A3 FROM THE UNITED STATES GOVERNMENT THROUGH THE SUPERINTENDENT OF DOCUMENTS I 506 Rev. Stat, prohibits the withdrawal of this book for hotne use. 4005 UF453 .A3""1917"'™"""' "*'""' ^»«l!mSii}(i™Vi!l.,fffl"'3''°"s, Unite olin 3 1924 030 759 561 Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924030759561 WAR DEPARTMENT : OFFICE OF THE ADJUTANT GENERAL COAST ARTILLERY DRILL REGULATIONS UNITED STATES ARMY 1914 CORRECTED TO JUNE 15, 1917 (Changes Nos. 1 to 6) WASHINGTON GOVEPy^MENT PRINTING OFnCE I9I7 ^■3p3^3 War Department Document No. 474 Office of The Adjutant General Wab Department, Office of the Chief of Staff, Washington, June 17, 1914- These Drill Regulations have been approved by the Secretary of War and are published for the information and guidance of all concerned and for observance by the Coast Artillery Corps, United States Army, and by the coast artillery troops of the Organized Militia of the United States. By order of the Secretary of War: W. W. WOTHEKSPOON, Major General, Chief of Staff. TABLE OF CONTENTS. Subject. Paragraphs. Chapter I. General principles 1-18 II. Assignment of personnel 19-36 III. Company formations and marching maneu- vers 37-42 IV. The battery command 43-73 V. Fire direction for batteries of the major and the intermediate armament 74^-92 VI. Kre direction for batteries of the minor arma- ment 93-109 VII. 12-inch mortar drill 110-127 VIII. 12 or 14 inch gun drill (disappearing car- riage) 128-147 IX. 8 or 10 inch gun drill (disappearing car- riage) 148-157 X. 6-inch gun drill (disappearing carriage) 158-167 XI. 12-inch gun drill (barbette carriage) 168-179 XII. 8 or 10 inch gun drill (barbette carriage) 180 XIII. 5 or 6 inch gun drill (barbette carriage) 181-189 XIV. 3, 4, or 4.7 inch gun drill 190-202 XV. General instructions for service at the em- placements 203-227 XVI. Target practice— Salutes 228-248 XVII. File and mine commands 249-275 XVIII. The fort command 276-297 XIX. The coast defense command 298-334 XX. Coast artillery inspection , 335-341 XXI. SearchUghts— Night drill 342-364 XXII. Means of communication 365-379 XXIII. Apparatus used in Are control and fire direc- tion 380-402 XXIV. Care of materiel 403-477 XXV. Storage and care of explosives 478-576 XXVI. Definitions 577-805 Appendix A. Examinations for gunners and for special rat- ings 806-820 s COAST ARTILLERY DRILL REGUUTIONS, UNITED STATES ARMY. Chapter I. GENERAL PRINCIPLES. 1. The defense of a coast line involves the use of both naval and land forces. 8. The naval forces include: (a) The active fleet, whose primary objective is the destruction of the enemy's fleet. (6) That portion of the reserve fleet assigned to the local defense of a particular part of the coast. (c) The naval coast patrol, which operates in conjunction with the shore signal stations. The land forces include: (a) The coast artillery troops, who are charged with the care and use of the fixed and movable elements of the seaward and land- ward defense of the coast fortifications, including guns, mortars, submarine mines, and torpedoes. (6) The coast artillery supports, which consists of small bodies of coast artillery or mobile troops assigned to the defense of the forti- fications against attack by raiding parties; they are under the orders of the coast defense commanders. (c) The coast guard. Which consists of a part of the mobile army concentrated at strategic points near the coast in position to oppose a landing in force by an enemy. 3. With reference to the land forces, the military preparations connected with the defense of the coast line may be divided into three groups, as follows :_ (a) Constructing, arming, and equipping permanent fortifica^ tions and making provisions for submarine defense. (6) Consti'ucting, arming, and equipping semipermanent fortifi- cations and field works for the protection of the permanent fortifi- cations against attack by small raiding parties on the landward side, or, in the case of an island, from boats from the adjacent shore. (c) The organization and mobilization of mobile troops to resist the landing of large bodies of troops near cities and fortified harbors and for the defense of strong semipermanent works on interior lines. These troops are known as coast guards. The coast guard com- mander is an officer of the mobile army, and, while entirely inde- pendent of the coast defense commander, should cooperate with him. In addition to the foregoing, divisions and field armies may be concentrated and held at strategic centers of value with reference to the whole coast line. 7 8 GENERAL PaiNCIPLES. 4. The armament employed in coast defenses consists of the fixed armament emplaced in permanent batteries and the movable armament for use in the landward defense of the permanent batteries. 5. The fixed armament is classified ae major, intermediate, and minor, depending on the caliber. 6. The major armament consists of guns of 8-iuch or greater caliber and of 12-inch mortars. The guns of the major armament employ direct fire, and are designed for attacking the sides and other vertical armor of armored vessels. Shot and shell are used with these guns. Shot are used at shorter ranges where perfora- tion of the main armor is possible, and are intended to reach the interior of a ship before explosion. Shell are used at the longer ranges to perforate or rack armor, injure unarmored parts, cause casualties among the personnel, and to destroy or impair the serv- iceability of fire control installations. The mortars use high- angle fire and are designed for attacking the decks of armored vessels. 7. The intermediate armament consists of 6-inch and 5-inch guns. These guns are designed for attacking unarmored vessels and the unarmored parts of armored ships, supplementing the fire of the major armament. 8. The minor armament consists of 3-inch, 4-inch, and 4.7-inch guns. These guns are designed for the defense of the mine fields and for supplementing the intermediate armament in the attack on unarmored vessels. 9. As applied to a coast artillery command, the movable arma- ment consists of the field and siege guns, siege howitzers and mortars, and the machine guns, assigned to the command. The movable armament is primarily intended for landward defense, but portions thereof may be assigned, wl\en desirable, to supple- ment the fire of the minor armament in seaward action. 10. The mine defense of any harbor consists of all mine materiel and mine personnel pertaining to that harbor, together with all battery commands assigned to protect the mine field. In addition to the mines proper, the mine mat&iel includes among other things mining casemates, storehouses, loading rooms, cable tanks, boats assigned to the mine defense, position-finding service for the mine fields, and the mine field searchlights. 11. As applied to a coast artillery command, the service of security is closely allied with the service of information. Both are accomplished by (a) cooperation with the Navy, (6) through the activities of small vessels employed as scouts, and (r) through observation on the part of the fort commands, the fire commands observing principally the seaward approaches, and the support commands the landward approaches. Units of the aviation corps, when available, are utilized for the service of security and infor- mation for both landward and seaward approaches. 12. The units of the tactical chain of coast artillery command are the battery command, the fire command, the mine command, the support command, the fort command, and the coast defense command, as shown in the following diagram: GENEBAI. FBINCIFIES. Baffery cotnnfam/ — BaHery command -\fr,re commanc/ Baf/ery command Baffery commaw/ Baffery Command — Battery comment/ - ^"'^ commanc/ Battery Command ~ Battery commanct Am/^s commanc/ Battery command -A ■Qupforf commanal Baffery command — Baftery commanof - ^.^^ command - Battery command — Battery command — Battery command — Battery command - f^'t-e command- Battery comma/fd — Battery command -\/t/,„e command - Batterv command -j Support command ' Battery command -\ I tt - Baffery command — Battery command - ^.^^ command Baffery command — Baffery command — Baffery command A Baffery command - f^""^ command Baffery command — Baffery command AMine command Baffery commancf -\ Support command ft . I % I 10 GENEEAL PRIKCIPIES. 13. A battery command consists of one or more guns or mortars commanded directly by a single individual, togetlier with all structures, equipment, and personnel necessary for their emplace- ment, protection, and service. The senior officer present for duty is the battery commander. 14. A fire command consists of two or more battery commands, the additional fire control stations and accessories, and the per- sonnel assigned to the fire command. The senior officer present for duty is the fire commander. If practicable, mortar battery commands will not be grouped with gun battery commands in the same fire command, nor will battery commands of the major armament be grouped with those of the intermediate or minor armament. 15. A mine command consists of such portion of the mine defense as can be controlled advantageously by a single individual. The senior officer present for duty is the mine commander. 16. A support command consists of the personnel and materiel of the coast artillery supjaorts pertaining to one fort and of their defensive works and positions. The senior line officer present for duty with the coast artillery supports is the support commander. 17. A fort command consists of all the means of seaward and landwaxd defense, including both personnel and mat&iel, located at any coast artillery fort. Unless otherwise directed by the Sec- retary of War, the senior coast artillery officer present for duty, other than the coast defense commander and his staff, is the fort commander. 18 . A coast defense command consists of a group of fort commands provided for the defense of a harbor or point of the coast. The senior coast artillery officer present for duty is the coast defense com- mander. Chapter II. ASSIGNMENT OF PERSONNEL. 19. The smallest administrative unit of the Coast Artillery Corps is the company. The law contemplates that its size shall be adjusted to the manning requirements of the particular battery or mine command to which it may be assigned. Coast artillery companies, therefore, vary in size and are to be considered as manning bodies of the gun, mortar, and mine elements of the coast defenses. 20. Coast defense commanders will assign officers and enlisted men of their commands to artillery duties. They will determine, depending upon the conditions, which elements of defense are to remain in service. All changes in the list of batteries and mine commands "in service" will be reported to the Adjutant General of the Army (through militaiy channels). {C. C. A. D. R. N0.4.) 21. As a rule, gun and mortar companies will be assigned so as to place the maxmium nmnber of fire commands in service. 22. A gun company will be divided into sections as follows: One range section, and for each emplacement, one gun section. The sections will be subdivided into detachments and details for manning the materiel to which assigned. 23. A mortar company will be divided into sections as follows: One range section, and for each pit, one pit section. The sections will be subdivided into detachments and details for manning the materiel to which assigned. 24. A mine companjr will be divided into sections as follows: One planting and loading section, one range and power section; and for each emplacement manned, one gun section. Members of the planting and loading section may also be assigned to gun sections, since in general the service of the latter will not take place simultaneously with that of the former. Sections will be subdivided into detachments and details for manning the materiel to which assigned. 25. The senior noncommissioned officer of each section, detach- ment, or detail is its chief. Each chief will command his sub- division and will be responsible for its drill, its efficiency, and the condition of the materiel to which it is assigned. 26. Manning tables for the armament and its accessories will be made out and posted in each coast defense command and will indicate accurately the precise individual assignments as follows of officers and men on duty: In each coast defense headquarters: (a) For the coast defense commander's headquarters. For the signal stations. For the boats assigned to the coast defense command. 13 ASSIGNMENT OF PERSONNEL. In each fort commander's station: (a) For the fort commander's station. (6) For each searchlight. (c) For each power plant or station. (d) For the signal stations, (c) For the fort switchboard. (/) For the boats assigned to the fort command. (.9) For the meteorological station. (A) For the tide station. In each support commander's headquarters: For each element of the landward defense. In each fire commander's station: (a) For the fire commander's stations. (6) For each power station. (c) For each searchlight assigned to the fire command. In each mine commander's station: (a) For the mine commander's stations. (6) For each searchlight assigned to the mine command. (c) For each planting and loading section. (a) For each battery section. (e) For eaci range and power section. In each gun battery commander's station: (a) For the range section. (6) For the gun sections. In each mortar battery commander's station: (a) For the range section. (b) For each pit section. 87. Details for the manning table specified in the preceding para- graph will be made as follows: For a coast defense, fort, support, fire, mine, or battery com- mand, by the coast defense, fort, support, fire, mine, or battery commander, respectively. 28. Company commanders will be required by fort commanders to keep men trained for each position of the manning bodies for fire, mine, and fort commanders' stations for which they furnish details, including an adequate reserve for the more important positions. 29. In the barracks of each company a manning table will be kept showing the assignment of each member of the company. Men excused from artillery drill will be given an assignment on this manning table. It will show also those trained and desig- nated for service in fire, nune, and fort commanders' stations. 30. Figure 2 illustrates the relations to each other of the oflicers of a fort command. 31. Coast defense commanders will be assigned by War Depart- ment orders. During the absence of regularly assigned coast defense or fort commanders, the senior coast artillery officers present for duty will perform the duties pertaining to those offices as provided in paragraphs 17 and 18. (C. C. A. J). R. No. 4.) 32. Fort commanders, fire commanders, mine commanders, and staff officers will be assigned by the coast defense cortunander. The senior fire commander will be assigned to that fire command office/-. ^/np/acefTie/jf officer. Range off/cer. Emp/acemenf officer. A^si^tanf haf/ery commander. Range officer. Emplacemenf officer. Emplacemenf' officer. Msisfanf batfery commanckr. flange officer. Emplacemenf officer. Etiiplacemenf officer. Ran^e officer: Emphcement officer. I? -If II 1 :h Y I- I Support commanc/er. H 13 14 ASSIGNMENT OF PERSONNEL. which will best permit him to succeed, in case of emergency, to the command of the fort command. {C. C. A. D. R. No. 4.) 33. Officers other than staff ofiicers will not be detailed as com- munication officers if such details will reduce the number of officers present with a battery command to less than that required by its manning table. If no officer is available, a suitable noncommis- sioned officer (preferably a sergeant major) will be designated to act as communication officer. 34. Mine commanders will assign the officers of the companies of the mine command in accordance with their special fitness. 35. Battery commanders will assign the officers of their commands in accordance with their special fitness. 36. In general, the officer next in rank to the battery_ commander will be assigned to a station or duty which will permit of his suc- ceeding to command without delay or confusion. AMien the plot- ting room is adjacent to the battery commander's station, the battery commander of a gun battery command may assign both lieutenants as emplacement officers. Chapter III. COMPANY FORMA TION S AND MAECHING MANEUVEKS. 37. To form the company. Normally a company will be formed for drill or inspection on its company parade and marched to its battery or station, but when in camp at the battery or when quartered in close proximity to the battery, may form on the battery parade. To form the company, the first sergeant takes poet 6 paces in front of where the center of the company is to rest and, facing that point, commands FALL IN. Each chief of section takes post, 3 paces in front of where the center of his section is to rest and, feeing the section, superin- tends the formation of his section. Each section assembles in two ranks with 4 inches between files and with 40 inches between ranks. Detachments and details form in order from the right according to the drill of the piece or apparatus to which assigned. Chiefs of detachments take posts in the front rank on the right of their respective detachments and are not covered by rear rank files. Chiefs oi details take post in the front rank of the right of their respective details and are cov- ered in the rear rank by the lowest odd number of the detail. Men not assigned to detachments or details assemble in the line of fUe closers. Sections are formed in order from right to left aa follows: For a gun company: Range section and gun sections (first, sec- ond, third, fourth, ete.). For a mortar company: Range section and pit sections (first, second, etc.). For a mine company: Planting and loading section, range and power section, and gun sections (one for each emplacement manned). An interval of 4 paces ia left between sections (not considering the chiefs of sections). Musicians form on line with the front rank 8 paces from the right of the first section (not considering the chief of section). Mechanics or acting mechanics take posts in the front rank on the left of their respective sections. The sections having been formed, the first se^eant commands CALL EOLLS. Each chief of section calls bis roll and faces about. The first sergeant then commands EEPOET, and each chief of section in turn from the right salutes and reports •" section present" (or names of unauthorised absentees) and takea post ia me froat rank 1 pace from the right of his section. 16 COMPANY FORMATIONS. The first sergeant having received the reports of the chiefs of sections commands CALL OFF. At this command each section calls off from right to left, the odd numbers in the rear rank, the chiefs of details and the even numbers in the front rank. The first sergeant then faces about^ salutes, and reports to the company commander, who has taken his post 12 paces in front of and facing the center of the company. The first sergeant then takes post on line with the frmt rank and 4 paces from the first section (not considering the chief of section). When the first sergeant starts toward his post, the officers other than the company conunander form in line 6 paces in front of the company, facing to the front, each ofiicer opposite the center of that half of the company wliich contains all or most of the sec- tions which he supervises at drill (thus a range officer of a gim or mortar company takes post opposite the center of the right half of the company). When there are more than three officers on duty with a com- pany, the additional officers take posts in line with the other officers in positions designated by the company co mm ander. 38. Inspection (artillery) in ranks. The company having been formed, the company commander commands OPEN RANKS, MARCH. At the command MARCH the front rank executes right dress; the rear rank and file closers march backward 4 steps, halt, and execute right dress. The company commander aligns the front rank from a position just to the right of the chief of the first sec- tion. He then moves straight to the rear andaligns the rear rank and file closers, and then takes post 6 paces in front of the chief of the first section, facing to the left, and commands FRONT. Having inspected the officers, the company commander, accom- panied by the officers, inspects each rank and line of file closers from right to left in front, and from left to right in rear. When the inspection is completed, the officers resume their posts, the company commander taking post 12 paces in front of the center of the company. From this position he commands CLOSE RANKS, MARCH. Should the inspector be other than the company commander, the latter, after commanding FRONT, adds REST, and faces to the front. When the inspector approaches, the company com- mander faces to the left, brings the company to attention, faces to the front, salutes, and accompanies the inspector. 