 Washington, May 20, 1844. 
 
 Dear Sir — I have the honor to acknowledge the receipt of your letter 
 of the 18th inst, asking my opinion of the practicability and utility of the 
 Sectional Floating Dry Dock Basin and Railways, for the use of the 
 Navy, a model of which is now exhibiting by Messrs. Dakin & Moody, 
 at the Capitol. 
 
 In reply, I have to state, that I have examined the model at the Capi- 
 tol, in all the various operations of raising ships, and hauling them off 
 on the Railways, and have come to the following conclusion : 
 
 First, That the ship is taken up and placed upon the Railway, and 
 again removed to a floating position, almost without the possibility of 
 injury to the vessel. 
 
 Secondly, That when the ship is on the Railway she is in the open 
 air, where the bottom will dry, and be in a condition to receive the ne- 
 cessary repairs in a much shorter time than if placed in the Ordinary 
 Dry Dock. The workmen will also have the advantage of the open air, 
 instead of being confined in a damp enclosure. Again, there will be a 
 vast saving of labor in favor of a Railway in removing the timber, and 
 other materials, to and from the ship undergoing repairs ; for instance, 
 the ship is placed in a dock surrounded by a wall, or in a box of a float- 
 
28 
 
 ing Dry Dock ; it cannot then be approached without passing over the 
 inclosure ; whereas, the ship on the Railway has no obstructions to pre- 
 vent a free access from every side. From these, and other important 
 considerations, I have no hesitation in giving my opinion decidedly in 
 favor of the Sectional Floating Dry Dock Railway and Basin, over all 
 others I have examined, or had any knowledge of, as being the safest in 
 its operation, and much the most economical both for repairing and 
 building vessels of all classes. 
 
 Very respectfully, 
 
 Your ob't servant, 
 
 HENRY M. SHRIEVE. 
 
 Hon. E. J. BLACK, 
 
 House of Representatives, Washington. 
 
 (Q-) 
 
 TO THE PUBLIC. 
 
 Office of the New-York Floating Dry Dock Co., ) 
 New-York, Oct. 25th, 1S45. ] 
 
 As a number of contradictory statements have been made by indivi- 
 duals, and the public press of this city, relative to the raising of the 
 Great Britain upon the Sectional Dock, the Company deem it due to 
 themselves and the public, to give a correct account of her being dock- 
 ed, and the reasons for not elevating her entirely above the water, as 
 many may suppose that the dock was incapable of lifting her. 
 
 On the day of her arrival at this port, Captain Hosken and Mr. Irvin 
 called at the office of the Dock and contracted with the company to raise 
 the ship eight feet, for the purpose of repairing her propeller. We, how- 
 ever, supposed that we should be allowed to raise her entirely above the 
 water, if it should be found that we had the necessary power. 
 
 After her cargo had been discharged, she left the pier where she was 
 moored, about 11 o'clock, A. M., and by half past 12 was placed over 
 the dock, centered, the bilge blocks adjusted, and the pumps put into 
 motion. They were kept to work until about 2 o'clock, having then 
 raised her 7| feet, when we were informed by the commander, Captain 
 Hosken, that, as the shaft of her propeller was above the water, she was 
 raised sufficiently for his purpose ; that we had performed our part of the 
 contract, and that he did not wish, and would not allow us to raise her 
 any higher. We therefore stopped our pumps, and immediately a num- 
 ber of workmen were engaged at her propeller. Thus it took but three 
 hours from the time she left her berth to the time the mechanics com- 
 menced their repairs upon the propeller. 
 
 The register of the Great Britain in England is 3443 tons. Her dis- 
 placement of water, or weight light, is about 2300 tons gross, and in 
 raising her 7| or 8 feet, we had lifted about 1700 tons, leaving but 6 or 
 700 to be raised to elevate her entirely above the water. 
 
 We have in our dock 8 sections, 7 of which have a clear lifting capa- 
 city of 300 tons each, and one of 450 tons, making 2550 tons over and 
 above the weight of the part of the dock above water ; and to obtain this 
 
29 
 
 power it would be necessary to immerse but a small portion of the end 
 floats. This power is obtained by exhausting water from immense tanks 
 placed in strong truss frames, beneath the ship. The weight of the ship 
 is sustained bv these frames, and does not bear upon the machinery at all, 
 except in a very small degree when we immerse the end floats. 
 
 Upon sounding our tanks, alter the Great Britain was raised, we found 
 that not over two-thirds of the water was exhausted from them. This 
 demonstrates beyond the possibility of doubt that we had an abundance 
 of power to elevate the Great Britain entirely above the water, and had 
 we been allowed to drive the pumps but one hour more this would have 
 easily been accomplished. It is established that the power of the Dock 
 can be applied with safety, as it has frequently been done by exhausting 
 all the water from some one of the sections, and immersing the end floats 
 for the purpose of straightening s.:ips and steamers. 
 
 In consequence of not being allowed to raise the dock above the water 
 the pumps were entirely submerged, and, as the valves are not tight, the 
 water slowly ran into the tanks through the pumps. 
 
 This made it necessary to start the pumps for a few minutes, two or 
 three times a day during the time she was on the dock. After the pro- 
 peller was prepared, the ship was lowered and put to float in 30 minutes. 
 
 During the time the ship was on the dock we repeatedly requested per- 
 mission to raise her entirely above the water, but it was not granted. 
 
 In proof of the above statement, we annex letters received from 
 Richard Irvin, Esq., and Captain Hcsken, and leave it with an intelli- 
 gent public to judge of our ability to raise entirely this ship, or any other 
 that could be placed on the dock, of not over 25U0 tons weight. 
 
 To our friends we tender our sincere thanks for their countenance and 
 the patronage bestowed upon us, and hope to meet a continuance of their 
 favors. 
 
 In respect to those whom rival interests have made enemies, and whom 
 the triumphant success of our dock in this and many other instances has 
 embittered with envy and malice, and who are ever ready t^ slander our 
 establishment in private, and assert the grossest falsehoods about us, in 
 public advertisements and newspaper communications, we do not intend 
 to take any farther notice of any thing they may say or publish on the 
 subject, as the dock has now been in operation about 5 years, and suc- 
 cessfully raised between 1500 and 1600 vessels of almost all classes, 
 many of them the largest packet ships and steamers, and its reputation is 
 too well established to be disturbed or injured by any thing they may do 
 or say. We will venture to exoress the hope that they may hereafter, as 
 citizens of this city, be proud that New- York has a dock capable of rais- 
 ing the Great Britain. 
 
 Published by order of the 
 
 New- York Floating Dry Dock Company. 
 
 Office of the N. Y. Floating Dry Dock Co. ) 
 
 New-York, Oct. 21. 1S45. J 
 
 Gentlemen — I take the liberty of addressing you in behalf of the 
 New-York Floating Dry Dock Co., upon whose dock the steamboat 
 Great Britain is now raised sufficiently high to admit of repairing her 
 
30 
 
 propeller, to solicit you to allow us to take her entirely out of the water. 
 It is true that nearly three-fourths of her weight is now upheld by the dock, 
 but as there is ample power in the dock to sustain the remainder, and 
 elevate her wholly high and dry, our company are desirous of availing 
 themselves of this occasion to exhibit the capacity of their dock, and show 
 its ability to raise the largest class of ships. They are the more anxious 
 to make this demonstration of the power of the dock, from the fact that 
 some doubt has been expressed whether their plan of Dry Dock could be 
 safely extended so as to raise the largest class of ships of war, and as the 
 entire elevation of the Great Britain will tend to overcome, if not 
 wholly to remove such doubt, the company wish, on their own account, 
 as well as that of the public, to embrace this opportunity to demonstrate 
 the fallacy of the objection by raising her entirely out of the water. 
 
 Very respectfully, your ob't servant, 
 
 R. MOODY, Secretary. 
 
 To Capt. James Hosken, R. N., and Richard Irvin, Esq., agent of 
 steamer Great Britain. 
 
 New-York, Oct. 25, 1845. 
 
 Gents — I enclose a letter from Captain Hosken, which so fully replies 
 to yours of the 21st inst., addressed to him and myself, that I have 
 nothing to add except to express my confidence in your dock, and my 
 entire satisfaction with its performance in the case of the steamer Great 
 Britain. 
 
 Yours respectfully, 
 
 RICHARD IRVIN. 
 
 To the President and Directors of the N. Y. Foating Dry Dock 
 Company. 
 
 Great Britain Steamship. > 
 New- York, 24th Oct., 1845. / 
 
 Gentlemen — In reply to your request to raise this ship completely out 
 of water, I have to say, that as there was no necessity on our part for the 
 operation, I felt myself obliged to decline acceding to it. At the same 
 time I must express my entire conviction of the capacity of your dock, to 
 effect your proposition. I may also state to you that I entertained this 
 opinion more than a year since, and made a report to my Directors, that 
 in the event of the emergency arising, your Dock could do it. 
 
 The Great Britain displaced about 2300 tons, when placed upon your 
 dock, and was raised 1\ feet in one hour and thirty-seven minutes, with- 
 out the slightest appearance of strain in any part of her. This left about 
 700 tons water borne. You subsequently lifted her a little higher at my 
 request, leaving about 600 tons water borne ; and then, from my own ob- 
 servation, I have no doubl you had about 800 tons lifting power left. 
 
31 
 
 The power exerted having completely coincided with the calculation you 
 had previously made me acquainted with, and the result agreeing with 
 the known displacement of the ship. 
 
 I remain, gentlemen, your ob't servant, 
 
 JAMES HOSKEN. 
 
 To the President and Directors of the New-York Floating Dry Dock 
 Company. 
 
(R) 
 
 2Sth Congress, House of Reps. 
 
 1st Session. Doc. No. 146. Navy Depart. 
 
 DRY DOCK— NEW-YORK HARBOR. 
 
 REPORT 
 
 OF 
 
 THE SECRETARY OF THE NAVY, 
 
 RELATIVE TO 
 
 The construction of a Dry Dock in JVev)-Yorh harbor, upon the plan of 
 using, as an elevating power, the water of the Croton aqueduct, fyc. 
 
 February 19, 1844. 
 Read, and referred to the Committee on Naval Affairs. 
 
 Navy Department, February 12, 1844. 
 
 Sir — In obedience to the requirements of an act of the Congress of the 
 United States, passed March 3, 1843, in these words : 
 
 " And the Secretary of the Navy is hereby directed to cause an exam- 
 ination to be made of the expediency, practicability, and probable expense, 
 of constructing a dry dock in the harbor of New- York, upon the plan of 
 using, as an elevating power, the water of the Croton aqueduct, and of 
 sufficient capacity to rebuild or repair a 74-gun ship ; and to cause an 
 examination of any other plan or plans of a dry dock, or floating dock, 
 in said harbor, deemed worthy by the Secretary to be reported upon ; and 
 to report the result of such examination, with his opinion thereon, to the 
 next session of Congress — 
 
 The Secretary of the Navy has the honor to report that, in October last, 
 the engineer of the Bureau of Yards and Docks, Wm. P. S. Sanger, Esq. 
 was directed to make the necessary examinations of sites for the propo- 
 sed Croton-water dock. He was assisted in his arduous labors by Messrs. 
 George F. De la Roche and Calvin Brown, scientific engineers and 
 draughtsmen, employed in the civil department of the naval service. 
 
 Three sites were examined within the limits of the city of New-York, 
 with reference to the use of the Croton water as an elevating power. 
 
 The first was at Bellevue, on the alms-house lot. 
 