39. Tomaich the company to its battery or station. The company is formed in column for marching by the command of the company commander, RIGHT FACE. At the second com- mand the officer on the right takes position on the left of and one pace from the chief of the first section; the officer on the left takes post on the left of and one pace from the cliief of the rear section ; all in ranks face to the right; the musician who is in rear after facing, steps up to the right of the musician in front of him ; the company commander faces to his left. The company in column is marched, halted,' and direction changed as prescribed for a column of files in Infantry Drill Regu- COMPANY FORMATIONS. 17 lalions, except that in marching, the column extends to easy marching distance without command, and in halting, all close up to facing distance without command. The company commander marches in such position as will enable him best to direct the movements of the column. 40. To post the sections. The company commander marches his company to its battery or station, and as he approaches the battery or station conunands SECTIONS POSTS. At the second command each chief of section falls out of ranks, marches his section to a point near its emplacement or station, and commands DETAILS POSTS. At the second command all details fall out, procure equipments and implements, and take their posts. Each chief of section determines whether all apparatus and material to be served by his section is in order, and reports to the officer directly over him, "Sir in order" or reports defects he is unable to remedy without delay. As soon as the chiefs of section have reported, the officers report to the battery commander, who then reports to the lire commander " in order " (insert- ing name of battery), or reports defects he is unable to remedy without delay. (The reports from mine companies are made to the mine commander.) If he so desire, a company commander may post the sections separately, at any point of the march, bj^ commanding: SECTION, POST. The section designated is posted as described above. When a range section leaves the column, the range officer falls out and proceeds direct to his station. - Details for remote stations may be marched to their stations from the company parade by their respective chiefs. 41. To dismiss the sections. Battery commanders command DISMISSED. Range officers command CLOSE STATION (or CLOSE STATIONS). Emplace- ment officers command SEPLACE EQUIPMENTS. Chiefs of sections command FOB.M SECTION. The company is formed on the battery parade and is marched by the battery commander to the company parade and dismissed. Subdivisions from remote stations are marched to the company parade and dismissed by their chiefs. 42. To form as infantry. To form for infantry drill or exercises under arms, the files fall in with the pieces at "Order." The chiefs of section salute and report with their pieces at "Order" and move to their posts with their pieces at "Trail," coming to "Order" upon halting. The first sergeant draws saber (if armed with one) before giving the command to fall in. After receiving the reports of the chiefs of section, he commands INSPECTION AKMS, OBDEB. ABMS, faces about, salutes, and reports to the company commander. The company commander returns the salute and directs the first sergeant to form as infantry, whereupon the first sergeant faces about and forms the company as prescribed in Infantry Drill Regulations, except that squad leaders do not report and that cor- 18 COMPANY FORMATIONS. porals may be placed as Nos. 1 and 4 of the front rank when the reduced strength of the company makes it advisable. As soon as the company is formed properly, the first sergeant faces about, salutes, and reports to the company commander, "Sir, the com- pany is formed." The company commander returns the salute and the first sergeant takes post. The company commander draws saber and takes his post facing to the front 3 paces in front of the center of the company. Chapter IV. THE BATTEBY COMMAND. THE BATTEEY COMUAITDEB.. 43. The battery commander will keep a record of the daily attendance at artillery drill in numbers only, showing separately those attending driU at the battery and those attencfing drill at stations not a part of the battery command. 44. The battery commander is responsible — First. That the personnel of his battery command is smart and alert at dnll and efficient in practice and action. Second. That the equipment provided for his battery com- mand is in serviceable and attractive condition and that no permanent modifications of equipment or prescribed methods are made without proper authority. Third. That the officers and men of his battery command present a tidy appearance in ranks and at then- posts and are instructed in the care, preservation, and use of artil- lery material as prescribed in these regulations and in orders. Foiu-th. That the emplacement book and other records are kept as required by these regulations and by orders. 45. The battery commander will make every effort to keep his battery command supplied with the proper equipment, imple- ments, and reserve ammunition. 46. The battery commander is not authorized to modify the drill as prescribed in these regulations, except as indicated hereinafter. If on account of local conditions it is necessary to modify the drill, it will be reported to the artillery district commander. 47. The coast defense commander, with the approval of the dis- trict commander, may authorize temporary changes in a provi- sional fire-control installation. 48. Permanent changes in fire-control installatLons (provisional or standard) or any changes in the standard installations will be made only upon authority of the Secretary of War. 49. If the battery commander improvises any device, method, or modification of the drill which in his opinion will increase the efficiency of his command, the coast defense commander may au- thorize such device, method, or modification to be used during drill or target practice for such lirnited specified time as may be neces- sary to test its merits. If , in the opinion of the coast defense com- mander, the device, method, or modification has sufficient merit to warrant its adoption for general use, a detailed report thereof will be made to The Adjutant General of the Army (through military channels), accompanied by drawings or models if necessary for the complete understanding of any devices submitted . The assistance of the proper staff officers of the coast defense command will, upon application, be given to battery commanders for the pxtrpose of con- 20 THE BATTERY COMMAND. Btructing simple devices in accordance with their ideas, provided that no unauthorized expenditure, of , funds be involved. This paragi-aph mil not be taken as authority for increasing the load upon any fortification plant without authority of the Secretary of War, nor of exemption from efHciency with the means and methods prescribed in these regulations. (C. C. A. D. R. No. 1 .) 50. Company commanders will keep range sections, telephone operators, and the details for fire, mine, and fort commanders' stations well instructed during both the indoor and outdoor periods. 61. Battery commanders will accompany the fort commander in his inspections of their respective battery commands. 52. In fort command or fire command drill or action, the battery commander's exercise of fire direction will be limited by orders which come to him from higher commanders. When BATTERY COMMANDER'S ACTION is ordered, or when communication with the fire and fort commanders is' interrupted, he will exercise independent fire control and will fight Ms battery in accordance with the general plan of action. 53. At drill or in action, the batteiy commander will go wherever Ms presence is necessary, but upon quitting Ms station he will leave information as to where he may be found. 54. In case an observing station or any element of the position finding system goes out of action the battery commander will take the necessary steps to utilize to the best possible effect such elements of the position finding system as remain serviceable. 55. Batteiy commanders will improvise some method for the direction of the fire of their batteries, relying only upon stations located at the battery. In many cases where the channel is not wide, it will be practicable to determine the approximate ranges to ships of large size by azimuths alone. 56. Battery commanders will occasionally conduct driE and subcaliber practice under emergency concfitions including the lollowiilg-: (a) Elimination of primary station only. (6^ Elimination of secondary station only. Ic) Elimination of battery commander's station only. Id) Elimination of primaiy and secondary. \e) Elimination of primary and battery commander's station. (/) Elimination of battery commander's station and secondary. (g) Elimination of sight standard and gun pointer. For mortars (d) and (/) will be omitted. An ofiicer conducting the firing of a battery under any one of the emergency conditions specified above will not communicate with any station wMch is eliminated under that condition; he will get ranges from any in- truments in any stations, except those that have been eliminated. THE RANGE OFFIOEK. 57. The range officer is in charge of the position finding equip- ment and the range section of the battery command, and Ms station is at the battery plotting room. He is responsible to the battery commander for the condition of the materiel and for the efliciency of the personnel under Ms charge. THE BATTERY COMMAND. 21 88. Before drill, pmctice, or action he will make a careful inspection of the equipment of his station, verifying the adjust- ments of the plotting board and of other apparatus. 59. Having completed the inspection, and having received the reports of the chiefs of details, he will report to the battery com- mander, "Sir, stations in order, ' ' or will report defects he is imable to remedy without delay. (See par. 40.) 60. At the conclusion of the exercises for the day he will direct that the stations be closed (par. 41), will inspect his station, and will report to the battery commander, handing him all records pertaining to the day's work at his station. OBSEHVEaS. 61. Observers will be selected on account of their special aptitude. They will understand thoroughly the use of their instruments and will have a knowledge of the general characteristic features of war- ships. Each observer is responsible for the care and adjustment of his instrument and for the police of his station at all times, and will report to the range officer deficiencies, defects, or accidental damages as soon as they are known. 62. Ranges to moving targets as determined by depression position finders and coincidence range finders will be compared frequently (if practicable) with ranges as determined by a long horizontal base. 63. Observers will be tested frequently as to their proficiency in the practical use of the instruments to which assigned. The test win be conducted so as to determine the relative ability of various observers to read quickly and accurately ranges to fixed and moviog objects. THE PLOTTER. 64. The plotter has charge of the plotting room under the range officer. He is responsible for the adjustment of the plotting board and other plotting room equipment. He will be tested frequently as to the accuracy of his prediction of set-forward points. THE EMPLACEMENT OFFICER. 65 . The emplacement officer is in charge of one or more emplace- ments. He IS responedble to the battery commander for, the condition of the emplacement mat&iel and for the efficiency of its service. 66. Before drill, practice, or action he will make a careful inspec- tion of the mat6riel under his charge, and will test the electrical firing circuit if installed. 67. Having completed the inspection and having received the reports of the chiefs of sections, he will report to the battery com- mander, "Sir, Nos. (or pit ) in order," or will report defects he is unable to remedy without delay. (See par. 40.) 68. At the conclufiion of the exercises for the day, he will com- mand EEPLACE EQUIPMENTS (pai-. 41), will inspect the emplacement, and will report to the battery conmiander. 22 THE BATTERY COMMAND. THE GTIISr AND PIT COMMANDERS. 69. Each emplacement of a gun battery is commanded by a gun commander and each pit of a mortar battery by a pit commander, who is responsible to the emplacement officer for the condition of the materiel and the efficiency of the personnel of Ms section. The gun (or pit) commander will supervise the gun cleaning and will require the mechanic to keep pieces and carriages in excellent condition. He will supervise the service of the piece. 70. The gun (or pit) commander will have charge of the entire emplacement under the emplacement officer, and during the absence of the emplacement officer, he will perform the duties prescribed for the emplacement officer. After the details have been posted as prescribed in paragraph 40, he will command EXAMINE GTTN. He will make a general inspection of the ^n carriage, paying especial attention to the recoil cylinders, the firing device, and the oiling of the various bearings. He will report to the emplacement officer, "Sir, No. (or pit )in order," or will report defects he is unable to remedy without delay. 71. At the conclusion of the exercises for the day, he will com- mand FORM SECTION after the emplacement officer has com- manded BEPLACE EQUIPMENTS (par. 41). He will supervise the replacing of equipments and implements, will see that the piece is secured, and will then form his section on the battery parade. THE GUW POINTER. 72. A gun pointer is assigned to each gun in service and is responsible for the condition and adjustment of the sight and sight standard. He will have a general knowledge of the characteristic features of warships. He will be tested frequently, as prescribed in paragraph 224. (C. C. A. D. R. No. 1.) THE MECHANIC. 73. One mechanic, or acting mechanic, is assigned, under the gun commander, to each 8-inch (or greater caUber) gun emplace- ment, to each mortar emplacement, and to each battery of the intermediate or minor armament in service. He is in immediate charge of all small stores and supplies at the emplacement or battery to which assigned. Chapter V. FIEE DIRECTION FOB BATTERIES OP THE MAJOR AND THE INTERMEDIATE ARMAMENT. (For a description of the apparatus used in battery fire direction, see Chapter XXIII.) 74. The following systems of range and position finding are in use: (a) The horizontal base system, which requires a station equipped with an azimuth reading instrument at each end of a horizontal base line. When a battery has more than one horizontal base liae, those other than the normal base line are called auxiliary base lines. Auxiliary base Unas may be obtained by using the observ- ing instrument m the battery commander's station in connection with the instrument at B' or B". (6) The vertical base system, which recjuires a single station equipped with a depression range and position finder. (c) The coincidence range finding system, which requires a single station equipped with a coincidence range finder. It the coincidence range finder is not provided with an azimuth reading device, a separate azimuth instrument is required. (d) The emergency system, which may consist of the systems specified in (6) or (c), or of some other system improvised by the battery commander. (c) Whenever, during the firing of seacoast guns and mortars, instrumental observation from shore stations or from air or water craft shows that the use of ballistic methods has failed to place the center of impact near the target, adjustment of fire based on such instrumental observation is authorized. (C. C. A. D. R. No. g.) 75. The methods described below are based on standard installa- ti ans. As far as applicable, they will be used with all installations. The fire direction for those batteries of tlie intermediate armament which are not provided with major armament eq^uipment will be as prescribed for batteries of the minor armament m Chapter VI. GTIir BATTEEY. MANNING PARTIES. 76. Battery commander's station: Battery commander. Observer. Operator for each telephone. Musicians. 24 FIRE DIRECTION — MAJOR ARMAMENT. Plotting room: Range officer. Plotter. No. 1, assistant plotter. No. 2, primary arm setter. No. 3, secondary arm setter. No. 4, range board operator. No. 5, deflection board operator. No. 0,- range' transmitter. No. 7, operator for telephone to the emergency station. Bach observing station: Observer. Reader. INDICATION AND IDENTinCATION OP A TARGET. 77. The battery commander having identified a target, indicated to him by the fire commander, as prescribed in Chapter XVII, will indicate it to his observers (at B', B'', B''' and E) and gim pointers, as follows : 1. TARGET; 2. Subarea; 3. Name (or type and class) of an isolated ship, or designation of division, formation, ship num- ber ,or any sufficient description, and at night the number of the covering searchlight. When the observers are on the target ' they report ' ' B' (B", B'^' or emergency) ON TARGET. ' ' When the gun pointers are on the target, they report "No. 3, 2, 3, or 4 on target." When the battery commander is satisfied that the target has been correctly identified by the observers, he will give the com- mand 4. TRACK. Unless otherwise specified, the system normally used at the battery will be used at the command TRACK. (C. C. A. D. R. No. 1.) 78. Some examples of commands are as follows (dashes indicate pauses to allow for transmission of the command by telephone) : 1. TARGET ; 2. OCEAN VIEW ; 3. TEXAS (ob- servers report B', B", W or emergency on target; gun pointers report No. 1, 2, 3, or 4 on target); 4. TRACK. 1. TARGET ; 2. lYNNHAVEK ; 3. OIL TANK CLASS 1-3 (observers report B', W, W" or emergency on target; gun pointers report No. 1, 2, 3, or 4 on target) ; 4. B' (or B") VERTICAL BASE, TRACK. 1. TARGET ; 2. BOCA CHICA ; 3. MONITOR DIVISION (observers report B', W, B'" or emergency on target; gun pointers report No. 1, 2, 3, or 4 on target) ; 4. B' (or B'O AUXILIARY BASE, TRACK. 1. TARGET ; 2. TOBOGA ; 3. DESTROYER DIVISION, SHIP NO. 1 (Observers report W, B", B"', or emergency on tai-get; gun pointers report No. 1, 2, 3, or 4 on target) ; 4. EMERGENCY SYSTEM, TRACK. 79. Observing and aiming points for observers and gun pointers will be as follows: 1. For all power vessels having but one funnej, that funnel will be the observing and aiming point. FIEE DIHECTIOK— MAJOB. AB.1IAMENT. 25 2. For all sailing vessels having but one mast, that mast will be used for the observing and aiming point. 3. For all power vessels having two or more funnels, the forward funnel will be the observing and aiming point. 4. For all sailing vessels having two or more masts, the forward mast will be the observing and aiming point. 5. For all vessels not included above, the aiming point will be designated. by the commander assigning the tai^et. If for any reason it is impracticable to utilize the observing and aiming points specified above, the battery commander will desig- nate other points when he indicates the target, or at any time after he indicates the target that it becomes impracticable to use the prescribed points. HORIZONTAL BASE SYSTEM. 