 Though this site contains room enough for a dock, it is not sufficient- 
 ly spacious for a navy-yard, and has the further objection of flats or shoals 
 in front, which would prevent the access of the largest ships of war; and 
 the bed of the river at this point being rock, covered only by a thin depo- 
 site of mud, excavation, for the purpose of deepening the channel, would 
 be impracticable ; and the site is not considered suitable. The plan of 
 this site accompanies Mr. Sanger's report, marked No. 1. 
 
33 
 
 Doc. No. 146. 
 
 The second point examined was nt Kip's Bay. Here a depth of water is 
 found sufficient to float the largest ships at all times of the tide, and the 
 site is beyond any injurious influence from the currents caused by the 
 waters flowing through Hellgate. It is also sufficiently near to the cen- 
 tral parts of the city to obtain readily workmen and materials. The 
 grounds about this site, however, are very irregular ; and the grading for 
 a navy yard, and the rock excavations for a dock, would be very expen- 
 sive. Plan No. 2, accompanying Mr. Sanger's report, exhibits the form 
 and features of this site. Plan No 3, represents the arrangement of the 
 dock. 
 
 Harlaem cove, at the mouth of the Harlaem river, and opposite to the 
 south end of Great Barn island, was next examined. This site is shown 
 on plan No. 4, of Mr. Sanger. The larger portion of the ground being 
 a low marsh covered with water at ordinary high tides, and the mud being 
 some twenty feet deep, would require great expense in filling and in piling 
 for solid foundations. 
 
 The estimated cost of a dock at this site is $1,716,996. 
 
 There would be great danger in approaching this point with ships, ow- 
 ing to the rapid currents in and about Hellgate. This site was examined 
 by a commissioner in 1836, and reported as unfavorable, which opinion 
 is confirmed by Mr. Sanger. 
 
 It will be perceived, from the report of the engineers, that it is practi- 
 cable to construct a dry dock in New-York, upon the plan of using the 
 Croton water a< an elevating power. The expenses of such a work for 
 one dock at Kip's bay (the only point examined, where it is considered 
 safe to construct the work) is estimated at $1,580,835, exclusive of the 
 cost of land, and of the water to be obtained from the Croton reservoir, 
 of the amount of which no reliable estimates could be procured. The 
 expediency of constructing such a work remains to be considered. 
 
 One of the principal advantages of a lock-dock over the excavated 
 dock, where the tides do not drain the excavated dock at their ebb, was 
 formerly considered to be their easy drainage ; but, since the introduction 
 of pumps driven by steam-power, this advantage has become of minor 
 importance, and the cost of procuring the Croton water, it is believed, 
 would exceed the expense of draining by steam. A lock-dock would, 
 undoubtedly, be dryer than an excavated dock, which must always be 
 more or less wet, from the constant oozing in of the tide. 
 
 Another advantage resulting from the elevated and dry position of 
 lock-docks, is, that houses can be erected over them, aud the ships be 
 thus kept from the action of the water and the weather at the same time. 
 But these advantages, it is believed, may be obtained in a more effective 
 aud cheaper mode, by a plan which will be spoken of in another part of 
 this report. 
 
 The expense of a lock-dock at Kip's bay, or at any other point, would 
 be very large, and, without a navy-yard connected with it, the advantages 
 would be limited. To connect with it a navy-yard, would require the 
 erection of workshops, ship-houses, storehouses, and machinery, indis- 
 pensable in such an establishment ; and it would also supercede and 
 render useless the like kind of works, which have been built at the Brook- 
 lyn yard at a cost of more than a million of dollars. 
 
 5 
 
34 
 
 Doc. No. 146. 
 
 After a careful examination of the several reports made at different 
 times by the commissioners and engineers who have had the subject of 
 a new location for a navy-yard on the waters of New-York confided to 
 them, and deliberate consideration of the different points discussed and 
 explained in those reports, the conclusion seems forced upon the mind 
 that it is inexpedient to change the location of the navy-yard at Brook- 
 lyn, and that the Croton water cannot be beneficially used as an elevat- 
 ing power for a dry dock. 
 
 The Secretary of the Navy was directed, in the said resolve, to cause 
 an examination of any other plan or plans of a dry dock, or floating dock, 
 in said harbor, deemed worthy by the Secretary to be reported upon, and 
 to report the result of such examination, with his opinion thereon, to the 
 next session of Congress. 
 
 There have been two such plans of docks examined ; first, the ordi- 
 nary excavated stone dock, similar to those of Charlestown and Norfolk ; 
 and the sectional floating dock. 
 
 In the early history of the navy, the repairs and examinations in bot- 
 toms of ships were made by heaving the ship down — a process both costly 
 and hazardous. Early efforts were made by the Government to intro- 
 duce the use of the dry dock, both for repairs and shelter. In a report of 
 the Secretary of the Navy, in December, 1798, it is said : " Docks will be 
 highly necessary in repairing our ships, to avoid the tedious, expensive, 
 and sometimes dangerous operation of heaving down. They can, un- 
 doubtedly, be made in eastern States, where the tides rise very consider- 
 ably — probably in New Hampshire, Massachusetts, and Rhode Island. 
 Whether they cau be made with equal advantage, or to answer valuable 
 purposes, to the southward of Rhode Island or New-York, I cannot form 
 an accurate judgment from any information I possess ; though it would 
 unquestionably be a great public advantage to have a dock at the entrance 
 into the Chesapeake bay, and another still further south, if circumstances 
 will permit. 
 
 In President Jefferson's message of December 15, 1802, speaking of 
 the same subject, he says : " Presuming it will be deemed expedient to 
 expend annually a convenient sum towards providing the naval force 
 which our situation may require, I cannot but recommend that the first 
 appropriations for that purpose may go to the saving what we already pos- 
 sess. No cares, no attentions can preserve vessels from rapid decay, 
 which lie in water, exposed to the sun. These decays require great and 
 constant repairs, and will consume, if continued, a great portion of the 
 moneys destined to naval purposes. To avoid this waste of our re- 
 sources, it is proposed to add to our navy-yard here a dock, within which 
 our present vessels may be laid up dry, and under cover from the sun. 
 Under these circumstances, experience proves that works of wood will 
 remain scarcely at all affected by time. The great abundance of running 
 water which this situation possesses, at heights far above the level of the 
 tide, if employed as is practised for lock navigation, furnishes the means 
 for raising and laying up our vessels on a dry and sheltered bed ; and 
 should the measure be found useful here, similar depositories for laying 
 up, as well as for building and repairing vessels, may hereafter be under- 
 taken at other yards offering the same means." 
 
35 
 
 Doc. No. 146. 
 
 Before the introduction of steam-power for the purpose of drainage, it 
 was deemed important to place a dock where the ebb and flow of the tide 
 were sufficient to float a ship into the dock, and drain it by the same natu- 
 ral power ; or to place the ship ov lockage so high, that the dock would 
 be drained by opening its sluice-ways. Since the introduction of steam- 
 power excavated docks are kept tolerably well drained at a cheap rate, even 
 where their beds are below the surface of the water, by pumping. 
 
 The general advantages of docking, over the old mode of heaving 
 down, consist in the safety to the ship, and facility to the workmen in 
 examining and repairing ships' bottoms; in economy of time and ex- 
 pense ; and in the opportunity it affords of a more thorough examination 
 of the defective parts. 
 
 The first dock in the United States was built in Charlestown, and is 
 capable of docking the largest ships. The estimated cost, as stated in the 
 report of engineer Loammi Baldwin, Esq., was $280, US9 ; the actual 
 cost was $677,089. The cost of the dock at Norfolk was $962,459. 
 Both these are stone docks. 
 
 No detailed estimate of the cost of constructing a dry dock at the 
 Broklyn yard has come under the notice of the undersigned. Mr. Bald- 
 win, in his report to the department, dated December 10, 1836, says 
 upon this subject : 
 
 "The cost of a dry dock, I have learned from experience, is wholly 
 out of your reach by the ordinary calculations of detail. 
 
 "The closest calculations can never be so safe, for your present pur- 
 poses, as that of taking the mean cost of the two docks, already built at 
 Boston and Norfolk- 
 
 The dry dock at Boston, including all expenses, cost . $677,089 78 
 The dry dock at Norfolk, including all expenses . . 962,459 19 
 
 1,639,548 97 
 
 Mean cost • 819,774 48 
 
 " Hence I cannot assume safer data, that I, or any other engineer, I 
 believe, can furnish, than $820,000, for the cost of a dry dock at either 
 site in question." 
 
 This estimate is exclusive of the excavation of the channel, and crib- 
 work, to secure a suitable depth of water at the Brooklyn yard. 
 
 Mr. Sanger estimates the cost for the like work, for the dock, $750,000, 
 and the crib- work at $100,000 ; but it does not appear, in his report, that 
 this sum is derived from any estimate of the details of cost. 
 
 Excavated stone docks, in this country, where the tides do not rise 
 many feet, have but partially met the wants of the shipbuilders. Besides, 
 they are costly, confined for room, dark, and damp. They do, indeed, 
 answer for single ships; but the ship-building interest (one of the most 
 important branches of human industry, viewed in all its bearings, upon 
 the welfare of the human family) has long needed, and labored to disco- 
 ver some plan by which vessels could be built on level ways, and thence 
 launched into their destined element, without the racking and straining 
 
36 
 
 Doc. No. 146. 
 
 always incident to the ordinary mode of building and launching from in- 
 clined planes; a plan that would likewise enable them bale ly to raise 
 vessels vertically from the water, and place them high and dry, for repairs 
 or preservation. It is true, a vessel can be thus built and launched from 
 the excavated stone dock ; but such a dock is entirely too expensive to 
 be used for such a purpose, and such a length of time as would be re- 
 quired to build a large ship. 
 
 Various inventions have been essayed for the purpose of reaching so 
 desirable a result ; and floating docks, on different models, have been 
 built, and successfully used, for a number of years, in raising, repairing, 
 and launching merchant vessels, and the smaller vessels of war. JNo at- 
 tempt has been made to build ships on the floating docks ; they have 
 been used only to raise and repair them. There was still a want unsup- 
 plied — a plan by which vessels, when thus raised, could be safely trans- 
 ferred to dry land and housed , a plan by which vessels could be built, 
 standing vertically, and thus launched — avoiding the liabilities of strain, 
 hogging, and warping, incident to the building and launching from the 
 inclined ways. This desirable and important object, long so fruitlessly 
 sought, it is believed has been attained by the invention of the sectional 
 floating dock, connected with a permanent basin and level rail track. 
 Vessels of the largest size may be raised from the water, on this dock, 
 used as the elevating power ; the dock floated into its basin, settled on its 
 permanent foundation, and the ship thence transferred to the land, and 
 again safely placed upon the dock, and lowered into the water, never los- 
 ing its upright position. 
 
 S. D. Dakin, Esq., of New- York, has presented a plan of this dock, 
 and exhibited a working model of it, to the department; which seems to 
 promise the accomplishment of the great object so long sought in the bu- 
 siness of ship building. 
 
 The dock here spoken of — not connected with the proposed improve- 
 ment of a permanent basin and railway — has been in successful opera- 
 tion for several years in New- York ; and has raised, and had repaired on 
 it, numerous vessels, some of large size and great length, without having 
 experienced any accident, either to the ships or the dock. 
 
 A personal examination of the sectional dock and its working power 
 in raising and lowering a vessel of more than 600 tons, made by the un- 
 dersigned, at New- York, during the last season, proved to him very satis- 
 factory and conclusive in favor of the utility of the invention. 
 