80. The command TRACK having been given by the battery commander, each observer follows the target. At the first stroke of the time interval bell, he moves his instrument in azimuth so as to place the vertical wire accurately on the observing point, keeps it there untd the third stroke of the bell, and stops the instrument precisely on the third stroke. The reader at each station reads the azimuth and transmits it to the proper arm setter. AVhen for any reason the observing interval is not indicated by bell, the stop watch is used, and the commands READY, TAKE are given over the observer's line from the battery commander's station. (BEADY corresponds to the first stroke of the bell, and TAKE to the third stroke.) When a target is first assigned, additional observations may be taken -between bells, in order to reduce to a minimum the time necessary to furnish data to the emplacements for opening fire. The trackii^ continues until CEASE TRACKIM6 or CHANGE TARGET is ordered. No. 2 wears a telephone head set on line from B'. He sets the primary arm to the azimuth received from B' and calls "set. " No. 3 wears a telephone head set on line from B". He sets the secondary arm to the azimuth received from B" and calls "set. " The plotter places the targ accurately at the intersection of the arms and marks on the plotting board the position of the plotted point. When more than one point on a course has been plotted, he calls CLEAR, or gives a signial as soon as he has marked each new point. At this command or signal, the arm setters move their arms so as to clear the track of the target. The plotter considers the plotted track of the target and the probable course of the target, and using a prediction ruler (or other form of predictor) he marks the position of the set-forward point on the board so that it will lie on the probable track of the target. The plotter then swings the gim arm to the set-forward point and reads off the gun arm the actual range to the set-f orwardi^point (the gim arm must be set at normal) . He then moves the gun arm to the last plotted point and holds it there until No. 1 reads the angular travel and resets the tally dial and the tally subdial. (If there is considerable lost motion m the tally dial the plotter should first move the gun arm to the plotted position before the last, hold it there until No. 1 sets the tally dial 28 riEE DIRECTION— MAJOR ARMAMENT. and the tally subdial, then move the gun arm to the last plotted position and hold it there while No. 1 reads the angular travel.) Angular travel may be taken between set-forward points, but the result is not as accurate as when taken between plotted points. When travel is taken between set-forward points, No. 1 calls off the angular travel as soon as the plotter has called the range, and resets the tally dial and the tally subdial. To set the tally dial and the tally subdial, No. 1 turns the outer scale of the tally subdial until the zero is opposite the pointer, and sets the disk of the tally dial so that the 15 of the scale is opposite the pointer. No. 1 calls out the reference number corresponding to the angular travel of the target to No. 5, reading the degrees from the tally dial and the hundredths from the outer scale of the tally subdial. No. 1 operates the wind component indicator and sets the target arm to the azimuth of the gun arm, changing it when- ever the azimuth of the gun arm changes as much as 2J°. The azimuth and the velocity of the wind are received by telephone, When Case III is used. No. 1 calls off the azimuth of the set-forward point. No. 4 wears a telephone head set on the line to the emplacements. He operates the range board and the atmosphere slide rule. By means of the atmosphere slide rule, he determines (from the barometer and the thermometer readings which are telephoned to the station) the atmosphere reference niunber. He obtains the wind reference number from No. 1, who operates the wind com- ponent indicator. The height of tide is telephoned to the station. The battery commander or the range oflBcer specifies the muzzle velocity to be used on the range board. No. 4 sets the ruler to the actual range of the set-forward point as called off by the plotter, and after applying corrections for atmos- phere, wind, tide, and velocity, he telephones the corrected range of the set-forward point to the emplacements. He sends to the guns, the deflection called by No. 5 in Case II or the azimuth called by No. 1 in Case III. No. 5 operates the deflection board. He uses the angular travel called oS oy No. 1 and takes the wind reference number from the wind component indicator, which is operated by No. 1. He applies the corrections for wind, drift, and angular travel of the target in Cases I and II, and calls the sight deflection to No. 4. In Case III he determines the corrections for mnd and driit and then applies the resultant correction to the azimuth correction scale of the gun arm whenever it differs from the previous correction by 0.05 or more. No. 6 transmits to the guns by means of the mechanical or elec- trical range transmitter the corrected range announced by No. 4. (C. C. A. D. R. No. £.) 80A. When an observing instrument is located near the battery, the angular travel, during the observing interval, may be de- termined by azimuth differences as follows: (a) A paper scale is pasted on the travel scale of the deflection board (see Fig. 4, page 130), and the degree marks are numbered from 1 to 15 beginning on the right. FIBE DiaECTION— MAJOR AEMAMENT. 27 (5) The 15 on the movable scale (azimuth correction scale) is set under the 3 on the deflection scale. (c) When the first azimuth is received, a small pointer ia placed on the movable scale opposite the three last figures of the azimuth on the paper scale. (For example, for 125.35 the pointer is placed opposite 5.35 on the paper scale.) (rf) X^Tien the second azimuth is received, the movable scale (carrying the pointer with it) is moved until the pointer is opposite the second azimuth on the paper scale. (For example, for 126.23 the pointer ia placed opposite G.23 on the paper scale.) . (e) The angular travel is read from the movable scale opposite the 3 of the deflection scale. (The difference in the readings given in the examples under (c) and (d) is .88 and the movable scale will show 15.88 under the 3 of the deflection scale.) If desired, an improvised slide rule may be used instead of the deflection board. (C. C. A. D. R. No. 1.) SOB. If desired, the time range curve may be plotted on cross- section paper in the plotting room instead of on the time-range board in the emplacement, or it may be plotted in both the plotting room and the emplacement. In every case, the range drum will be set only for that elevation which corresponds to the range of the set forward point at the instant of firing; "creeping" will not be resorted to. (C. C.A.I). R. No.l.) VERTIOAL-BASE SYSTEM. 81. The range officer throws the switches so as to bring both arm setters' telephones in multiple with the reader's telephone in the station ordered. The W (or B') arm is laid aside. The observer at B' (or W) follows the target, stopping the instrument with the horizontal wire on the water line and the vertical wire on the designated part of the target, at the last stroke of the bell. The reader transmits the azimuth and the range to the arm setters. The tracking is continued in this manner until CEASE TRACKING or CHANGE TABGET is ordered. Both arm setters hear azimuth and range. If B' is sending information. No. 2, on hearing the azimuth, sets the primary arm; No. 3 notes the range and calls it to the plotter as soon as No. 2 calls "set." If W is sending informa- tion. No. 3 sets the secondary arm and No. 2 calls the range. The plotter places the targ against the arm at the range called by the arm setter, and the remaining operations are as prescribed for the horizontal base system. 82. Where instruments for both horizontal and vertical base systems are installed practice in the use of each will be held fre- quently. Special attention will be given to practice in changing from one sytem to the other. 83. The time interval bells will be cut off frequently and obser- vations taken from a watch or clock in the B. C. station, READY, TAKE, being called over the line to the observers. 28 FIRE DIRECTION— MAJOR ARMAMENT. COINCIDENCE HANOE-PINDING SYSTEM. 84. The coincidence range-finding system is similar to the vertical- base system. No. 2 sets the arm corresponding to the station, and No. 3 notes the range and calls it to the plotter, as soon as No. 2 calls "set." The telephone line from the coincidence range finding station to the plotting room should be provided with head sets for Nos. 2and3. 85. In batteries provided with a horizontal base, the coincidence range finding instrument is used as an emergency instrument. EMERGENCY SYSTEM. 86. In addition to the regular system in use at the battery, every battery should be provided with one or more additional systems for use in emergency. Batteries having the horizontal base system, should have at least one emergency station equipped with a coincidence range finder or a depression position finder. Thx)se batteries provided only with self-contained bases (either vertical or horizontal) should have additional instruments located at various points for use in emergency. MORTAR BATTERY. 87. MANNING DETAILS. B. C. station: Battery commander. Assistant battery commander. Battery commander's observer. Operator for each telephone. Azimuth keeper (who operates time azimuth board). Musician. Plotting room: Range ofiicer. Plotter. No. 1, assistant plotter. No. 2, arm setter. No. 3, arm setter. No. 4, azimuth computer. No. 5, operator of device for transmitting data to the pits. Observing stations (for each) : Observer. Reader. INDICATION AND IDENTIFICATION OF A TARGET. 88. The methods of indication and identification are the same as those prescribed for a gun battery (par. 77), except that taigets are not indicated to, or identified by, the gim pointers. JIBE DIRECTION— MAJOH, ARMAMENT. 29 HORIZONTAI. BASE SYSTEM. 89. The command TRACK having been given, the target ia plotted by means of the primary and secondary arms from azimuths taken simultaneously from B' and B" in the same manner as pre- scribed for a gun battery. (Par. 80.) PKEDICTXNG AND FIRING. 90. In the following description, shoTving the different steps in their order, both firing and predicting intervals are aasumed to be one minute. For convenience of explanation, the observations on which predictions are to be made are designated as "time 1," "time 2," etc., the intermediate (or half-minutel observations being designated "^," thus "time 1," "time IJ," "time 2," etc. After a target has been assigned, upon the command TRACK, the target ia plotted every half minute. Time 1 is the first plotted position of the target, time li is the next, and time 2 is the third plotted position, necessary to make a prediction. The prediction may then be made at time 2, and the salvo or shot fired at time 3, 1 minute after time 2. The zone should be indicated before time 2; to do this the plotter, after time IJ, the last intermediate observation before time 2, estimates the position at which the target will be plotted at time 2, and also the approximate location of the predicted and set forward points, brings up the mortar arm, calh out the zone and notes for his own use the time of flight; a well instructed plotter should be able to make this estimate without material error in the time. As soon as the position of the taiget is plotted from the observa- tions taken at time 2, the plotter calls or signals CLEAR, the pri- mary and secondary arms are moved so as to clear the course of the target, the plotter applies the predicter holding it at a,n angle of about 45° with the board, the 10-second pointers to the side toward which the target is moving, and marks the predicted and set-forward points. Then he lays the predicter to one side, brings the gradu- ated edge of the mortar arm to the set-forward point, and calls out the elevation. No. 4 immediately sets his deflection board for this elevation while No. 5 repeats the elevation over the telephone to the booth at the same time recording it on his record sheet and transmitting it by hia electrical or mechanical device. While the plotter is getting the elevation, No. 1 reads the azimuth of the set- forward point and calls it out to No. 4 after the plotter has called the elevation. No. 4 then obtains the corrected azimuth and calls it to No. 5 who records and transmits it in a similar manner as for elevation. (No. 4 instead of No. 5 may wear the telephone head set on the line to the pits.) The plotter next brings the graduated edge of the mortar arm to the predicted point and calls "set"; then No. 1 transmits the azimuth of the predicted point to the battery commander's ob- server, who sets the battery commander's instrument to this azi- muth. The pit being ready, the signal for firing is given when the 30 FIRE DIRECTION— MAJOK ARMAMENT. target crosses the vertical wire of the instrument, provided the time of crossing indicates that no considerable error has been made in prediction. This is a matter for the exercise of judgment by the battery comma,nder or his assistant, but, in general, if the time of crossing varies more than five seconds from the predicted time the command RELAY should be given to the pita. The required data having been transmitted, the jilotter notes the travel during the last minute, estimates the position of the next predicted and set-forward points, brings up the mortar arm, reads the zone number, and estimates the time of flight for the next shot or salvo. The tracking is then resumed. The predicting interval is not necessarily equal to the firing interval and is ordinarily taken as one minute. With sufficiently well-trained personnel, the firing interval may be reduced to 45 or 30 seconds and 1 minute predictions made every 45 or 30 seconds. If the battery commander's station is also the, primary station, the primary arm, instead of the mortar arm, is brought to the pre- dicted point, and No. 2 reads and transmits to the battery com- mander's observer the azimuth of the predicted point. DUTIES OF THE AZIMUTH KEEPER. 91. The azimuth keeper operates the time azimuth board. He receives his data from the plotting room and immediately calls "error" if he discovers any large error which can not be accounted for by a change of zone or other normal change. THE VERTICAL BASE SYSTEM, THE COINCIDENCE RANGE-FINDING SYSTEM, AND THE EMERGENCY SYSTEM. 92. The vertical base sytem, the coincidence range-finding system, and the emergency system are used under the same con- ditions and in the same manner as provided for a gun battery, so far as the location of the track on the plotting board is concerned. Predicting and fuing are as prescribed for the horizontal base sys- tem for mortars. Chapter VI. FIRE DIBECTION FOB BATTERIES OF THE MINOR ARMAMENT. MAMTSXffG PABTT. 93. Battery commander's station: Battery commander. Observer. Range board operator. Deflection board operator. Operator for transmiaaion device. Operator for telephone to fire (mine) commander's station. Operator for telephone to spotting station. Musicians. Spotting station: Spotter. Assistant. 94. Each member of the manning party, on reaching his station, examineG the apparatus to which assigned, makes the prescribed tests and adjustments, and reports to his chief of detail. On com- pletion of the examination, the chief of detail reports to the battery commander: "Sir, B. C. (or spotting) station in order." 95. Having identified a target indicated to him by the fire (mine) commajider, the battery commander indicates it to the observer, gun pointers, and spotters by commands similar to those prescribed in paragraph 77. 96. When satisfied that the target has been identified, the battery commander commands TRACK, whereupon the observer, the gun pointers, and the spotters follow the target. The observer an- nounces the range frequently. The operator of the range board determines and sets the corrected range on the (mechanical) transmission device. 97. The battery commander determines the travel by means of his infltrument and makes the necessary deflection corrections for wind, drift, and travel. (a) to range prom one gtjn. 98. The battery commander commands NO. — FIRE ONE SHOT ; the piece is loaded and fired, under the direction of the gun commander, at the corrected range and deflection indicated on the transmission device. With the vertical wire of his sight set at the deflection used by the ranging gun, each gun pointer follows the target by traversing the gun until the instant of splash, when he stops traversing, quickly moves the vertical wire to the splash without moving the gun, then reads and reports his deflec- tion to the battery commander. 32 FIKB DIRECTION— MINOE ARMAMENT. From the reports of the gun pointers and the spotters, and from his own observation, the battery commander causes the necessary corrections to be applied in order to place the next shot on the tar- get. Additional ranging shots are fii'ed until the battery com- mander is satisfied with his corrections, and then he commands, BATTERY COMMENCE FIRING. Range and deflection corrections are made throughout the firing as often as necesaary. During any series of firing, the battery commander is kept in- formed of the deviation of the shots by the spottera, who report at frequent intervals "Short (or over) or Hit." Filing from any gun may be stopped by ringing the gong in the emplacement therefor, or by the command NO. — CEASE FIR- ING. Firing from the battery may be stopped by setting the mechanical transmission device to read 0, by ringing all bells, or by the co mm and CEASE FIRING (given by mouth or by bugle). (b) sheaf ranging. 99. Sheaf ranging consists in firing two or more guns at the same instant with their range settings differing by equal increments and increased or decreased from the right by the specified increment in yards, observing the relative positions of target and splashes, and making corrections from these observations. 100. The battery commander designates the ranging gun and the range difference between adjacent gtrns and commands SHEAF RANGING, at which command all guns are loaded. The ranging gun is laid on the range shown on the mechanical transmission device. Other guns are laid on this range corrected for their proper range differences. All guns are fired on a signal from the battery commander. All gun pointers determine and report their deflections as prescribed for ranging from one gun. Spotters report the distance of the nearest splash from the target in terms of multiples of the sheaf, "Second (or other) splash short (or over), as third splash short ]/4. " From spotters' and gun pointers' reports and fi'om his own observation of splashes, the battery com- mander causes the necessary corrections to be applied, fires addi- tional shots from the ranging gun, or opens with the battery at once, as conditions wan-ant. 101. Ranging by sheaf is a simple method, if the spotter's station is located well off to the flank of the battery or far above the level of the gun. The distance between splashes provides a measure for estimating the distance from any splash to the target. The method is valueless when the guns are on a low site and the battery com- mander's and spotter stations are near the battery, as one splash may obscure the others. (C) EMERGENCY FIRING. 102. If the range finding system is out of action, or if there is no range finder, the battery commander ranges soleljr by observation. In such cases the battery commander's observer is provided with pad, pencil, and stop watch. FIRE DIRECTION— MINOR ARMAMENT. 33 The procedure is the same as when operating with a range finder, except in the following particulars: 1. The battery commander proceeds as in the normal system, except that he estimates the first range and the range increment. 2. The observer records and every five seconds calls the range to the range board operator. The range called differs from the preceding one by the amount of the range increment. (d) notes. 103. The spotting station will be located in such a position that the most accurate results of the observation of overs and shorts may be obtained. 104. A spotting station on the flank of the battery is especially desirable for night firing. 105. For night firing, if the target is well illuminated, the normal system will apply, but if the illumination is poor, the emergency system will be used. _ 106. Ammunition provided with the Semple tracer is of material aid to the battery commander in deciding when he is on the target. The use of a tracer at night provides the same facility for determin- ing the deflection corrections as now obtains in day practice. The same reliance, however, can not be placed on the estimates of overs and shorts from the battery as by day. 107. Sheaf ranging is preferable for night and emergency firing, and for day firing if the spotting station is well on the flank. 108. Where permanent installation is not provided, one or more battery commander's stations will be improvised at suitable places on the flanks of the battery. 109. Deflection and range boards as described in paragraphs 386 and 395 will be improvised until standard boards are supplied. Where no mechanical transmission devices are installed, they will be improvised, if practicable. If not practicable, telephone or other means of communication will be used. 104227°— 17 3 36 12-INCH MORTAR DRILL. 12-inch mortar drill. DeUils. At command DETAILS, POSTS. At command EXAMINE GUN. Chief of detaoh- inent (nonoommis- sioned ofiBcer). The chief of detachment takes post where he can super- vise the mortar detachment. The chief of detachment makes a careful inspection of the mortar and carriage and reports to the pit com- mander. Azimuth setter (noncommissioned officer or private). The azimuth setter takes post at the traversing cranks, facing the mortar. The azimuth setter exam- ines the azimuth index for adjustment by observing the mark made on the raoer when the piece was last ori- ented, and examines and tests the traversing mecha- nism. Elevation setter (noncommissioned oflioer or private). The elevation setter takes post at the quadrant or eleva- tion pointer, facing it. The elevation setter exam- ines the quadrant and tests the elevating mechanism, assisted by No. 5. 12-INCH MOBTAE BRlLl. 12-mch mortar drill. 37 .\.t command LOAD. The olilef of detachment super- vises the work of his detachment , assists in ramming the projectile, verifies the laying of the piece in azimuth and elevation, and calling " NO READY,'* takes cover after all of his detachment have taken cover. If his detachment is ordered to take cover before the giece is laid, he cuts it out of the ring circuit by opening the proper switch or by causing No. 2 to quit the lanyard when firmg by lanyard. He observes the muzzle of his mortar when a salvo is fired, and in case of a misfire calls out NO UISFIRE. At command RELAY. The chief of detach- ment's duties are the same as at the com- mand LOAD. At command CEASE FIR- ING. (When dummy ammu- nition is used.) The chief of de- tachment super- vises the work of his detachment. The azimuth setter takes post at a run and traverses the piece rapidly to the nearest limit of the loading position, as indicated by a paint mark on the iron portion of the azi- muth circle. He assists in ramming the projectile. He then traverses the piece as rapidly as possible to the azimuth setting posted. The azimuth setter returns to the piece at a run and sets the piece for the new azi- muth, and takes cover. The azimuth set- ter traverses the J)iece to the near- est limit of the loading position, and assists in ex- tracting the pro- jectile. The elevation setter takes post at a run, unclamps and depresses the piece to the loading position as rapidly as possible, but without shock, and sees that the spring latchis engaged. He sets the quad- rant for the elevation as soon as it is posted, and assisted by No. 5 ele- vates rapidly to the approximate elevation. Then he sets the piece accurately, clamps it, and takes cover. The elevation setter retm-ns to the piece at a run and lays the piece for the new eleva^ tion, clamps it, and takes cover. T h e elevation setter returns to the piece and pro- ceeds as at the command LOAD, 40 12-INCH MORTAR DRILL 12-inch mortar drill — Continued. Details. At command DETAILS, POSTS. At command EXAMINE GTTN. Elevating detail, No. 5. No. 5 takes post at Ihe ele- vating wheel, facing it. No. 5 removes the muzzle cover and places it at the designated place, assists the elevation setter in testing elevating mechanism, cleans and oils the gear. Powder - serving detail, No. fi. No. 6 procures a wrench for filling plugs, a measure con- taining hydrolene oil, and a funnel, and places them con- venient to the piece. He then takes post near the en- trance to the powder magar 2iue. No. 6 unscrews the filling plugs of both recoil cylinders and It oU is needed, fills them. Then he notifies the chief of detachment that the cylinders are ready for in- spection. After the inspec- tion he screws the filling plugs well home and re- places his implements. Truck details, Nos. 7, 8, 9, and 10. Nos. 7 and 8 bring out a loaded truck and ruii it to a point about 10 feet in rear of the breech, No. 7 on the right and No. 8 on the left. Nos . 9 and ID run an empty truck alongside the delivery table in the shot gallery, No. 9 on the right and No. 10 on the left. Nos. 7 and R, 9 and 10, ex- amine the trucks and clean and oil them. 12-lNCH MORTAR DRILL. 12-inch mortar drill — Continued. 41 At command LOAD. At command BELAY. At command CEASE FIR- ING. (When dunmiy ammu- nition is used.) No. 6 runs to the elevating hand- wheel, and at the command ELE- VATE, elevates rapidly to the ap- proximate elevation and takes cover. No. 5 returns to the piece at a run, elevates under direction of the elevation setter, and takes cover. II the command DRAW POWDER CHAB.GE has been given also, he proceeds as at the command COM- MENCE FIRING, and takes cover as soon as the piece is again clamped in ele- vation. No. 5 returns to the piece and pro- ceeds as at the command COM- MENCE FIRING until the piece is clamped in the loading position. Xo. 6 receives the powder charge on a powder serving tray from a member of the ammunition detach- ment before leaving his cover post, and follows the truck to the breech. As soon as the truck has been re- moved, he inserts the tray into the breech recess, and as soon as the powder charge has been pushed mto the chamber by No. 1, he withdraws the tray and takes his post at a run, carrying the tray n-ith him. No. 6 remains at cover post except .when the command DRAW POWDER CHARGE has been given also, in which case he brings up the next charge and thrusts it in the cham- ber as soon as No. 2 has withdrawn the old one. He then receives the old charge from No. 2 and takes cover, turning over the old powder charge to a member of the ammu- nition detachment. No. 6 receives the powder charge from No. 2, and returns it to the ammuni- tion detachment. Nos. 7 and 8 (or 9 and 10) run a truck from the position of cover to the loading position (about ten feet in rear of the breech) and 9 and 10 (or 7 and 8) run a loaded truck from the gallery to the position of cover just vacated by 7 and 8 (or 9 and 10). At the proper time 7 and 8 (or 9 and 10) push the truck for- ward rapidJy and bring i t up against the face of the breech without shock, timing their arrival at the breech so as to clear the block as it is swung to open. As soon as the projectile has been rammed, they withdraw the truck promptly and run it back- ward into the shot gallery and alongside of the delivery table, roll a new projectile on the truck, and at the next sliot run the reloaded truck rapidly to the position of cover just vacated by 9 and 10 (or 7 and 8), who have pushed their truck forward to the loading posi- tion. No duties. Nos. 7 and 8 (or 9 and 10) biing out empty truck from the gallery and when projectile is drawn back onto the truck return it to the gallery. 44 12-lNCH MORTAR DRILl. NOTES ON THE DRILL. 121. At the command TAKE COVER, the mortar detachments take positions in rear of the pit, arranged in order from the right (No. 1 detachment on the right). Each detachment is in double column, as follows: Elevation setter. Azimuth setter. (or 10) 8 7 (or 9) 11 122. The cover post for No. 4 is the same as his regular post, and the detachment forms on him at the command TAKE COVER. Ttle does not quit the rammer except at the command CEASE FIRING, or when directed to do so, in which cases he places the rammer on the rack or prop. 123. When powder is not served from the rear of the pit, the cover post of No. G is near the entrance of the gallery from which powder is served. 124. In taking cover, the details proceed to their posts as rapidly as possible, but should avoid interfering with those whose duties at the piece have not been completed. 125. The service of the mortar is conducted habitually as though a salvo had just been fired (pieces elevated and detachments at cover post), but in case the command COMMENCE FIRING or LOAD is given when the details are at their posts and the pieces in the loading position, No. 6 proceeds at a run to the point designated for receipt of the powder charge. 126. When mortars are equipped for firing by electricity, they are fired by the emplacement officer at the signal of the battery commander. Mortars are fired by lanyard if the electrical firing circuit is not installed or is out of order. When the lanyard is used, the emplacement officer commands FIRE at the firing signal of the battery commander. 127. The chief of ammunition is in command of the ammunition detachment, and has charge, under the pit commander, of the galleries and magazines pertaining to his emplacement. 12-INCH MOKTAR DRILL 45 He is reBponsible for the condition of tlie projectiles, troUeys, delivery tables and for the police of the galleries and magazines. When the details are posted, he makes an inspection of the trolleys, magazines, and galleries and reports to the pit commander "Ammunition service in order," or reports defects he is unable to remedy without delay. He is responsible tliat all trucks are loaded and delivery tables filled with projectiles at the beginning of an action. Dunng drill or action he supervises the service of ammimition. 48 12 OB 14INCH GUN DBILL. 12 or 14 inch gun drill {disappearing carriage). Details. At command DETAILS, POSTS. At command EXAMINE GUN. Gun coirunandor (noncommissioned officer). The gtm commander gives the command DETAILS, POSTS and supervises the procuring of equipment and implements. He posts the reserve detachmenf. The gun commander gives the command EXAMINE GTTN, makes a general in- spection of the gun and car- nage, and reports to the em- placement officer. (.innpoiiiter(non~ commissionerl ofli- ccr or private). The gun pointer procures the sight, places it in its seat, and takes post on the sighting platform. The gun pointer examines the sight and verifies the ad- justment of the azimuth index. He examines the traversing mechanism and the electric ffi-ing mech- anism and circuit (i^ used). Range setter C noncoihmissioned olllcer or private). The range setter takes post facing the range scale. The range setter examines the elevatmg and retracting mechanisms, and cleans and oils the gears if necessary. Range recorder ( noncommissioned oflicor or private). The range recorder pro- cures chalk, a ruler, a black- board eraser, and a stop watch, and takes post at the time-range board. The ran^e recorder exam- ines the time-range board. He puts on the head set and tests the telephone to the plotting room. Deflection re- corder (noncom- missioned officer or private). The deflection recorder pro- cures chalk, and a blackboard eraser, and takes post at the deflection recorder's board. The deflection recorder examines the deflection re- corder's board. He puts on the head set and tests the telephone to the plotting room. 12 OR 14 IKCH GUN SBIIL. 12 or 14- inch gun drill {disappearing carriage). 49 At command LOAD. At command CEASE FIR- ING (when dummy am- munition is used). Tte gun commander gives the command LOAD and supervises the work of his section. After the chief of breech has given the command TKIP, the gun commander sees that the gun goes fully into battery, veriBes the range settmg, and if the set- ting is correct, calls READY. The gun commander gives the command CEASE FIR- IITG and supervises the work of unloading. The gun pointer sets the deflection recorded on the deflection recorder's board and directs the traversing so that he will be on the target by the time the gun is in battery. He fires the piece or gives the command i'lKE as soon after the com- mand HEADY as the piece is pointed. No duties. At the command TRIP the range setter lavs the piece for range in accordance with information obtained from the time-range board, as described in Par. 400. No duties. The range recorder continues plotting the time- range curve as prescribed in Par. 400. The range recorder con- tinues plotting the time- range curve. The deflection recorder makes a record of the last deflection received when it diflers from the last one recorded, erasing the latter. The deflection recorder continues recording deflec- tions. 50 12 OR 14 INCH GUN BRILL. n or 14 inch gun drill {disappearing carriage) — Continued. Details. At command DETAILS, At command EXAMINE POSTS. GTJN. Breech detail, chiel of tireecli (riojiconimissioncd officer or private), and Nos. 1, 2, 3, and 21. The chief of brooch takes post 2 yards in rear of the breech, facing it. No. 1 procures a -wiper or cotton ■waste and a can con- taining lubricating oil and a sponge. He places the can convenient to the breech and takes post about 1 yard to the rear and right of the breech, lacing it. No. 2 procures the operat- ing crank for the breech mechanism and places it in position. He also procures a wiper or cotton -waste and takes post about 1 yard to the rear and left of the breech, facing it. No. 3 procures the lanyard (if one is used), primers, primer pouch, punch, drill, reamer, and flruig mechan- ism, and takes post on the right side of the piece about 1 foot to the right and front of the elevating band, facing to the rear. No. 21 takes post ahout 2 feet to the right of the breech on line -with its face, facing it. (Note.— For 14-inch guns the distances of Nos. 1, 2, 3, and 21 from the breech may be increased. The chief of breech exam- ines the breech mechanism, breechblock, breech recess, chamber, and bore, and gives the necessary orders for cleaning and putting them into condition for service. Nos. 1 and 21 remove the breech cover and place it at the designated place. They clean and oil the breech- block and breech mechan- ism. No. 2 cleans and oils the breech recess and gas check seat. No. 3 examines the vent and the firing mechanism. He clears the vent and cleans the primer seat. Ho coils the long lanyard (if one is U3ed)and hangs it overthc end of the elevating arm. Rammer detail, Nos. 4, 22, and 23. Nos. 4 and 22 procure the rammer and place it on the hooks near the rail, head toward the hoist. No. 4 takes post about 2 yards from the head of the rammer, -within reach of the stall, facing the piece. No. 22 takes post 4 yards to the left of No. 4, facing the piece. No. 23 procures the ex- tractor for the dummy pro- jectile and places it near the rammer, takes post 4 yards to the right of No. i, facing the piece. No. 4 assists the breech detail in cleaning -when necessary. No. 22 removes the muzzle cover, hands it to No. 8, -who places it at the designated place. No. 23 assists No. 9 in ai- ing the recoil cylinders, pass- ing up the oil measure and the funnel when needed. Elevating detail, Nos. 5 and 6. Nos. S and 6 take posts at the elevating hand-wheel on the same side as the range setter, facing the piece. Nos. 5 and 6 assist the range setter in examining the elevating and retracting mechanism, and in cleaning and oiling the gears. - - - - ' ^-^^ = ^- L. . „ 12 OB 14 INCH GUN BRIXL. 61 12 or 14 iitth gun drill {disappearing carriage) — Continued. At command LOAD. At command CEASE FIR- , ING. (When dummy am- I munition is used.) The chief o! breech gives the command HOME RAU for ramming the projectile, and the com- mand IS BATTEKT, TRIP for tripping the gun. If a lanyard is used, he hooks the lanyard before the primer is inserted, and does not com- mand TRIP until after the primer is inserted. After firing, he unhooks the lanyard. No: 1 places the head of the rammer against the base of the projectile as the truck approaches the breech, assists in ranmiing the projectile, closes breech, assisted by No. 2, and goes to his place on the rammer and stands by for the next snot. After each shot No. 2 wipes off the mushroom head and gas-check seat, then takes his place on the rammer, assists in ramming the projectile, and assists No. 1 in closing breech. No. 3 inserts a primer after the breechblock is completely closed and lowers the leaf of the firing device completely down, steps back to the rear as the gun goes in battery, lettmghis lanyard (if one is used) uncoil, and pulls the lanyard (if one is used) at the command FIRE. After the piece is fired he coils the long lanyard (if a lanyard is used) and as soon as the breech is opened removes the old primer, clears the vent, and cleans the primer seat. No. 21 opens the breech and cleans and oils the breechblo<* when necessary. He assists No. 1 with the crank when there is difficulty in closing the breech. If the projectile fails to seat at the first trial, he assists on the rammer. Note.-— (The battery commander may require Nos. 1 and 2 to assist in ramming the powder, and the chief of breech to assist In ramming the projectile.) The chief of breech super- VLses unloading. Nos. 1 and 2 assist in with- drawing the dummy powder charge and the dummy pro- jectile. No. 3 removes the primer. No. 21 opens breech and assists in withdrawing the dummy projectile. The truck is brought up to the face of the breech, and the projectile pushed carefully ofT the truck until the bsise of the projectile is just inside the powder chamber. The truck is then withdrawn and run off to one side. Nos. 1, 2, 4, 9, 10, 21, 22. and 23 then man the rammer as near the outer end as possible, and at the command HOME RAM by the chief of breech, they rush the projectile for- ward hard into its seat, increasing the si»ed of the rush so that the projectile will have its fastest movement when it comes up hard in its seat. The rammer detail pushes the powder off the powder tray and into the powder chamber to such a dis- tance that the breechblock will give the powder charge a final push into the chamber in closing. NotE. — (The battery commander may require Nos. 1, 2, 9, and 10 to assist in ramming the pow- der, and the chief of breech to assist in ramming the projectile.) No. 4 brings up the ex- tractor and pulls the dummy fiowder sections back onto he tray. He hooks the ex- tractor into the dummy pro- jectile and assists in with- drawing it. Nos. 22 and 23 assist in withdrawing the dummy projectile. Nos. 5 and 6 elevate or depress the piece under jlirection ol the range setter. No duties. 52 12 OR 14 INCH GUN DRILL. 12 or 14 inch gun drill {disappearing carriage) — Continued. At command DETAILS, POSTS. At command EXAMINE GUN. Traversing detail, Nos. 7 and 8. Nos. 7 and 8 procure the traversing cranks, place one of them on the shaft, on the same side as the gun pointer, and talce posts at the cranic iicing to tne rear. Nos. 7 and 8 remove the drip pans, assist in testing the traversing mechanism. No. 8 receives the muzzle cover from No. 22 and places it at a designated place. Tripping detail, Nos. 9 and 10. No. 9 procures a -wrench for filling plugs, a measure con- taining hydrolene oil, and a funnel, and goes to the right tripping lever. No. 10 procures a -wrench for filling plugs and goes to the left tripping lever. Nos. 9 and lOmount on the chassis, each carrying a •wrench, and remove the filling plugs from the recoil cylinders. If oil is needed. No. 9 calls on No. 23 for the funnel and measure, and pours oil into the right cyl- mder slowly. No. 10 watches the oil hole in the left cylinder. When hoth cylinders are full. No. 9 hands the funnel and meas- ure back to No. 23 and noti- fies the gun commander that the cylinders are ready for inspection. After the inspection, Nos. 9 and 10 screw the plugs well home, and take posts facing the piece hy the platform rail- mg. No. 9 three yards to the right of No. 4, and No. 10 three yaids to the left of No. 4. Truck detail, Nos. 11 and 12. Nos. 11 and 12 bring outthe shot trucks to be used and take posts at the handles ot one 01 the trucks — No. 11 on the right and No. 12 on the left. Nos. 11 and 12 examine the trucks and clean and oil them when necessary. They then turn them over to the hoist detail for load- ing. When the fii'st tnlek is loaded, they push it out to some convenient position in rear of the breech. Towder serving detail, Nos. 13, 14, 15, and 16. Nos. 13, 14, 1.3, and 16 bring out the powder trays to be used and turn them over to the ammunition detachment. They take pqsts opposite the first tray loaded, Nos. 13 and 15 on the right and Nos. 14 and 16 on the left, Nos. 13 and 14 in rear. Nos. 13, 14, 15, and 16 see that the powder sections are arranged on the trays in the order in which they are to be inserted. Hoist detail, Nos. 17, 18, and 19. No. 17 is chief of detail unless a noncom- missioned officer is assigned in charge. Nos. 17, 18, and 19 take posts at the delivery table. Nos. 17, 18, and 19 exam- ine and clean the delivery table and the projectiles on it. They examine the auto- matic stop. They load the trucks turned over to them by the truck -detail. 12 OR 14 INCH GUN DRILl. 53 f or 14 inch gun drill {disappeariri^f carriage)— Gontmued. At command LOAD. At command CEASE FIR- ING. (When dummy am- munition is used.) Nos. 7 and 8 traverse the piece under direction of the gun pointer. They halt when the piece is fired and resume traversing as soon as the truck is withdrawn from the breech. No duties. Nos. 9 and 10 assist in ramming the projectile. As soon as the projectile is seated they quit the rammer and run to the tripping levers. At the command IIT BATTERY they seize the tripping levers and at the commimd TRIP raise them quickly to the stops, hold them for an instant, then let go, and -whea the gun is in battery nin back to their posts at the rammer, where they stand by for the next shot. If firing by electricitj-, No. 9 (or No. 10) closes the safety sw'itch as soon as the gun is in battery. Note. — (The battery commander may require Nos. 9 and 10 to assist in ramming the powder.) No duties unless the dummy projectile sticks, in which case they assist in starting it from its seat. Nos. 11 and 12 run out a loaded shot truck, No. 12 adjusting the truck to the proper height in ac- cordance with the position of the piece upon recoil. The truck is run forward so that the tray enters the breech recess squarely. As the truck brings up against the iSLce of the breech No. 12 sets the brake. As soon as the projectile is pushed off the truck Nos. 11 and 12 run the truck back to the hoist and turn it over to the hoist detail. They then take posts behind a loaded truck and stand by for the next shot. Nos. 11 and 12 push a truck into position at the breech to receive the dummy projec- tile and then return the truck to the loading position. As soon as the rammer has been withdrawn after seating the projectile the nose of the powder tray is inserted in the breech by Nos. 13, 14, 15, and 16, and the rammer detail, in one motion, pushes carefullj^ the entire powder charge off the tray to such a distance that the breech block will give the powder charge a final push into the chamber in closing. The tray is then removed and the breech closed. Nos. 13, 14, 15, and 16brmg up an empty powder tray to receive the dummy powder sections and return the loaded tray to the loading position. Nos. 17, 18, and 19 receive the empty truck after each shot, load it, and run it out conveniently for Nos. 11 and 12. No duties. 