 The proprietors claim that this dock possesses the following advanta- 
 ges : 
 
 u 1st. A perfect adaptation of the supporting power of the dock to the 
 actual shape of the vessel's bottom." 
 
 This is a great practical advantage, understood m^re fully by ship- 
 wrights than by other persons. They all agree in saying that artificial 
 methods of adjusting keel blocks in a rigid line to the shape of the keel, 
 however plausible in theory, do not work well in practice ; and that no- 
 thing hitherto devised can compare, in this respect, with the sectional 
 buoyant platforms of this dock, which are themselves buoyed up by the 
 very pressure of the water that sustains the vessel when afloat ; and each 
 
37 
 
 Doc. No. 146. 
 
 acting independent of the rest, though all in concert, must necessarily 
 hold her in her floating shape. 
 
 " 2d. Abundance of room, light, and air, around the vessel's bot- 
 tom." 
 
 The advantage in this respect is so great, that shipwrights unite in de- 
 claring that it enables them to perform their work from 15 to 20 percent, 
 cheaper on this, than on any other dock, and to inspect the minutest 
 damages or defects of the vessel's bottom. 
 
 " 3d. Ability of being elongated or contracted, according to the length 
 of the vessel, and of being separated, by taking the sections apart, into 
 two or more docks, and thus performing a great deal more efficient ser- 
 vice than any other dock. 
 
 4th. The facility with which ii can be repaired, by raising one section 
 at a time, on two others. 
 
 "5th. The short time required for its construction — not being more 
 than 8 or ID months. 
 
 " 6th. Its entire independence of the tides — being capable of operat- 
 ing at all tides. 
 
 "7th. The small expense of working it, depending upon the size of the 
 vessels ; whereas, in a stone dock, the smaller the vessel, the more the 
 expense. 
 
 "8th. Its ability to sink without ballast ; and, in sinking or rising, to 
 maintain its equilibrium, and any required position, by means of its 
 moveable and controlling end floats. 
 
 " 9th. Its adaptation, attained by its sectional arrangements, to make 
 timber and iron exert their strength in the most effective and economical 
 manner, and secure the structure against the risk of an overwhelming 
 strain bearing upon any one point. Each section is, indeed, with a 
 limited lifting power, to which its strength is adapted, acting independ- 
 ently, and yielding in the water if any pressure beyond that amount tends 
 to come upon it. 
 
 " 10th. Ability to be easily moved from place to place — an advantage 
 at all times of much convenience, and, in case of an anticipated attack 
 on the navy-yard, of the greatest moment." 
 
 Such are the advantages claimed for this dock, independent of any con- 
 nection with a permanent platform and rail-track. 
 
 The engineer, Mr. Sanger, was directed to examine the Brooklyn yard, 
 in reference to the practicability of using this dock and rail-track at that 
 yard. 
 
 His report to the department, herewith transmitted, presents a detail of 
 facts connected with the subject. A dock capable of lifting the ship 
 Pennsylvania, of 120 guns, weighing, when ready for sea, 5,200 tons, 
 with permanent basin, bed-way, rail track, and all the necessary machin- 
 ery to work it, can be built for $497,000, and requires forty feet of water 
 to raise her. 
 
 The cost of dredging and crib- work, to accommodate this structure, at 
 the Brooklyn yard, would be about the same as would be required if a 
 stone dock were built there. The cost of a sectional dock, with all the 
 above-named appendages, sufficient to raise the Pennsylvania, relieved of 
 tbe weight of her armament and stores (weighing, in that state, 2,876 
 
38 
 
 Doc. No. 146. 
 
 tons,) would cost $485,000, and require 82 feet water to raise the ship, 
 and but 14 feet to float her in, and bed her on the permanent basin. 
 
 A dock to lift a second class frigate, with dock machinery and one 
 rail-track, complete, can be built for $180,000. 
 
 An excavated stone dock can accommodate, ordinarily, but one vessel 
 at a time, and, during war, would hardly afford the facilities that would be 
 needed. The Navy Commissioners, in a report dated February 17, 
 1836, state that it might require 12,000 days' labor to repair the bottom 
 of a 74. — working in the longest days of the summer. In such a case, 
 many weeks, if not months, must elapse before such a vessel could be 
 t iken from the dock, owing to the comparatively small number of persons 
 who could work upon her at once in so confined a place. 
 
 The sectional floating-dock, with rail-tracks, could accommodate many 
 vessels at once, where they would be placed with ample room, light, and 
 air around them, and giving every facility for working with despatch. 
 
 The object so strongly desired in Mr. Jefferson's message, before 
 quoted — that our vessels may be laid up dry, and under cover from the 
 sun, and which he hoped to obtain by means of lock-docks — it is believ- 
 ed may be much better, and much more cheaply obtained, by the sectional 
 dock and railway. 
 
 All experience verifies the remark of Mr. Jefferson, that " no cares, no 
 attentions can preserve vessels from rapid decay, which lie in water, ex- 
 posed to the sun," and that works of wood, laid up dry, will remain 
 scarcely affected by time. 
 
 Some of the most costly ships of our navy have rotted, and been bro- 
 ken up, seeing little more service than lying at the wharves ; while others, 
 built about the same periods, remain comparatively uninjured, in the 
 houses in which they were built. 
 
 It is believed that the sectional dock and railways will not only answer 
 for the repairs of ships, better than any other plan yet devised, but that 
 they will become the only building-ways ; and that, instead of letting our 
 ships, when not in use, lie and decay at the navy-yards, in ordinary, they 
 will be raised from the water, and placed under cover, protected from the 
 weather, upon the rail-tracks. 
 
 The plan of the sectional dock and railway commends itself to favor 
 by its cheapness and simplicity ; and if, on trial, it realizes what has 
 been promised from its use, it will enable the Government to construct, 
 at a moderate cost, a dock at each of the navy-yards, capable of accom 
 modating a number of ships at once. 
 