54 12 OR 14 INCH GUN BBIIL. 12 OT 14 inch gun drill (disappearing carriage) — Continued. Details. At command DETAILS, POSTS. At command EXAMINE GUN. Sponge detail, No. 20. No. 20 prociures the cham- ber sponge and a vessel con- taining liquid for sponging, places them on the opposite side of the emplacement from the rammer, and takes post near the chamber sponge, fac- ing the gxm. (If there is to be no firing, the vessel may be empty.) No. 20 brings up the chamber sponge when called for and assists in sponging the chamber. 12 OR 14 INCH GUN DRIll,. 65 12 or 14 inch gun drill (disappearing carriage) — Continued. At command LOAD. At command CEASE FIK- ING. (When dummy am- munition is used-) No. 20 dips the chamber sponge in the liquid lor sponging and allows the excess liquid to run oft as . soon as the breech bloclc is opened after each shot; assisted by the breech detail, he sponges the cham- ber as qviickly as practicable. No duties. ( a C.A.D. R. Nos. 2ande.) 66 12 OR 14 INCH GUN DRILL. NOTES ON THE DRILL. (See also Chapters V, XV, XVI, and XXI.) 137. The service of the piece as given above is for a gun with an 1895 breech mechaniam. If the gun has an 1888 breech mech- anism, the duties of the breech detail differ in the following re- spects: No. 1 assists in opening the breechblock, oils the threads, and assists in closing the breech; No. 21 assists on the translating crank, if necessary. 138. To open breech, model 1888 mechanism. — No. 2 releases the rotating crank by turning the wing nut of the catch to the left and then turns the rotating crank clockwise, as indicated by the "open" arrow, until it brings up short in a horizontal position and is secured by its catch; No. 1 turns the translating crank briskly contraclock- wise. When the shoulders of the grooves strike against the ends of the i-ails, the block stops short and the shock frees the tray latch from its catch; No. 1 swings the tray and block to the right until the securing latch engages in the catch. 139. To close breech, model 1888 mechanism. — No. 2 releases the seciu'ing latch from its catch; No. 1 swings the tray and block around to the left smartly; No. 2 seizes the handle of the tray and continues the swinging of the block until the tray abuts against and is latched to the face of the breech; then he turns the translating crank clockwise until the breech is translated completely; No. 1 releases the rotating crank by turning the wing nut and turns the rotating crank contraclockwtse, as indicated by the "close" arrow, until it brings up short in a vertical position and is secured by its catch. 140. To open breech, model 1895 mechanism. — The chief of breech unhooks the lanyard (when one is used) from the eye of the firing leaf; No. 21 turns the crank continuously in a clockwise direction until the tray comes to a rest against the hinge plate and the securing latch catches. 141. To close breech, model 1895 mechanism. — No. 1 releases the securing latch and turns the crank in a contraclockwise direc- tion until the projecting shoulder on the rotating lug striking the gear prevents further motion. The latch is released before the truck is withdrawn from the breech, holding the breechblock open by the operating crank until time to close it. 142. With the 1895 breech mechanism it will be convenient to fasten a wire around the piece back of the elevating band with a loop in which the safety lanyard (Lf a lanyard is used) may be hooked during the loading. The chief of breach after unhooking the lanyard swings it over the teeth of the breech mechanism and hooks it in the loop of the wire. Thus it is kept from being caught in the mechanism and is convenient to the chief of breech when the time comes to hook it again. 143. Prior to practice or action shot trucks are adjusted to the highest point to which it is anticipated the gun will recoil, since the adjustment is made downward more easily and rapidly than upward. 12 OS 14 INCH GVN DEILL. 57 144. If tlie gun fails to go in battery completely, the gun com- mander orders Nob. 9, 10, 22, and 23 to use the pinch bars; these are engaged in the notches on the chassis and the gim is forced into battery. However, battery commanders mil observe such defects at daily drill and will have the same remedied before practice or action. 145. To retract the gun. — Assuming that the gun is in battery, that the clutch is out, and that the cables are wound on the retraction drums, to retract the gun by hand the gun commander wiU com- mand (1) FROM BATTEBY, (2) HEAVE, (3) HALT. At the firs.,; command No. 7 releases the retaining pawl and turns the speed crank to permit the pulling out of the cables. Nos. 1 and 2 pull out the cables to their full length and pass the ends to Nos. 21 and 4, who will have moimted on the chassis. Nos. 21 and 4 pass the cables to Nos. 9 and 10, who will have mounted the gun levers, and who will place the ends of the cables on the hooks. No. 7 will then throw on the retaining pawl and will turn the speed crank to take up all slack, and No. 8 will push in the clutch, Nos. 21 and 4 watch- ing the cables to see that they take the gixioves of the drums. A.s soon as the slack has been taken up Nos. 4, 21, 9, and 10 return to the loading platform and Nos. 7 and 8 put on the retraction cranks. The gun section is divided into two reliefs by the gim commander. The first relief takes post at the retraction cranks, and at the second command start to retract the gun. The reliefs alternate as directed by the gun commander. As soon as tlie crosshead teeth engage their pawls the retraction shaft retaining pawl is thrown off, and remains oft until the cables have been unhooked from the gun levers. When the gun has reached the loading position the gun com- mander commands HALT. At this command Nos. 7 and 8 remove the retraction cranks. No. 7, using the speed crank, lets out enough slack to enable Nos. 1 and 2 to unhook the cables. After the un- hooking No. 7 takes up aU slack with the speed crank asnd then throws the retaining pawl on. No. 8 then puUs out the clutch. 146. For retraction by power the above drill is modified as follows: Assuming the idler to be out of gear, after the cables have been hooked to the gun levers and the slack has been taken up by No. 7 and the clutch thrown in by No. 8, at the csmmand HEAVE by the gun commander. No. 8 throws the idler in gear. . As soon as this is done the range setter closes the main, switch of the con- troller cabinet and moves the arm so as to turn on the power. The movements at the command HALT are the same as those prescribed for hand retraction, except that the range setter puUs the main switch of the controller cabinet, after which No. 8 throws the idler out of gear. The! cables are then unhooked, and the slack taken up as described for hand retraction. 147. On carriages equipped with &iction brakes on the retraction crank shaft it is not necessary to unhook the cables from the gun levers. The time consumed in pulling out and hooking the cables is thereby saved. On carriages so equipped the cables need not be unhooked, and the drill may be modified accordingly. Chapter IX. 8 OR 10 mCH GUN DBILL (DISAPPEABING CABBUGE). THE GXrS SECTION. 148. Each emplacement is manned by a gun section (37 enlisted men plus the reserve detachment) consisting of a gun detachment, an ammunition detachment, and a reserve detachment. The gun commander is in command of the gun section, and is also chief of the gun detachment. 149. The gun detachment (26 enUsted men) consists of the gun commander, the gun pointer, the chief of breech, the range setter, the range recorder, the deflection recorder and 20 cannoneers numbered from 1 to 20, inclusive. The gun detachment ia divided into details as shown in the drill which follows. 150. The ammunition detachment (11 enlisted men) consists of the chief of ammunition and 10 cannoneera, numbered from 21 to 30, inclusive. The ammunition detachment is divided into details for the service of powder and projectiles according to the location of magazines, shot rooms, and hoists pertaining to the emplacement. 151. The reserve detachment consists of all unassigned can- noneers. It is divided into two reserve details, one for the gun detachment and one for the ammunition detachment. The reserve detacliment is posted by the gun. commander at some convenient place or places, and is used by him to fill vacancies in the other detachments. 158. To post the gun section. — ^The section is posted as prescribed in detail in paragraph 40. The gun commander commands DETAILS, POSTS, and after the caimoneers are posted, he com- mands EXAMINE GUN. 153. To call off. — The battery coromander may at any time give the command CALL OFF, whichis repeated by the gun commander. The cannoneers call off their numbers, beginning at one. 154. To load and fire. — The battery commander indicates the target as prescribed in Chapter V. He designates the kind of pro- jectile to be used, and after tracking has begun, commands: (o) COMMENCE FIEING. (6) FIRE BOUNDS, COMMENCE FIBINQ. (c) NUMBEB(S) FERE SHOTS, COMMENCE FIRING. The gun commander commands LOAD when the batteiy com- mander gives the command COMMENCE FIRING, and before each shot of a series. The battery commander may give the command LOAD, in which case the gun commander repeats the command. The piece 8 OS 10 INCH OTTN SRILI. 69 is loaded but is held from battery until the battery commander commands COMMENCE FIRING. When the number of rounds specified has been fired, the gun commander commands CEASE FIRING, at which command all cannoneers resume their posts. When the number of rounds is not specified, the battery com- mander commands CEASE FIRING, and the gun commander repeats the command. 155. When dummy ammunition is used, the piece is imloaded at the command, CEASE FIRING, unless otherwise ordered. 166. The following drill is prescribed: 60 8 OB 10 INCH GTJN DRILL. 8 or 10 inch gun drill {disappearing carriage). Details. At command DETAILS, POSTS. At command EXAMINE GTTN. Gun commander (noncommissioned oinoer). The gun commander gives the command DETAILS, POSTS and supervises the procuring of equipments and implements. He posts the re- serve detachment The gun commander gives the command EXAMINE GUN, makes a general in- spection of the gun and car- riage and reports to the em- placement officer. Gun pointer (noncommissioned officer or private). The gun pointer procures the sight and places it in its seat and takes post on the sighting platform. The gun pointer examines the sight and verifies the ad- justment of the azimuth in- dex. He examines the trav- ersing mechanism and the electric firing mechanism and circuit (if used). Range setter (noncommissioned officer or private). The range setter takes post facing the range scale. The range setter examines the elevating and retracting mechanisms. He cleans and oils the gears. Range recorder (noncommissioned officer or private). The range reoorderprocures chalk, a ruler, a blackboard eraser, and a stop vratch and takes post at the time-range board. The range recorder exam- ines the time-range board. He puts on the head set and tests the telephone to the plotting room. Deflection recor- der (noncommis- sioned officer or pri- vate). The deflection recorder pro- cm-es chalk and a blackboard eraser, and takes post at the deflection recorder's board. The deflection recorder ex- amines the deflection recor- der's board. He puts on the head set, and tests the tele- phone to the plotting room. Breecli detail, chief of breecli (noncommissioned officer or private), and Nos. 1, 2, and 3. The chief of breech takes post 2 yards in rear of the breech, facing it. No. 1 procures a wiper or cotton waste and a can con- taining lubricating oU and a sponge. He places the can convenient to the breech and takes post about 1 yard to the rear and right of the breech, facing it. No. 2 procures the operat- ing crank for the breech mechanism and places it in position. He also procures a wiper or cotton waste and takes post about 1 yard to the rear and left of the breech, facing it. No. 3 procures the lanyard (when one is used), primers, primer pouch, punch, drill, reamer, and firmg mechan- ism, and takes post on the right side of the piece, about 1 foot to the right and front of the elevating band, facing to the rear. The chief of breech exam- ines the breech mechanism, breechblock, breech recess, chamber, and bore, and gives the necessary orders lor cleaning and putting them into condition for service. No. 1 removes the breech cover and places it at the designated place. He cleans and oils the breechblock and breech mechanism. No. 2 cleans and oils the brooch recess and gas check seat. No. 3 examines the vent and the firing mechanism. He clears the vent and cleans the primer seat. He coils the long lanyard (if one is used) and hangs it over the end of the elevating arm. 8 OR 10 INCH GUN DRILL. 8 or 10 inch gun drill {disappearing carricge). 61 At command LOAD. At command CEASE FIR- ING (when dummy am- munition is used). The gun commander gives the command LOAD and supervises the work of his section. After the chief of breech has given the command TKIP, the gun commander sees that the eon goes fully into battery, verifies the range settmg, and if the setting is correct, calls READY. The gun commander gives the command CEASE iXH- ING, and supervises the work of unloading. The gun pointer sets the deflection racorded on the deflection recorder's board and directs the traversing so that he will be on the target by the time the gun is in battery. He fires the piece or gives the command FERE as soon alter the com- mand BKAD7 as the piece is pointed. No duties. At the command TRIP the range setter lays the piece for range in accordance with information ob- tained from the time-range board as prescribed in par. 400. No duties. The range recorder continues plotting the time- 1 The range recorder con- range curve, as prescribed in par. 400. j tinues plotting the time- ! range curve. I The deflection recorder makes a record of the last deflection received when it differs from the last one recorded, erasing the latter. The deflection recorder con- tinues recording deflections. The chief of breech gives the command HOME RAH for ramming the projectile, and the com- mand IW BATTERY TRIP for tripping the gun. If a lanyard is used, he hooks the lanyard before the primer is inserted, and does not com- mand TRIP until after the primer is inserted. After firing he mihooks the lanyard. Nos. 1 and 2 open the breech. No. 1 places the head of the rammer against the base of file projectile as the truck approaches the breech, assists in ramming the projectile, and closes breech, assisted by No. 2. After each shot No. 2 wipes off the mushroom head and gas-check seat, then takes his place on the rammer, assists in ramming the projectile, and assists No. 1 in closing the breech. No. 3 inserts a primer after the breechblock is completely closedand lowers the leaf of the fixing device completely dowUf steps back to the right and rear as the gun goes in battery, letting his lanyard (if one is used) uncoil. He pulls the lan- yard (if one is used) at the command i^lRE. Af- ter the piece is fired he colls the long lanyard (if a lanyard is used), and as soon as the breech is opened removes the old primer, clears the vent, and cleans the primer seal;. Note.— (The battery commander may require Nos. 1 and 2 to assist in ramming the powder, and the chief of breech to assist in rammmg the pro- jectile.) The chief of breech super- vises unloading. Nos. 1 and 2 assist in withdrawing the dummy powder charge and the dummy projectile. No. 3 removes the primer. 62 8 OR 10 INCH GUN DRILL. 8 or 10 inch gun drill {disappearing carriage) — Continued. Details. At command DETAILS, POSTS. At command EXAMrCTE GTTN. Rammer detail, No. 4. No. 4 procures the rammer and places it on its hooks near the rail, head toward the hoist. He procures the ex- tractor for the dummy pro- jectile and places it near the rammer. He takes post about 2 yards from the head of the rammer, within reach of the staff, feeing the piece. No. 4 assists the breech detail in cleaning when nec- essary. Elevating detail, Nos. 5 and 6. Nofi. 5 and 6 take posts at the elevating handwheel on the same side as the range setter, facing the piece. Nos. 5 and 6 assist the range setter in examining the elevating and retracting mechanism and in cleaning and oiling the gears. Traversing de- tail, Nos. 7 and 8. Nos. 7 and 8 procure the traversing cranks, place one of them on the shaft on the same side as the giui pointer, and take posts at the crank, facing to the rear. Nos. 7 and 8 remove the drip pans and test the trav- ersmg mechanism. No. S receives the muzzle cover from No. 11 and places it at a designated place. Tripping detail, Nos. 9 and 10. No. 9 procures a ■wrench for filling plugs, a measure con- taining hydrolene oil, and a funnel, and goes to the right tripping lever. No. 10 procures a wrench for filling plugs and goes to the left tripping lever. Nos. 9 and 10 mount on the chassis, each carrying a wrench, and remove the filling plugs from the recoil cylinders. If oil is needed, No. 9 calls on No. 11 for the fiuuiel and measure and pours oil into the right cyi- mder slowly. No. 10 watches the oil hole in the left cylinder. When both cylinders are full, No. 9 liands the funnel and meas- ure back to No. 11 and noti- fies the gim commander that the cylinders are ready for inspection. After the in- spection, Nos. 9 and 10 screw the plugs well home and take posts, facing the piece, by fhe platform rail- ing. No. 9 one yard to the right of No. 4 and No. 10 one yard to the left of No. 4. 8 OR 10 INCH GUH DRILL. 63 8 or 10 inch gun drill (disappearing carriage) — Continued. At command LOAD. At command CEASE FIR- ING. (When dummy am- munition is used.) The truck is brought up to the face of the breech and the projectile pushed carefully off the truck until the base of the projectile is just inside the powder chamber. The truck is then withdrawn and run oS to one side. Nos. 1, 2, 4, 9, and 10 then man the rammer as near the outer end as possible, and at the command HOME BAM by the chief of breech they rush the projectUe forward hard mto its seat, mereasing the speed of the rush so that the projectile will have its fastest movement when it comes up hard in its seat. The rammer detail pushes the powder off the powder tray and into the powder chamber to such a distance that tha breechblock will give the powder charge a final push into the chamber in closing. Note.— (The battery commander may require Nos. 1 and 2 to assist in ramming the powder, and the chief of breech to assist in ramming the pro- jectile.) No. 4 brmgs up the extrac- tor and pulls the dummy powder sections back onto the powder tray. He hooks the extractor into the dummy projectile and assists in withdrawing it. Nos. 5 and 6 elevate or depress the piece under direction of the range setter. No duties. Nos. 7 and 8 traverse the piece under direction of the gun pointer. They halt when the piece is fired and resume traversing as soon as the truck is withdrawn from the breecE No duties. Nos. 9 and 10 assist in ramming the projectile. As soon as the projectile is seated they quit the rammer and run to the tripping levers. At the command IS BATTERY they seize the tripping levers, and at the command TKIP, raise them quickly to the stops, hold them for an instant, then let go, and when the gun is in battery run back to their posts at the rammer, where they stand by for the next shot. If firing by electricity, No. B (or 10) closes the safety switch as soon as the gun is in battery. No duties imless the dum- my projectile sticks, in which case they assist in starting it from its seat. 64 8 OR 10 INCH GTTN DRILL. 8 or 10 inch gun drill {disappearing carriage) — Continued. Details. At command DETAILS, POSTS. At command EXAIIINE GUU. Truck detail, Nos. 11 and 12. Nos. 11 and 12 bring out the shot trucks to be used and take posts at the handles of one of the trucks; No. 11 on the right and No. 12 on the left. No. 11 removes the muz- zle cover, hands it to No. 8, and assists No. 9 in filling the recoil cylinders, passing up the oil measure and the funnel when needed. Nos. 11 and 12 examine the trucks, clean and oil them when necessary. They then turn them over to tnehoist detail for load- ing. When the first truck is loaded, they push it out to some convenient posi- tion in rear of the breech. Powder serving detail, Nos. 13, 14, 15, and 16. Nos. 13, 14, 15, and 16 bring out the powder trays to be used and turn them over to the ammunition detachment. They take posts opposite the first tray, loaded. Nos. 13 and 15 on the right and Nos. 14 and 16 on the lett; Nos. 13 and 14 in rear. Nos. 13, 14, 15, and 16 see that the powder sections are arranged on the trays in the order in which they are to be inserted. Hoist detail, Nos. 17, 18, and 19. No. 17 is chief of detail imless a noncom- missioned officer is assigned in charge. Nos. 17. 