 After carefully considering the facts, statements, and opinions which 
 have been presented to the department, at different periods, by the officers 
 and others who have had the subject of a dry-dock at the Brooklyn yard 
 under investigation, the undersigned is fully persuaded that the plan of 
 dock of Mr. Dakin, here spoken of, is worthy of trial on a scale suffi- 
 ciently large for raising the largest ships. 
 
 A copy of a letter from Foster Rhodes, Esq., the naval constructor at 
 Norfolk, is appended, as likewise the report of Mr. Sanger. 
 
 All of which is respectfully submitted: 
 
 DAVID HENSHAW, 
 
 Hon. John W. Jones, 
 
 Speaker of the House of Represen tatives, 
 
39 
 
 Doc. No. 146. 
 
 Gosport, Va., January 22, 1S44. 
 
 Dear Sir : I received on Saturday your letter and pamphlet — u Plan 
 and Advantages of a Sectional Dry Dock," &x. , for which please accept 
 my thanks. 
 
 The lithograph enables me fully to comprehend the important improve- 
 ments you have therein delineated. The mode by which you propose to 
 take the vessel from the dock to the land, for the purpose of repair or safe 
 keeping:, and again to put her in the water, is much more simple and ef- 
 fective than anything that I suggested last winter to Mr. Bayard, the in- 
 telligent chairman of the Committee on Naval Affairs in the Senate. 
 
 In examining the plan, and reading your letter, I cannot but feel flat- 
 tered in seeing my recommendation to Messrs. Dakin and Burgess, of 
 having the centre tank in one, and the truss or frame enclosed within it, 
 for additional strength, so fully carried out. With regard to a location, 
 I do not think any place equal to the Brooklyn yard for naval purposes, 
 (if a floating dock is to be adopted,) where a basin may be dug with the 
 greatest ease, either in the meadows, or in the flat in front of the yard, 
 where the-e is abundant room for piers, slips, &c. 
 
 In looking over your whole plan, it may be termed a magnificent one, 
 truly; and although it may be drawn out too far for the navy of the pres- 
 ent day, it is on a principle that can be extended as the wants of the ser- 
 vice may require it. 
 
 The principles, details, and practicability of the plan of the dock, ba- 
 sin, platforms, &c, are highly creditable to the intelligence, industry, and 
 practical knowledge of yourself and your associates. 
 
 Very respectfully, your obedient servant, 
 
 FOSTER RHODES. 
 
 R. Moody, Esq., Washington, D. C. 
 
 REPORT OF THE CHIEF ENGINEER OF THE 
 BUREAU OF YARDS AND DOCKS. 
 
 Washington, January 23, 1844. 
 Sir: In compliance with your order of the 30th October last, directing 
 an examination of several points on the East river, in the harbor of New 
 York, in referenc ! to the construction of a dry dock, using the water of 
 the Croton aqueduct as an elevating power, &.c, I have performed the 
 duty assigned, and respectfully report : 
 
 Here follow the views of Mr. Sanger, which are omitted, in regard to the 
 proposed Croton water Dock, the construction of which he declares to be " inex- 
 epedient. " 
 
 My letter of instructions also directs me <c to examine the Brooklyn 
 Navy- Yard, and ascertain the practicability and cost of constructing a 
 floating sectional dock upon Dakin's plan, connected with a railway to 
 take the ships from the dock to the land — the dock and railway to be ca- 
 pable of taking up the largest ships-of-the-line. n 
 
40 
 
 Doc. No. 146. 
 
 This subject has engaged my particular attention, and I had several 
 opportunities of witnessing the performance of a dock on this plan, which 
 is in daily operation. This dock consists of seven sections, two of which 
 were completed and first used in December 1S40 in January, 1841, the 
 third section was added; in July and August, 1841, the fourth and fifth 
 were added; in March, 1842, the sixth was constructed ; and in August, 
 1842, the dock was extended to its present capacity. No accident has yet 
 occurred to this dock, and a statement of the number and description of 
 vessels which have been raised and repaired will afford the best evidence 
 of its safety and utility. The proprietors exhibited their register, by which 
 it appears that the following vessels have been taken out and repaired: 1 
 sloop of war, 87 ships, 53 barques, 139 brigs, 132 schooners, 17 sloops, 
 27 pilot boats, and 59 steamboats. Among the steamboats were several 
 of great length and weight. I was present when the Troy, 295 feet 
 length, was taken out, and made particular observations to ascertain if 
 the boat was strained by the operation. A line of horizontal brackets was 
 placed at intervals of about 12 feet along the centre of the deck; and af- 
 ter the boat was entirely out of the water, no change whatever could be 
 discovered in the line. This afforded satisfactory evidence that the from 
 of the boat was preserved. This dock is a very simple and ingenious 
 contrivance, and its construction and arrangements reflect much credit 
 on the projectors. The lifting power of the dock now in use is 2,140 
 tons. 
 
 The proprietors propose to construct a dock, basin, and three railways, 
 of the following dimensions and powers, for the sum annexed : The ex- 
 treme breadth of dock 120 feet, and length sufficient to accommodate the 
 Pennsylvania ; to be divided into 6 sections, each to consist of 1 sub- 
 merged tank, divided in the centre by a strong partition, and 2 end floats ; 
 the external dimensions of the tanks to be 86 feet long, 30 feet wide, and 
 9 feet 6 inches deep ; the external capacity equal to 80 feet length, 26 feet 
 width, and 8 feet depth ; the external dimensions of the end floats to be 
 each 25 feet 6 inches long, 16 feet wide, and 9 feet deep ; the depth to be 
 immersed by the power of machinery 6 feet. These dimensions will 
 furnish a lifting power in each tank equal to 532.45 tons, and in each 
 float a power equal to 78.33 tons. There being two floats in each tank, 
 the lifting power to each section will be equal to 6S9.11 tons, and the 6 
 sections will be 4,134.66 tons. The depth of tanks, 9 feet 6 inches, add- 
 ed to the height of keel-blocks, 2 feet 6 inches, will give for the requisite 
 depth of water, over and above the draught of the ship, 12 feet : thus, to 
 dock a ship of 25 fret draught will require 3S feetdepth of water. The weight 
 of the ship Pennsylvania, with her armament, stores, and crew, is stated 
 at 5,200 tons, and a dock of lifting power sufficient to raise this weight, 
 would require an additional depth of 2 feet in the tanks, and 40 feet 
 water for use. The several sections of this dock are to be connected by 
 strong beams of oak timber, and they may be arranged to accommodate 
 a vessel of any length from thirty feet to three hundred. On each side of 
 the dock is a strong framing, upon which are placed the steam-engines 
 and machinery for pumping the water from the tanks, and for forcing the 
 floats beneath the water. The proposed basin is to be 250 feet square, 
 and the side walls 1 1 feet high : the whole area of the basin to be strongly 
 
41 
 
 Doc. No. 146. 
 
 piled, and covered with a stone floor 1 foot thick : the piles to be 12 inches 
 diameter, and 4 feet from centre to centre ; and all the masonry of the 
 floor and side-walls to be laid in hydraulic cement. The estimate is for 
 three railways, each provided with an hydraulic cylinder of sufficient 
 power to draw on shore the largest ships-of-the-line ; also, two steam-en- 
 gines, each of the power of twenty horses, and provided with all the ne- 
 cessary pumps and fixtures for working the engines and cylinders, one 
 set of bed and sliding-ways, and three sets of hauling beams ; the foun- 
 dations of the railways to be piled ; the piles cut oft' two feet below ordi- 
 nary high water, and capped with timbers 12 inches thick ; the walls to be 
 2 feet 6 inches wide at the base, and 2 feet at the top for the side-walls ; 
 the centre-walls to be 3 feet at the base, and 2 feet 6 inches at the top ; 
 and all the walls to be connected by strong cross-walls. 
 
 The process of docking a ship is first to sink the dock to the required 
 depth, by admitting water into the tanks, and elevating the floats by the 
 small engines and machinery ; the ship is then placed directly over the 
 centre of the dock, the side-shores arranged, and the pumps are then set 
 in motion. As the water is withdrawn from the tanks, they gradually rise 
 to the surface, and, with them, the ship. As the ship rises from the wa- 
 ter, the end floats are forced down, and secure the stability of the whole 
 structure, while they aid in elevating the ship. After the ship is raised 
 upon the dock, the whole structure is to be floated into the basin, the water 
 again admitted into the tanks, and the dock sunk until it securely rests 
 upon the floor of the basin, a cradle is then to be placed beneath the 
 ship, the hauling beams attached, the engines and cylinders put in ope- 
 ration, and the ship drawn on shore upon the railways. 
 
 The connecting beams are so constructed, that, by keying them firmly 
 after the ship is raised, the several sections become as one structure ; and 
 should one end of a tank be filled with water by accident or design, that 
 tank could not sink below the others, it being supported by the connect- 
 ing beams ; the effect of such accident would be, the depression of the 
 side of the dock upon which the tank filled, until the additional displace- 
 ment became equal to the amount of water admitted into the tank ; this 
 effect would be immediately counteracted by driving the end floats into 
 the water or by exhausting more water from the remaining tanks. The 
 machinery for working the pumps and end-floats is perfectly simple, and 
 the connection of one section with another is accomplished by means of 
 a hollow sliding shaft, with ball and socket joiuts ; the introduction of the 
 ball and socket joints, and moveable shafts, renders it unnecessary to pre- 
 serve a straight line of shafting, and affords a great facility for extending 
 the sections to any desired length. The power necessary to force an 
 end-float beneath the wate,r is 78.33 tons, and no additional resistance 
 would ever be applied to the machinery used in forcing these floats down. 
 The common lifting pump, with butterfly valves, is used for exhau&ting 
 the tanks ; and I apprehend no difficulty in constructing all the machin- 
 ery with sufficient strength to guard against accidents. The pump-work 
 is a small item of expense, and the cost of a duplicate set would be a very 
 inconsiderable amount. 
 
 By introducing gauge-rods, properly graduated, the lifting power exert- 
 ed by each section may be ascertained with mathematical precision ; the 
 6 
 
42 
 
 Doc. No. 146. 
 
 weight of ships placed upon the docks may thus be readily and accurately 
 obtained. The sections of this dock may be disconnected at pleasure, 
 and formed into two docks of three sections each, or one of four, and the 
 other of two sections, and, if required, maybe merged into three docks 
 of two sections each. Such small docks would be capable of taking out 
 brigs or schooners, and could be used independently of each other. The 
 practicability of constructing an hydraulic cylinder of power sufficient to 
 draw the ship from the dock upon a level railway, does not admit of a 
 reasonable doubt, when it is well known that large ships are not only 
 drawn up on an inclined plane, by the methods usually adopted upon the 
 common marine railway, but are also raised vertically from the water, 
 by means of hydraulic cylinders, as applied at the screw-docks. A serious 
 objection, alike common to all plans of floating docks when extended to 
 a capacity sufficient to raise the largest ships-of-the-line under all circum- 
 stances, is the great depth of water necessary for their operations. The 
 weight of the Pennsylvania, when ready for sea, is stated to be 5,200 tons, 
 and her draught of water 25 feet. Should it be necessary to dock this 
 ship in such condition, a depth of at least 40 feet would be required. To 
 obtain this great depth at the Brooklyn yard, it will be necessary to per- 
 form a large amount of dredging ; and to preserve it, there should be a 
 line of crib-work constructed around the wall, about the flats. A line of 
 crib- work 800 feet long, and of proper dimensions and construction, will 
 cost $39,200, and the excavations around the yard will cost the additional 
 sum of $111,158. The proprietors propose to construct a dock, basin, 
 and all the necessary machinery as already described, the dock being ca- 
 pable of raising 5,200 tons, for the following sums : 
 For the dock, basin, railways, and all machinery . . $497,000 00 
 For 800 running feet of crib-work .... 39,200 00 
 For excavating the channel 111,158 00 
 
 $647,358 00 
 
 The following statement will show the weight and draught of a vessel 
 of each class when in ballast trim. 
 