18, and 19 take posts at the delivery table. Nos. 17, 18, and 19 exam- ine and clean the delivery table and the projectiles on it. They examine the auto- matic stop. Tbey load the trucks turned over to them by the truck detail. Kponge detail, No. 20. No. 20 procures the cham- ber sponge and a vessel con- taining the liquid for spong- ing , places them near the raU- ing on the opposite side of the emplacement from the ram- mer, and takes post near the chamber spongBj facing the gun. (If there is to be no firmg, the vessel may be empty.) No. 20 brings up the cham- ber sponge when called for and assists in sponging the chamber. 8 OR 10 INCH GUN DRILI. 66 S or 10 inch gun drill (disappearing carriage) — Continued. At conunand LOAD. At command CEASE FIR- ING. (When dummy am- munition is used.) Nos. 11 and 12 run out a loaded stiot truck, No. 12 adjusting the truck to the proper height in ao- cordance with the position of the piece upon re- coil. The truck is run forward so that the tray enters the breech recess squarely. As the truck brings up agamst the face of the breech No. 12 sets the brake. As soon as the projectile is pushed off the truck Nos. 11 and 12 run the truck back to the hoist and tiun it over to the hoist detail. Then they take posts behind a loaded truck and stand by for the next shot. Nos. 11 and 12 push a truck into position at the breech lo receive the dummy pro- jectile, then return the truck to the loading position . As soon as the rammer has been withdrawn after seating the projectile, the nose of the powder tray is inserted in the breech by Nos. 13, 11, 15, and 16, and the rammer detail, in ore motion, pushes carefully the entire powder charge off the tray to such a distance that the breechblock will give the powder charge a final push into the cham- ber in closing. The tray is then removed and the breech closed. Nos. 13, 14, 15, and 16 bring up and empty powder tray to receive the dummy powder sections, and return the loaded tray to the loading position. Nos. 17, 18, and 19 receive the empty truck after each shot, load it, and run it out conveniently for Nos. 11 and 12. No duties. No. 20 dips the chamber sponge in the liquid for sponging and allows the excess liquid to run off. As soon as the breechblock is opened after each shot, assisted by the breech detail, he sponges the chamber as quickly as practicable. No duties. (C. C.A.D. R. Nos. I and 6.) NOTES ON THE DRILL. 157. Tte notes on the drill of the 12-inch or 14-inch gun battery, disappearing carriage, apply to an 8-inch or 10-inch gun battery, disappearing carriage, except that— (a) The duties prescribed for Nos. 22 and 23 are omitted. (6) The duties prescribed for No. 21 are omitted except those pertaining to retraction, ajid those prescribed in par. 140, which are performed by No. 3. 104227°— 17 5 Chapter X. 6-INCH GTTN DRILL (DISAPPEAKING CABEIAGE). THE GTJIT SECTION. 168. Each emplacement is manned by a gun section (22 enlisted men plus the reserve detachment) consisting of a gun detachment, an ammunition detachment, and a reserve detachment. The gun commander is in command of the gun section, and is also chief of the gun detachment. 159. The gun detachment (15 enlisted men) consists of the gun commander, the gun pointer, the range setter, the range recorder, the deflection recorder, and 10 cannoneers^ numbered from 1 to 10, inclusive. The gun detachment is divided into details as shown in the drill which follows. 160. The ammunition detachment (7 enlisted men) consists of the chief of ammunition and 6 cannoneers, numbered from 11 to 16, inclusive. The ammunition detachment is divided into de- tails for the service of powder and projectiles according to the loca- tion of magazines and shot rooms pertaining to the emplacement. 161. The reserve detachment consists of all unassigned can- noneers. It is divided into two reserve details, one for the gun detachment and one for the ammunition detachment. The re- serve detachment is posted by the gun commander at some con- venient place or places, and is used by him to fill vacancies in the other detachments. 162. To post the gun section. — ^The section is posted as prescribed in detail in paragraph 40. The gun commander commands DE- TAILS, POSTS, and after the cannoneers are posted he com- mands EXAMINE GUN. 163. To call off. — The battery commander may at any time give the command CALL OFF, which is repeated by the gun com- mander. The cannoneers call oft their numbers beginning at 1. 164. To load and fire. — The battery commander indicates the target as prescribed in Chapter V. He designates the kind of pro- jectile to be used, and after tracking has begun commands: (a) COMMENCE FHtlNG. (b) FIBE BOUNDS, COMMENCE FIRING. (c) NUMBER(S) FIRE SHOTS, COMMENCE FIRING. The gun commander commands LOAD when the battery com- mander gives the command COMMENCE FIRING, and before each shot of a series. The battery commander may give the command LOAD, in which case the gun commander repeats the command. The piece is loaded, but is held fro m b attery until the battery cominander com- mands COMMENCE FIRING. 66 6-INCH GTTN SKILL. 87 When the number of rounds specified has been fired, the gun commander commands CEASE PntlNG, at which command all cannoneers resimie their posts. When the number of rounds is not specified, the battery com- mander commands CEASE FIRING, and the gun commander repeats the command. 165. When dummy ammunition is used, the piece is unloaded at the command CEASE FIRING, unless otherwise ordered. 166. The following driU is prescribed: 68 6-IWCH GTJW DRILL. 6-inch gun drill (disappearing carriage) Details. At command DETAILS, POSTS. At command EXAMINE GUN. Gun commander ( noncommissioned otfcer). The gun commander gives the command DETAILS, POSTS, and supervises the procuring of equipments and implements. He posts the reserve detachment. The gun commander gives the command EXAMINE GUN, makes a general in- spection of the gun and car- nage, and reports to the em- placement officer. Gun pointer (noncommissioned officer or private). The gun pointer procures the sight, places it in its seat, and takes post on the sighting platform. The gun pointer examines the sight and verifies the adjustment of the azimuth Index. He examines the traversing mechanism and the electric firing mechanism and circuit (if used). Range setter (noncommissioned officer or private). The range setter takes post facing the range scale. The ran^e setter examines the elevatmg and retracting mechanisms. He cleans and oils the gears. Range recorder (noncommissioned officer or private). The range recorder procures chalk, a ruler, a blackboard eraser, and a stop watch, and takes post at the time-range board. The range recorder exam- ines the time-range board. He puts on the head set and tests the telephone to the plotting room. Deflection re- corder (noncom- missioned officer or private). The deflection recorder pro- cures chalk and a blackboard eraser, and takes post at the deflection recorder's board. The deflection recorder ex- amines the deflection re- corder's board. He puts on the head set and tests the telephone to the plotting room. Breecli detail, No5. 1, 2, and 3. No. 3 is the chief of breech. No. 1 procures a mper or cotton waste and a can con- taining lubricating oil, and a sponge. He places the can convenient to the breech and takes post about 2 feet to the rear and right of the breech, facing it. No. 2 procures the loading tray (if one is used) and a ivlper or cotton waste. He places the tray convenient to the breech and takes post about 2 feet to the rear and left of the breech, facing it. No. 3 procures the lanyard (%yhen one is used), primers, primer pouch, punch, drill, reamer,andflringmechanism, and takes post about 2 feet to the right of the breech on line with its face, facing It. No. 1 removes the breech cover and places it at the designated place. He ex- amines, cleans, and oils the breechblock and breech mechanism. No. 2 examines, cleans, and oils the breech recess and gas-check seat. No. 3 examines the vent and the firing mechanism. He clears the vent and cleans the primer seat. He exam- ines the chamber and bore and gives the necessary or- ders for cleaning them. e-iNCH GUN saiii. 6-inch gun drill (disappearing carriage). 6d At command LOAB. At command CEASE FIR- ING (when dummy am- mtmition is used). The gmi commander gives the command L AD and supervises the work of his section. After No. 3 has given the command TEIP, the gun com- mander sees that the gun goes fully into batterv, verifies the range setting, and if the setting is cor- rect, calls KEADY. The gun commander gives the command CEASE FIR- ING and supervises the workolunloadmg. The gun pointer sets the deflection recorded on the deflection recorder's hoard and directs the traversing so that he will be on the target hy the time the gun is in battery. He fires the piece or gives the command ii'liiE as soon after the con^- mand H.EADT as the piece is pointed. No duties. At the command TRIP the range setter lays the piece for range in accordance with information obtained from the time-range board, as described in par. 400. No duties. The range recorder continues plotting the time- range curve. The range recorder con- tinues plotting the time- range curve. The deflection recorder makes a record of the last deflection received when it differs from the last one recorded, erasing the latter. The defiection recorder continues recording deflec- tions. No. 1 opens breech, cleans and oils the block when necessary, and as soon as the powder charge has been inserted he closes the breech. When the piece Is fired he seizes the lever handle as soon as the gun has recoiled within reach and opens the breech for the next charge. No. 2 unhooks the lanyard (if one is used) after the piece is fired. When the breech has been opened he wipes oft the mushroom head and the gas-check seat and puts the loading tray in place. He withdraws the loading tray after the projec- tile has been rammed to permit insertion of the powder tray, and_pushes the powder into the chamber by hand from the tray just far enough so that the breechblock will give the powder charge a final push in closing. No. 3 inserts a_primer after the breechblock is completely closed and lowers the leaf of the firing device completely down. He hooks the lanyard (if one Is used) before theprimer is inserted, com- manding IN BATTEKy in time to add TRIP after the primer is inserted. As the gun goes in battery he steps to the rear and right and pulls the lanyard (if one is used) at the command FIRE. As soon as the breech is opened after firing he removes the old primer, clears the vent, and cleans the primer seat. No. 1 opens breech. No. 2 withdraws the dummy powder charge. No. 3 removes the primer. 7d e-nrcH gun DRiii. 6-inch gun drill {disappearing carriage) — Continued. Details. At command DETAILS, POSTS. At command EXAMINE GUN. Rammer detail, No. 4. No. 4 procures the rammer and takes post about 4 feet in rear of the breech, facing it. He holds the rammer in his right hand, in a vertical posi- tion, its head on the platform by his right foot. No. 4 assists the breech de- tail in cleaning when neces- sary. Projectile detail, Nos. 6 and 6. No. 5 takes post near the serving table. No. B procures the extractor for dummy projectile, places it at the designated place, and takes jfost near the serv- ing table. No. 5 assists No. 7 in filling the recoil cylinders, un- screwing and, alter inspec- tion ,replacing the filling plug on the side of the carriage opposite to the post of No. 7. When called for by No. 7, No. 5 passes to him the fun- nel and the measure con- taining hydrolene oil, and receives them back from No. 7 when the cylinders have been filled. No. 6 removes the muzzle cover and places It at the designated place. He then assists the range setter in ex- amining the elevating and retracting mechanisms and in cleaning and oiling the gears. Tripping detail. No. 7. No. 7 procures the wrench for filling plugs, a measuje containing nydi'olene oil, and a funnel, and takes post at the tripping lever which is nearer the safety switch. No. 7 uncrews the filling plug on his side ot the gun, and if oil is needed calls on No. 5 for the funnel and measure and pours oil into his cylinder slowly. When both cylinders are full he hands the funnel and meas- ure back to No. 5 and noti- fies the gun commander that the cylmders are ready for inspection. After this in- spection, he screws both plugs well home and re- places his implements. Powder serving detail, Nos. 8 and 9. Nos. 8 and 9 procure two powder trays and take post, each with a tray , at that point of the loading platform most convenient to the source of powder supply. Nos. 8 and 9 remove the drip pans and inspect the powder trays. Sponge detail, No. 10. No. 10 procures the cham- ber sponge and a vessel con- taining liquid for sponging, places them near the railing, and takes post near the cham- ber sponge, facing the gun. (If there is to be no firing the vessel may be empty.) No. 10 brings up the cham- ber sponge when called for and sponges the chamber. 6-INCH GTTN SBTLL. 71 6^nch gun drill {disappearing carriage) — Continued. 1 Af. r^nTTlTTlnTKi T.nA"n At command CEASE FIR- INCr IJwhen dummy am- munition is used). As soon as a projectile is launched cm the load- ing tray No. 4 rushes the projectile forward hard into its seat, using all possible force and contin- ually increasing speed until the projectile is seated. No. 4 brings up the ex- tractor and withdraws the dummy projectile to where it can be seized by No. 5 or 6. Nos. 5 and 6 alternately pick up projectiles from the serving table and insert them in the bieech. The number not loading a projectile arranges the remaining projectiles on the serving table, and keeps the table coavenient to the breech. Nos. 5 and 6 alternately remove dummy projectiles No. 4 has left them, and place them on the serving table. No. 7 raises the tripping levers at the command TB.IP of No. 3, and if firing by electricity closes the safety switch as soon as the gun is in battery. No duties. Nos. 8 and 9 alternate in serving powder to the gun. The end of the powder tray is placed in the breech rfress after the loading tray has been re- moved, and No. 2 pushes the powder into the chamber by hand. Nos. 8 and 9 alternate in bringing up empty powder trays to receive the dummy powder charges. No. 10 dips the chamber sponge in the liquid tor sponging and allows the excess liquid to run off. As soon as the breechblock is opened after each shot he sponges the chamber as quickly as prac- ticable. No duties. (,C. C.A.D.R. Nos. 2 and e.) 72 e-INCH euH DUILI. NOTES ON THE DRILL. 167. To retract the gun. — ^To bring the gun from the firing to the loading position by hand the gun commander commands (1) FBOM BATTERY, (2) HEAVE, (3) HALT. At the first command No. 7 goes to the retraction crank, releases the retaining pawl and turns the speed crank to permit the pulling out of the cables. Nos. 5 and 6 mount on the carriage. Nos. 1 and 2 pull out the cables and pass the ends to Nos. 5 and 6, who place the loops of the cables on the hooks. No. 7 takes in the slack. Nos. 8 and 9 take positions at the retraction crank, and at the second command tm'n the crank. Nos. 5 and 6 relieve Nos. 8 and 9 when directed by the gun commander. When the gun has reached the loading posi- tion, the command HALT is given. At this command, No. 7 lets out enough slack to enable Nos. 1 and 2 to take the loops off the hooks. Chapter XI. 12-INCH GTJN DBIIL (BAKBETTE CABEIAGE). THE GTTK SECTION. 168. Each emplacement is maimed by a gun section (42 enlisted men plus the reserve detachment) conBisting of a gun detachment, an ammunition detachment, and a reserve detachment. The gun commander is in command of the gun section, and is also chief of the gun detachment. 169. The gun detachment (29 enlisted men) consists of the gun commander, the gun pointer, the chief of breech, the range setter, the range recorder, the deflection recorder, and 23 cannoneers, numbered from 1 to 23, inclusive. The gun detachment is divided into details, as shown in the drill which follows. 170. The ammunition detachment (13 enlisted men) consists of the chief of ammunition and 12 cannoneers, numbered from 24 to 35, inclusive. The ammunition detachment is divided into details for the service of powder and projectiles according to the location of magazines, shot rooms, and hoists pertaining to the emplacement . 171. The reserve detachment consists of all imassigned can- noneers. It is divided into two reserve details, one for the gun detachment and one for the ammunition detachment. The reserve detachment is posted by the gun commander at some convenient place or places, and is used by him to fill vacancies in the other detachments. 172. To post the gun section. — ^The section is posted as described in detail in paragraph 40. The gun commander commands DETAILS, POSTS, and after the cannoneers are posted, he com- mands EXAMINE GUN. 173. To call off. — The battery commander may at any time give the command CALL OFF, which is repeated by the gun com- mander. The cannoneers call off their numbers, beginning at 1. 174. To load and fire. — The battery commander indicates the target, as prescribed in Chapter V. He designates the kind of pro- jectile to be used, and after tracking has begun, commands: (a) COMMENCE FIRING. (6) FIBE BOUNDS, COMMENCE FIBING. (c) NUMBEB(S) FIBE SHOTS, COMMENCE FIBING. The gun commander commands LOAD w hen the battery com- mander gives the command COMMENCE FIBING, and before each shot of a series. The battery commander may give the command LOAD, in which case the gun commander repeats the command. The piece 74 12-INCH GUN DRILL is loaded, but not fired until the battery commander commands COMMENCE rmiNG. When the number of rounds specified has been fired the gun commander commands CEASE FIBING, at which command all cannoneers resume their posts. When the number of rounds is not specified, the battery com- mander commands CEASE FIRING, and the gun commander repeats the command. 175. When dummy ammunition is used, the piece is unloaded at the command CEASE FIRING, unless otherwise ordered. 176. The following drill is prescribed: 16 12-lNCH GUN DftlLl. 12Anch gun drill (barbette carriage). Details. At command DETAILS, POSTS. At command EXAMINE GTTN. Gun commander (noncommissioned officer). The gun commander gives the command DETAILS, POSTS, and supervises the procuring of equipment and implements. He posts the reserve detachment. The gun commander gives the command EXAMINE GUN", makes a general in- spection of gim and carriage, and reports to the emplace- ment officer. Gun pointer (noncommissioned officer or private). The gun pointer procures the sight, places it in its seat, and takes post on the sighting platform. The gun pointer examines the sight and verifies the ad- justment of the azimuth index. He examines the traversing mechanism and the electric firing mechan- ism and circuit (if used). Range setter (noncommissioned oiBcer or private). The range setter takes post on the range setter's platform. The range setter examines the elevating mechanism, and cleans and oils the gears, if necessary. Range recorder (noncommissioned officer or private). The range recorder procures chalk, a ruler, a blackboard eraser, and a stop watch, and takes post at the time-range board. The range recorder in- spects the time-range board. He puts on the head set and tests the telephone to the plotting room. Deflection re- corder (noncom- missioned officer or private). The deflection recorder pro- cures chalk and blackboard eraser and takes post at the deflection recorder's board. The deflection recorder iai- spects his board. He puts on the head set and tests the telephone to the plotting room. 12-IlICH GUN DKILL. 12-inch gun drill {barbette carriage). 77 At command 1.0 AS. At command CEASE FIK- ING (when dummy am- munition is used). The gun commander gives the command LOAD and supervises the work of his section. If the wece is ready for flring when the range setter calls The gun commander gives the command CEASE i'lK- DTG and supervises the work of unloadmg. The gun potater sets the deflection recorded and directs the traversing so as to follow the target. He fires the piece or gives the command FIRE as soon after the command KEADT as the piece is pointed. No duties. The range setter lays the piece for range in ac- cordance with information obtained from the time- range board as described in par. 400. He then calb 6, requiring the piece to be brought to an approx- imately horizontal position after each shot. (Note.