 JNames of Vessels. 
 
 Weight of hull 
 and ballast. 
 
 Mean draught. 
 
 
 Tons. 
 
 Feet. 
 
 Pennsylvania ..... 
 
 2,S76 
 
 17.5 
 
 North Carolina 
 
 2,268 
 
 17 
 
 Franklin ...... 
 
 1,836 
 
 16 
 
 Congress 
 
 1,455 
 
 15.33 
 
 Macedonian ..... 
 
 1,033 
 
 14.83 
 
 Saratoga ...... 
 
 536 
 
 11.83 
 
 Vandalia ...... 
 
 491 
 
 11.53 
 
 Yorktown ...... 
 
 412 
 
 11.41 
 
 Dolphin 
 
 140 
 
 8.95 
 
43 
 
 Doc. No. 146. 
 
 A dock of lifting power sufficient to raise the largest ship when reliev- 
 ed from the weight of her armament, stores, &c, would require for its 
 operation a deptli of water equal to 14 feet in addition to the draught of 
 the ship. Thus, to dock the Pennsylvania, the requisite depth would be 
 32 feet; and the cost of a dock, basin, three railways, and all the neces- 
 sary machinery, would be $485,000 00 
 
 For 800 running feet of crib-work .... 39,200 00 
 For excavating the channel ...... 43,153 60 
 
 $567,35S 60 
 
 I am of the opinion that the construction of a dock upon this plan, 
 capable of raising the largest ships-of-the-line, would be practicable. 
 
 In the performance of the duty assigned me, I have availed myself of 
 all the information to be obtained from the reports of former examina- 
 tions in relation to the location of dry docks and navy-yards. These 
 surveys and examinations have been attended with much labor and ex- 
 posure ; and I cannot forbear an expression of the great satisfaction I 
 experienced from the prompt and efficient manner in which the several 
 duties were performed by Messrs. George F. De la Roche and Calvin 
 Brown, the gentlemen associated with me. 
 
 Very respectfully, your obedient servant, 
 
 WM. P. S. SANGER, Engineer. 
 
 Hon. David Henshaw, 
 
 Secretary of the Navy. 
 
 28th Congress, (SENATE.) (134) 
 
 1st Session. 
 
 REPORT 
 
 OF 
 
 THE SECRETARY OF THE NAVY, 
 
 COMMUNICATING 
 (In compliance with a resolution of the Senate) 
 Plans and estimates for the construction of a dry dock at Pensacola. 
 
 Navy Depart3ient, February 16, 1844. 
 Sir : In Compliance with the direction of the Senate to lay before that 
 body " the plan and estimate for a permanent wharf at Pensacola navy 
 yard, as designed by James Herron, civil engineer, and approved by the 
 naval commandant of the station," &c, the Secretary of the Navy has the 
 honor to submit copies of Mr. Herron's plans and estimates. 
 
44 
 
 In obedience to the second part of said resolution, the Secretary has 
 the honor to transmit the report of W. P. S. Sanger, Esq., engineer of the 
 bureau of Yards and Docks, in favor of the plan of Dakin's sectional 
 dock, connected with a basin and railway, as affording more extensive 
 facilities than any other plan with which he is acquainted. 
 
 The estimate of the probable cost is embraced in the ofTers^of S. D. 
 Dakin and associates to construct it, hereto appended. 
 
 They offer, first, to construct a dock 115 by 165 feet, piled in the best 
 manner, with timber bottom, covered with concrete, and timber walls, 
 covered with galvanized iron, and one rail track, machinery for dock 
 complete, for $179,100. 
 
 A dock and basin of the same size, built of hewn stone, in the most 
 permanent manner, with one rail track, for $255,600. 
 
 Or, third, to construct the same dock, with a basin to admit six rail 
 tracks, or 175 feet square, of hewn stone, for $315,600. 
 
 The department has recently, in another report submitted to Congress, 
 expressed an opinion in favor of Dakin's plan of dock, connected with 
 rail tracks. This plan is believed to be eminently well adapted to the lo- 
 cality of Pensacola, and will undoubtedly afford facilities greatly superior 
 to any excavated stone dock that can be constructed. The department de- 
 cided some time since to adopt the plan of Mr. Dakin for the dock at 
 Pensacola, directed to be built under an appropriation of Congress of 
 $100,000, for building a floating dock at that place, and partly contract- 
 ed for the same, but deferred completing the contract, that the improve- 
 ment of the rail track might be added, and because the appropriation was 
 not sufficient to meet the expense of the dock on the improved plan. 
 
 I have the honor to be, very respectfully, your obedient servant, 
 
 DAVID HENSHAW. 
 
 Hon. W. P. Mangum, 
 
 President of the Senate. 
 
 Bureau of Yards and Docks, February 15, 1844. 
 
 Sir : In answer to your communication of this date, calling- for a « re- 
 port of my opinion of the plan of a dock, marine railway, or other suita- 
 ble work, (without specifications,) that will afford the greatest facilities for 
 the construction and thorough repair of vessels of war of the size of 
 second-class frigates, at the Pensacola navy -yard," I respectfully report 
 that, in my opinion, the plan of Dakin's sectional dock, connected with a 
 basin and railways for taking ships on shore, affords more extensive fa- 
 cilities than any other plan with which I am acquainted. 
 
 Very respectfully, your obedient servant, 
 
 WILLIAM P. S. SANGER, Engineer. 
 
 Hon. David Henshaw, 
 
 Secretary of the Navy.