— When available, the battery com- mander may detail an extra noncommjssioned offlcer to check the range.) The range setter directs the piece to be brought to an ap- proximately horizontal posi- The range recorder continues plotting the time- range curve as prescribed in par. 400. The range recorder con- tinues plotting the time- range curve. The deflection recorder makes a record of the last deflection received when it differs from the preceding one, erasing the latter. The deflection recorder continues recording deflec- tions. 78 12-INCH GTTN DRILL. 12-inch gun drill {barbette carriage) — Continued. At command DETAILS, POSTS. At command EXAMnSTE GUN. Breech detail, chief of breech ( noncommissioned officer or private) and Nos. 1,2, and 3. The chief of breech takes post 1 yard in rear of No. 2. No. 1 procm:es the trans- lating roller, a wiper or cot- ton waste, a can containing lubricating oil and a sponge; he places the can convenient to the breech, the translating roller in position, and takes post on the loading platform immediately to the rear and on the right of the breech, facing it. No. 2 procures a wiper or cotton waste and the loading tTa.y; he places the tray con- venient to the breecn and takes post to the left of No. 1, facing the breech. No. 3 procm-es the lan- yard (If one is used), primers, primer pouch, pimcn, drill, reamer, and firmg mechan- ism, and takes post on the platform to the nght of No. 1, lacing the breech. The chief of breech exam- ines the breech mechanism, breechblock, breech recess, chamber, and bore, and gives the necessary orders for cleaning and putting them in conaition for service . No. 1 removes the breech cover and passes it to No. 4. He cleans and oils the breechblock and mechan- ism. No. 2 cleans and oils the breech recess and gas check seat. No. 3 examines the vent and firing mechanism. He clears the vent and cleMis the primer seat. He frees the lanyard (if one is used) of kinks and hangs it on a hook outside the platform rail on the right side of the carriage. Rammer detail, Nos. 4, 20, and 21. No. 4 procures the rammer and places it on the prop. No. 21 procures the extractor for the dummy projectile and S laces it near the rammer. Tos. 4 and 21 take post in rear of the loading platform. No, 4 on the right and No. 21 on the left. No. 20 procures the cham- ber sponge and places it on the prop. He procures a ves- sel containing liquid for sponging and places it in rear of the loading platform to the right of the prop, and takes post in rear of Nos, 4 and 21. (When firing Cs not to take place the vessel may be empty.) Nos. 4 and 21 assist the breech detail in cleaning when necessary. No. 20 passes up the sponge called for, receives it back and assists in spong- ing when necessary. 12-INCH GTTN DRIII. 12-inch gun drill (barbette carriage) — Continued. 79 At command LOAD. At command CEASE FIR- ING. (When dummy am- m,miition is used.) The chief of breech sees that the projectile is pushed carefully off the tray until its base is just inside the powder chamber, and commands HOME RAM, when the projectile is rushed for- ward hard into it« seat, the ramming detail in- creasing the speed of the rush so that the projec- tile will have its fastest movement when it comes into its seat. He assists in ramming the projec- tile, withdraws the rammer, and assists in ram- mii^ the first three sections of powder; he hooks the lanyard (if one is used) before the primer is in- serted, nolds. the lanyard until No. 3 has stepped clear of the recoil, and thffli steps clear of the recoil , After the piece is fired he unhoots the lanyard (if one is used ), assists in spongiog^ and returns the sponge to No. %. No. 1 receives the rammer and places its head against the base of the projectile, assists in ram- ming the projectile and powder charge, inserts the first and third sections of powder, closes the breech, and steps clear of the recoU. After the piece is fired he receives the chamber sponge from No. 20, assists in sponging the chamber, wipes off the breechblock, and oils the threads. No. 2 inserts the loading tray, swings the pro- jectile iato position, assists in ramming the pro- jectile, inserts the second and fourth sections of the powder charge, seeing that the last section is left so that it will be pushed into place by the mushroom -head, removes the loading trap^, and steps clear of the recoil. After the piece is fired he wipes off the gas-check seat and breech recess. No. 3 opens breech. After the breech has been fully clceed, rotated, and lanyard (if one is used) hooked, he inserts the primer^ lowers the firing leaf, and steps clear of the recoil. After the piece has been firea he prepares the vent while the piece is being loaded. No. 4, assisted by No. 21, tosses up the rammer so it can be seized by No. 1, mounts on the loading platform, assists in ramming the projectile and J)owder charge, dismounts, takes the end of the anyard (if one is used) and pulls it at the com- mand FIRE. No. 20 passes the chamber sponge to No. 1 im- mediately after the piece has been fired; he re- ceives It back from the chief of breech and places it on the prop. (During firing he keeps the sponge head in liqind for sponging while the piece is oeing loaded.) He places the rammer, received from No. 21, on the prop. No. 21 mounts on the loading platform after he has passed up the rammer, assists in ramming the projectile and powder charge, passes the rammer back to No. 20, and dismounts. The chief of breech super- vises. No. 1 passes the first and third sections of dummy powder to Nos. 14 and 16, and assists in withdrawing the dummy projectile. No. 2 inserts the loading tray as soon as the breech is opened and passes the second and fourth sections of dum- my powder to Nos. 13 and 15, assists in withdrawing the dummy projectile and in swinging it clear of the plat- form. No. 3 opeos breech, re- moves the primer, and as- sists in withdrawing the dummy projectile. No. 4 mounts on the load- ing platform, receives the ex- tractor from No. 20, pulls back the dummy powder sections, assists in withdraw- ing the dummy projectile, and returns the extractor to No. 20. No. 20 passes the extractor to No. 4, receives it back from him, and places it on the prop. No. 21 mounts on the loading platform and assists in withdrawing the dummy projectile. 80 12-INCH GUN DRILI. 12Andi gun drill (barbette carriage) — Continued. Details. At command DETAILS, POSTS. At command EXAMINE GUN. Elevating detail; Nos. 5 and 6. No. 5 takes post at the ele- vating handwheel on the right side of the carriage, fac- ing it. No. 6 takes post at the ele- vating handwheel on the left side of the carriage, facing it. Nos. 5 and 6 assist the range setter in examining the elevating mechanism, and in cleamng and oiling the gears. Traversing detail; Nos. 7 and 8. Nos. 7 and 8 procure the traversing cranks, place them on the shaft and take post thereat. Nos. 7 and 8 remove the drip pans and assist in test- ing the traversing mechan- ism. Hoist tackle de- tail; Nos. 9, 10, 22, and 23. No. 9 is chief of detailunless a nonconunissioned officer is assigned in charge. No. 9 procm'es the wrench for filling plugs, a measure containing hydrolene oil, and a funnel, and takes post oppo- site the hoist tackle, one yard from and facing the piece. No. 10 procures a wrench for the filling plugs, and takes post in rear of the windlass crank handle, facing it. No. 22 takes post on the left of No. 10. No. 23 takes post in front of the windlass crank handle, facing it. Nos. 9 and 10 mount on the chassis, each carrying a wrench, and remove the fill- ing plugs from the recoil cyl- inders . If oil is needed. No. 9 calls on No. 23 for the funnel and measure and pours oil into the right cylinder, slow- ly; No. 10 watches the oil in the left cylinder. When botii cylinders are full No. 9 hands the fxmnel and meas- ure back to No. 23 and noti- fiesthe gun commander that the cylinders are ready for Inspection. After the ia- speotion Nos. 9 and 10 screw the filling plugs well home and replace their imple- ments. No. 22 examines the tackle on the hoisting gears and cleans and oils the parts. No. 23 removes the muzzle cover, places it at the desig- nated place and assists No. 9 in filling the recoil cylinders , passing up the funnel and oil measure when needed. Truck detail; Nos. 11 and 12. Nos. 11 and 12 bring out shot trucks to be used and take post at the handles of the first truck. No. 11 on the right and No. 12 on the left. Nos. 11 and 12 examine the trucks, and clean and oil them when necessary. They then turn them over to the hoist detail for load- ing. When the first truck is loaded, they push it to a po- sition immediately under the hoisting tackle on the carriage. Powder serving detail; Nos. 13, 14, 15, and 16. All take post at the station designated for the battery. No duties. 12-INCH GVH DRILL. 12-inch gun drill (barbette carriage) — Continued. 81 At command LOAD. At command CEASE FIR- ING. (When dummy am- munition is used.) Nos . 5 and 6 elevate and depress the piece under the direction of the range setter. Nos. 5 and 6 depress the piece as directed by the range setter. Nos. 7 and 8 traverse the piece under the direc- tion of the gun pointei . No duties. No. 9 hoolcs the hoist tackle to the shot tongs, commands HOIST, and steadies the projectile as it rises, mounts the steps^ commands HALT when the projectile is at the height of the breech. He as- sists in swinging the projectile around to the breech, unfixes the shot tongs, and swings them clear of the loading platform. He commands LOWER, passes the empty shot tongs to No. 20, and hooks the tackle to the shot tongs of another projectile. He directs the work of the hoist detail so as to have a projectile hoisted to the proper height by the time the piece is ftred. Nos. 10 and 22 assist in hoisting the projectile. No. 23 assists in hoisting the projectile, lowers the shot tongs, and attends to the pawl. No. 9 swings the shot tongs over the projectile, assists in swinging the projectile clear of the loading platform, and commands LOWER. Nos . 10, 22, and 23 lower the dummy projectile onto the truck. As soon as the first projectile is hoisted, Nos. 11 and 12 pull the empty truck aside and push the second truck under the hoist tackle. Then they return with the empty truck to the ammumtion hoist, turn it over to the ammunition hoist detail, and take post behind a loaded truck. As soon as the pieceis fired they run this truck rapidly to the position described vmder "DETAILS, POSTS" tor the second truck, pull the empty truck away from the hoisting tackle, and proceed as above. Nos. 11 and 12 push a truck into position under the hoist tackle. Nos. 13, 14, 15, and 16 move at a run, each with a section of the powder charge, passing them up to Nos. 1 and 2 on the loading platform, and return to their posts. Nos. 13, 14, 15, and 16 each receive a section of the dummy powder charge and return them to their posts. 104227° 82 12-INCH GUN DRILL. 12-inch gun drill {barbette carriage) — Continued. Details. At command DETAILS, POSTS. At command EXAMINE GTTN. Hoist detail; Nos. 17, 18, and 19. No. 17 is chief of detail unle-ss a noncom- missioned officer is assigned in cliarge. Nos. 17, 18, and 19 take post at the delivery table. Nos. 17, 18, and 19 exam- ine and clean the delivery table, and the projectiles on it. They examine the auto- matic stop. They load the trucks turned over to them by the truck detail. 12-INCH GUN DRILL. 12-inch gun drill (barbette carriage) — Continued. 83 At command LOAD. At command CEASE FIH.- HfG. (When dummy am- munltlon is nsed.) Nos. 17, 18, and 19 receive the empty truck after each shot, load it, and run it out conveniently for Nos. 11 and 12. Mo duties. (C. C.A.D.S.m.S^ 84 12-INCH GUN DRILL. NOTES ON THE DRILL. (See also Chapters V, XV, and XVI.) 177. To open and close breech. — The breech must not be opened until the piece has been depressed to an approximately horizontal position- when open, the piece must not be elevated until the breechblock is swung to the left in the oper'ation of closing breech. 178. To open breech (1888 mechanism). — No. 3 releases the ro- tating crank by turning the rotating crank catch to the left and turning the rotating crank clockwise as indicated by the "open" arrow until it brings up short in a horizontal position and is secured by its catch; he then briskly turns the translating crank contra- clockwise. When the shoulders of the grooves strike against the ends of the rails, the block stops short and the shock frees the tray latch from its catch, and the tray and block are swung to the right until the securing latch engages in the catch. 179. To close the breech (1888 mechanism)'. — No. 1 releases the securing latch from the catch, assisted by No. 3 swings the tray and block around smartly to the left, seizes the handle of the tray, and_ continues the swinging of the block until the tray abuts against and is latched to the face of the breech; he then turns the translating crank clockwise until the block is translated completely; releases the rotating crank by turning the rotating crank catch to the left, and turns the rotating crank contraclock- wise, as indicated by the "close" arrow, until it brings up short in a vertical position and is secured by its catch. Chapter XII. 8 OB 10 INCH GTIN DBILL (BABBETTE CASBIA6E). 180. The drill for the 8-inch or 10-inch gun (barbette carriage) is the same as that for the 12-inch gun (barbette carriage) ■with the following exceptions: The gun detachment consists of 20 cannoneers instead of 23: Nos. 21, 22, and 23 being omitted. No. 4, instead of No. 21, passes the rammer to No. 20. No. 10, instead of No. 22, examines the tackle on the hoisting gears. No. 8, instead of No. 23, removes the muzzle cover and passes the funnel and measure to and re- ceives them from No. 9 when the recoil cylinders are filled. The ammunition detachment consists cf 10 cannoneers (instead of 12), whose numbers run from 21 to 80, inclusive. 85 Chapter XIII. S OR 6 INCH GTJN DRILL (BARBETTE CARRIAGE). THE GUN SECTIOir. 181. Each emplacement is manned hy a gun section (21 enlisted men plus the reserve detachment) consisting of a gun detachment, an ammunition detachment, and a reserve detachment. The gun commander is in command of the gun section, and is also chief of the gun detachment. 182. The gun detachment (14 enlisted men) consists of the gun commander, the gun pointer, the range setter, the range recorder, the deflection recorder, and 9 cannoneers, numbered from 1 to 9, inclusive. The gun detachment is divided into details as shown in the drill which follows. 183. The ammimition detachment (7 enlisted men) consists of the chief of ammunition and 6 cannoneers, numbered from 10 to 15, inclusive. The anununition detachment is divided into de- tails for the service of powder and projectiles according to the location of magazines, shot rooms, and hoists pertaining to the emplacement. 184. The reserve detachment consists of all unassigned cannon- eers. It is divided into two reserve details, one for the gun de- tachment and one for the ammunition detachment. The reserve detachment is posted by the gun commander at some convenient place or places, and is used by him to fill vacancies in the other detachments. 186. To post the gun section. — The section is posted as prescribed in detail in paragraph 40. The gun commanaer commands DE- TAILS, POSTS, and after the cannoneers are posted, he commands EXAMINE GUN. 186. To call off. — The battery commander may at any time give the command CALL OFF, wluch is repeated by the gun com- mander. The cannoneers call off their numbers beginning at 1. 187. To load and fire. — The battery conmiander indicates the target as prescribed in Chapter V. He designates the kind of projectile to be used, and after tracking has begun, commands: (a) COMJtENCE FIRING. (6) FIRE ROUNDS, COMMENCE FIRENG. (c) NUMBER(S) — FIRE SHOTS, COMMENCE FIRING. The gun commander commands LOAD when the battery com- mander gives the command COMMENCE FIRING, and before each shot of a series. The battery commander may give the command LOAD, in which case the gun commander repeats the command. The piece is 86 5 OK 6 INCH GTTN SBILI. 87 loaded, but is not fired until the battery commander commands COMMENCE TTBTNG. When the number of rounds specified has been fired the gun commander commands CEASE FEBING, at which command all cannoneers resume their posts. When the number of rounds is not specified, the battery com- mander commands CEASE FT&VSG, and the gun commander repeats the command. 188. When dummy ammunition is used, the piece is unloaded at the command CEASE FIRING, unless otherwise ordered. 189. The following drill is prescribed: 88 5 OB 6 INCH GUN DRILL. 5 or 6 inch gun drill {barbette carriage). Details. At command DETAILS, POSTS. At command EXAMINE GUN. Gun commander (noncommissioned officer). The gun commander gives the command DETAILS, POSTS and supervises the procuring of equipments and implements. He posts the reserve detachment. The gun commander gives the command EXAMINE GUN, makes a general in- spection of the gun and car- riage, and reports to the em- placement oiBcer. Gun pointer(non- coramissioned offi- cer or private). The gun pointer procures the sight, places it in its seat, and takes post on the sight- ing platform'. The gun pointer examines the sight. He examines the traversmg mechanism and the electric firing mechan- ism and circuit (if used). Range setter (noncommissioned officer or private). The range setter takes post facing the range scale. The range setter tests the elevating mechanism. He cleans and oils the gears. Range recorder (noncommissioned officer or private). The range recorder pro- cures chalk, a ruler, a black- board eraser, and a stop watch, and takes post at the time-range board. The range recorder exam- ines the time-range board. He puts on the head set and tests the telephone to the plotting room. Deflection re- corder (noncom- sioned officer or private). The deflection recorder procures chalk, and a black- board eraser, and takes post at the deflection recorder's board. The deflection recorder examines the deflection re- corder's board. He puts on the head set and tests the telephone to the plotting room. Breech detail, Nos. 1, 2, and 3. No. 3 is the chief of breech. No. 1 procures a wiper or cotton waste and a can con- taining lubricating oil and a sponge. He places the can convenient to the breech and takes post about 2 feet to the rear and right of the breech, facing it. No. 2 procures a loading tray (if one is used) and a wiper or cotton waste. He places the tray convenient to the breech and takes post about 2 feet to the rear and left of the breech, facing it. No. 3 procures the lanyard (if one is used), primers, primer pouch, punch, drill, reamer, and firing mechanism and takes post about 2 feet to the right of the breech on line with its face, facing it. No. 1 removes the breech cover and places it at the designated place. He exam- ines, cleans, and oils the breechblock and breech mechanism. No. 2 examines, cleans, and oils the breech recess and gas check seat. No. 3 examines the vent and the firing mechanism. He clears the vent and cleans the primer seat. He examines the chamber and bore and gives the necessary orders tor cleaning them. Rammer detail. No. 4. No. 4 procures the rammer and takes post about 4 feet in rear of the breech, facing it. He holds the rammer m a vertical position with his right hand, its head on the platform by his right foot. No. 4 assists the breech detail in cleaning when necessary. 5 OE 6 INCH GUN DRILL S or 6 indi gun drill (barbette carriage). 89 At command LOAD. At command CEASE FI£- ING (when dummy am- munition is used). The gun commander gives the command LOAD and supervises the work of his section. He veri- fies the range setting, and if the setting is correct The gun commander gives the command CEASE FIS- DTG and supervises the work of unloading. The gun pointer sets the deflection received and follows the target continuously. He fires the piece (or gives the command F1B.E) as soon after the command RTIAHY as the piece is pointed. No duties. The range setter lays the piece for range in ac- cordance with data obtained from the time-range board, as prescribed in paragraph 400. No duties. The range recorder continues plotting the time- range curve, as prescribed in paragraph 400. The range recorder contin- ues plotting the time-range curve. The deflection recorder makes a record of the last deflection received when it differs from the last one recorded, erasing the latter. The deflection recorder continues recording deflec- tions. No. 1 opens breech, cleans and oils the block, when necessary, and as soon as the powder charge has been inserted he closes breech. He seizes the lever handle as soon as possible after the piece is fired and opens breech for the next shot. No. 2 unhooks the lanyard (if one is used) after the piece is flred. When the breech has been opened he wipes off the mushroom head and gas- check seat and puts the loading tray in place. He withdraws tne loading tray after the projec- tile has been rammed to permit insertion of the powder tray, and pushes the powder into the chamber by hand from the tray. No. 3 inserts a primer after the breechblock is completely closed and lowers the leaf of the firing device completely down. He hooks the lanyard (if one is used) before the primer is inserted and pulls the lanyard at the command FIB£. As soon as the breech is opened after firing, he re^ moves the old primer, clears the vent, and cleans the primer seat. No. 1 opens breech. No. 2 withdraws the dummy powder charge. No. 3 removes the primer. At the command HOME RAM by the chief of breech. No. 4 rushes the projectile forward hard into its seat, increasing the speed of the rush so tlmt the projectile will have its fastest movement when it comes up hard in its seat. No. 4 brings up the ex- tractor and withdraws the dummy projectile. 90 5 Oa 6 INCH GUN DRILL. 5 or 6 inch gun drill {barbette carriage) — Continued. Details. At command DETAILS, POSTS. At command EXAMINE GUN. Projectile detail, Nos, 5 and 6. No. ,5 procures the wrench for filling plugs, a funnel, and a measure containing hydro- iene oil, and takes these to the recoil cylinder. After com- pleting his duties for EXAM- INE GUN, he replaces his implements and tal^es post near the serving table, facing the piece. No . 6 procures the extractor, for dummy projectiles, places it at the designated place, and takes post near the serving table. No. 5 unscrews the fiUing plugs and if oil is needed pours it in until it stands in the filling hole, waits a moment to allow the escape of air, and pours in more, if necessary. Thenhenotines the gun command er that the cylinders are ready for in- .spection. After the inspec- tion No. 5 screws the plugs well home, replaces his im- plements, and takes post near the serving table, fac- ing the piece. No. 6 removes the muzzle cover and places it at the designated place. He as- sists the range setter in ex- amining the elevating mech- anism and in cleaning and oiliQg the gears. Powder serving detail, Nos. 7 and 8. Nos. 7 and 8 procure two powder trays and take post, each with a tray, at that part of the loading platform most convenient to the source of powder. Nos. 7 and 8 examine the powder trays. Sponge detail, No. 9. No. 9 procures the chamber sponge and a vessel contain- ing liquid for sponging, places them near the railing, and takes post near the chamber sponge, facing the gun. (If there is to be no firing, the vessel may be empty.) No. 9 brings up the cham- ber sponge when called for and sponges the chamber. 5 OR 6 INCH GTTN DRILL. 5 or 6 inch gun drill {barbette carriage) — Continued. 91 At command LOAD. At command CEASE FIR- ING. (When dummy am- munition is used.) Nos. 5 and 6 alternately piot up projectiles Irom the serving table and insert them in the breech. The number not loading a prqjectile arranges the remaining projectiles on the serving table, and keeps the table convenient to the breech. Nos. 5 and 6 alternately re- move dummy projectiles from the breech recess where No. 4 has left them and place them on the serving table. Nos. 7 and 8 alternate in bringing up powder charges. The end of the powder tray is placed in the breech recess after the loading tray nas been removed, and No. 2 pushes the powder into the chamber by hand. Nos. 7 and 8 alternate in bringing up empty powder trays to receive the powder charges. No. 9 dips the chamber sponge in the liquid for sponging and allows the excess liquid to run off. As soon as the breechblock is opened after each shot, he sponges the chamber as quickly as practicable. No duties. ( a C.A.D. R. Nos. 2 and «.) Chapter XIV. 3-INCH, 4-INCH, OK 4.7-INCH GUN DRILL. THE GUN SECTION. 190. Each emplacement is manned by a gun section (12 enlisted men plus the reserve detachment) consisting of a gim detachment, an ammunition detachment, and a reserve detachment. The gim commander is in coramand of the gun section, and is also chief of the gun detachment. 191. The gun detachment (6 enlisted men) consists of the gun commander, the gun pointer, the range setter, and three cannoneers numbered from 1 to 3, inclusive. The gun detachment is divided into details as shown in the drill which follows. 192. The ammunition detachment (6 enlisted men) consists of the chief of ammunition and 5 cannoneers, numbered from 4 to 8 inclusive. The ammunition detachment is divided into details according to the location of niagazines and shot roonas pertaining to the emplacement. 193. The reserve detachment consists of all unassigned can- noneers. It is posted by the gun commander at some convenient place or places, and is used by him to fill vacancies in the other detachments. 194. To post the gun section. — The section is posted as prescribed in detail in paragraph 40. The gun commander commands DETAILS, POSTS, and after the cannoneers are posted, he commands EXAMINE GUN. 195. To call off. — The battery commander may at any time give the command CALL OFF, which is repeated by the gun com- mander. The cannoneers call off their numbers, beginning at one. 196. Method of firing. — Chapter VI describes the method of firing and of fire direction. 197. The following drill is prescribed: 94 3-INCH, 4-INCH, OR 4.7-INCH GUN DRILL. 3-inch, 4-inch, or 4-'y-inch gun drill. Details. At command DETAILS, POSTS. At command EXAMINE GUN. Gun commander (noncommissione d officer). The gun commander gives the command DETAILS, POSTS, and supervisee the procuring of equipment and implements. The gun commander gives the command EXAMINE GXTN, makes a general in- spection of the gun and car- nage, and reports to the em- placement officer. Gun pointer (noncommissioned officer or private). The gun pointer procures the sight and places it in its seat and takes post in rear of the shoulder piece, facing to the front. The gun pointer examines the sight and examines the traversing mechanism, the Ihing circuit (if one is in- stalled) and the lanyard (if used). Range setter (noncommissioned officer or private). The range setter takes post near the range scale if the car- riage is provided with one; otherwise at the elevating clamp, facing it. The range setter tests the elevating mechanism and cleans and oils the gears. Breech detail, Nos. 1 and 2; No. i ischief of breech. No. 1 procures a wiper or cotton waste and a can con- taining lubricating oil and a sponge. He places the can convenient to the breech and takes post about 2 feet to the rear and right of the breech, facing it. No. 2 procures a wiper or cotton waste and the sponge; he takes post about 2 feet to the rear and left of the breech, facing it. No. 1 removes the breech cover and places it at the des- ignated place. He examines the chamber, the bore, the breechblock and the breech mechanism, and cleans and oils them if necessary, as- sisted by Nos. 2 and 3. No. 2 removes the muzzle cover and places it at the des- ignated place, prepares the lanyard (if used), examines, cleans, and oils the breech recess, assisted by No. 3. Extractor detail, No. 3. No. 3 procures the hand ex- tractor and a pair of gloves. He takes post about 3 feet to rear of the breech, facing it. No. 3 removes the filling plug. If the cylinder is not full ne procures the measure containing hydrolene oil and the fimnel, pours Inoil until it stands in the filling hole, replaces the filling plug and the oil measure and funnel. 3-rNCH, 4-INCH, OR 4.7-INCH GUN DRILL 95 3-inch, 4-inch, or 4.7-inch gun drill. At command LOAD or COMMENCE FIRING. At command CEASE FIRING. The gun commander gives the command LOAD or COMMENCE FIKING and supervises the work of his section. The gun cotmnander gives the command CEASE FIR- ING and supervises the work of unloading. The gun pointer, having talcen the travel of the target and set his sight for deflection, follows the target continuously, commands CLAMP (if clamps are provided) and lircs or commands J: IKE as soon after the command READY as the piece is pointed. If Case I is used he sets the sight for both range and deflection. No duties. The range setter keeps the piece laid continu- ously tor range in accordance with the trans- mitted information, clamps the gun in elevation at the gim pointer's command and undamps im- mediately after the gun is fired. No duties. No. 1 opens breech, feels for the firing pin, closes the breech as soon as the cartridge is inserted, opening or closing the breech he wipes any resi- due from the threads of the breechblock and oils the mechanism. No. 2 picks up a cartridge and inserts it in the chamber, taking care that the point of the projec- tile does not strike. If there is difficulty in open- ing or closing breech he wipes any residue from the threads of the breech recess and oils the threads if they become dry. No. 1 opens the breech and closes it after the cartridge has been removed. No. 2. No duties. No. 3 receives the empty cartridge case as it is ejected and lays it aside. He uses the hand extrac- tor when necessary. No. 3 withdraws the car- tridge. (C. C.A.D.R. No.l.) 96 3-INCH, 4-INCH, OR 4.7-INCH GUN DRILL. NOTES ON THE DRILL. 198. All cartridges will be tried in the chamber before using. Those which do not fit accurately -will be rejected. 199. If a cartridge jams, attempt will not be made to drive it home by forcing the block; it will be withdrawn and another sub- stituted. 200. If a cartridge case is extracted with difficulty, the cause may be due to a burr around the edge of the chamber, and if one is found, it should be filed smooth. 201. With guns on masking parapet mounts. No. 3 procures the ratchet lever at the command POSTS, places it on the shaft, and at the command BAISE GTTN mans the ratchet lever, assisted by the range setter, who clamjjs the pivot socket. The same numbers lower the gun when the drill is dismissed. 202. For 4.7-inch guns, battery commanders are authorized to modify the above drill to meet requirements. Chapter XV. GENERAL INSTRUCTIONS FOR SERVICE AT THE EMPLACEMENTS. GENERAL INSTRUCTIONS. 203. The service of the piece will proceed with alertness and precision, and with as few orders as possible; aside from the neces- sary orders and instructions, no talking of any kind will be per- mitted. All movements of the cannoneers connected with the service of the piece will be made at a run. 204. The battery commander will train the gun commanders and guns pointers in giving commands, which will be quick and clear, but not louder than necessary. 205. Actual loading with dummy ammunition and pointing the gun as for service will be practiced at drills. 206. At the command TAKE COVER, given at any time, all cannoneers not designated to remain at their posts will move at a run to some designated place under cover. As a rule this com- mand will be given in mortar batteries only. 207. A drill pi-imer or a fired service primer will be used at drill. 208.^ The primer will be inserted after the breechblock is locked. The cannoneer who inserts the primer will be instructed to exer- cise the greatest care in lowering the leaf of the firing device. Under no circimistances will he insert or remove the primer by means of the button or wire. 209. Service friction primers are adjusted in manufacture to require a pull of about 25 pounds to start the wire to the rear, and about 40 to 45 pounds to pull the teeth through the compressed friction pellet and explode it. 210. The lanyard will be pulled from a position as near the rear of the gim as possible. A strong, quick pull (not a jerk) with as short a lanyard as practicable will be used. 211. Obturating primers are constructed so that when a primer is pulled and fails to fire, the primer wire is free to move forward without causing the composition to ignite. Extra precautions will be taken to prevent any attempt to use a primer that has failed. 212. Constant inspection of the safety pin on the firing leaf of the breech mechanisms in which combination primers are used will be made, since if the safety pin should be broken by harsh treatment and the pull upon the lanyard be upward by about 10° the primer probably would be ejected atthe instant of firing and might injure the man firing the piece. 213. SIGNALS. — ^The commands or signals ELEVATE, DE- PRESS, RIGHT, or LEFT, given in pointing, always refer to the direction of motion of the muzzle. ELEVATE. — Raise either hand to the height of the head, fingers pointing upward. ■ ■ ''•'■ ' '• ' i04227°— 17 7 97 " 98 SERVICE AT THE EMFLACEIAENTS. DEPRESS. — Kaise either hand to the height of the head, fingers pointing downward. RIGHT or LEFT. — ^Motion with either hand, fingers pointing in the desired direction. CLAMP. — Raise either hand with fist closed opposite neck, back of hand up, elbow bent and at height of shoulder. HALT. — Raise and fully extend either arm vertically, hand and fingers open in prolongation of arm. STAND FAST. — Raise and fully extend either arm horizontally straight to the front, hand and fingers open in prolongation of arm, back of hand up. TAKE COVER. — Raise and extend fully both arms horizonally in prolongation of line of shoulders, hands open, fingers extended and joined, backs of hands up. READY. — Raise either hand horizontally in front of forehead, fingers extended and joined, back of hand against forehead. 214. Signals with whistles or bugles are authorized. CARE IN SEATING THE PROJECTILE AT GVS BATTERIES OF THE MAJOR ARUAMENT. 215. The shot truck carrying the projectile will be brought up to the face of the breech and the projectile pushed carefully oft the truck until the base of the projectile is just inside the powder chamber. The truck will then be withdrawn and run off^to one side. The entire ramming detail will then man the rammer as near its outer end as possible. At the command HOME RAM by the chief of breech, the ramming detail will rush the projectile forward hard into its seat, increasing the speed of the rush so that the projectile will have its fastest movement when it comes up hard in its seat. 216. Powder serving tray. — For guns of the major and the inter- mediate armament, there will be made wooden serving trays, each having sufficient dimensions to carry all the sections of one powder charge. The tray will be so shaped that the forward end will cover the screw threads in the breech, and it will be provided with cross handles to facilitate handling. Powder sections will be ar- ranged in the same order they will have in the powder chamber. 217. As soon as the rammer has been withdrawn after seating the projectile, the nose of the powder serving tray will be inserted in the breech by the powder servers, and the rammer detail, in one motion, will push carefully the entire powder charge offi the serving tray to such a distance that the breechblock will give the powder charge a final push into the chamber in closing. The tray will then be removed and the breech closed. At least two trays will be provided for each gun. BORE SIGHTIN6. 218. Guns will be bore sighted frequently in order to check the adjustment of the sight standard and to correct it if necessary. The process is as follows: Place a bore sight in the breech and a thread in the vertical diameter of the muzzle. Sight through SERVICE AT THE EMPLACEMENTS. 99 the bore sight and bring the muzzle thread on a well-defined point of an object at or beyond the mean range for the piece. If a bore sight is not available, the vent or a thread in the vertical diameter of the breech niay be used. Good results have been obtained by placing one of the objectives of a field glass against the vent when the breech is closed, a thread being in the vertical diameter of the muzzle. The effect is to cause the thread to appear like the ver- tical hair in a telescope, and the accuracy in sightingis practically the same as if a telescope were centered in the gun. with the sight in adjustment on the sight bracket and the vertical wire set at nor- mal, the sight standard is adjusted until the vertical wire of the sight is brought on the point. 219. The azimuth indices of the guns of a battery will be set so that when the guns are aimed at a point near the main channel about midrange from the battery, the azimuth reading is the same for each; this will be the correct azimuth from the directing point or gun. In the event of there being two channels of equal impor- tance a point at midrange and midway between the channels will be taken. By this means the azimuth differences due to gun dis- placement may be disregarded and in Case III the guns laid at the azimuth of the target from the directing point or gun. 280. In gun batteries of the major armament, range differences will be stenciled on the base ring or on the step of the loading plat- form, so that the proper correction for the gun displacement will be the number nearest an index marked on the carriage near the elevation scale. ORIEITTATIOIfr OF MOKTARS. •281. The orientation of mortars will be tested frequently and the setting of the azimuth indices corrected, if necessary. Two con- venient methods are as follows: First. Having established two intervisible monuments in rear of the pits, and having determined accurately the azimuth of the line joining them, proceed as follows: Set up a transit over a monument from which the pit may be seen; take a reading on the other monument and record it; take a reading on a point in the pit and record it. Move the transit to this point in the pit and back sight on the monument; record the reading. Stretch strings across the vertical diameters of the breech and muzzle; point the mortar and the transit so that the axis of the mortar and line of collimation of the transit coincide; record the reading of the transit. From the readings taken, the azimuth of the mortar may be com- puted and the index set. The string across the bieech may be omitted; in which case the axis of the mortar is fixed by the muzzle string and vent, the mor- tar being pointed at the transit when this is being done. It must be remembered in calculating the azimuth that the mortar is point- ing in the opposite direction from the transit. ^Second. By using the instrument in the battery commander's station in connection with the transit when they are intervisible, loo SERVICE AT THE EMPLACEMENTS. the transit being at any point on the parapet from which it can be sighted into the pit. Adjust the transit. Set it up so that it can be sighted on the mortar and the battery commander's instrument; sight on the latter and record the reading. Sight the battery commander's instrument on the transit and record the reading. Point the mortar and transit so that the axis of the mortar coincides with the line of coUimation of the transit and record the transit reading. From the readings, the mortar azimuth maybe computed and tie index set. The correct setting of the index will be indicated by a tool mark on the racer. 222. The adjustment of quadrants attached to mortars will be tested frequently, and corrected by using a clinometer or a standard quadrant known to be in adjustment. METHODS OF POINTING. 223. Case I. — This method of pointing is used only with rapid- fire guns where means for laying in elevation by quadrant have not been provided. Direction and elevation are given by the sight. The gun pointer adjusts the sight in its seat and sets the elevation and deflection scales for the indicated range and deflection, respec- tively. Case II. — This is the normal method of pointing all guns. Direc- tion is given by the sight and elevation by an elevation or range scale attached to the carriage. For guns of the major armament the corrected range is taken from the time-range board. The gun pointer sets his sight to the deflection shown on the deflection recorder's board. Case III. — This method of pointing is used exclusively for mor- tars. Its use for guns is auxiliary and is limited to batteries where the prevalence of fog or other local conditions render it necessary. Direction is given by the azimuth circle and elevation by the ele- vation scale or by quadrant. In Case III guns are fired on the bell. Corrected azimuths for the first or second bell after the data are received are sent to the guns every 30 seconds. The gun pointer sets the azimuth for the bell on which it is desired to fire. The corrected range of the set- forward point for the same instant of firing is taken from the time- range board. POINTING TESTS. 224. — Pointing tests will be held frequently at gun batteries of the major armament in the following manner: An assumed deflection for wind and drift is used during the test. This deflection is changed frequently during the drill so that gun pointers may not know the reading that should be obtained at the end of the time of flight. To accomplish this, the platen of the deflection board is set for the assumed deflection, and the setting is not changed as long as the same assumed deflection is used. The gun pointer sets his sight at the deflection received from the plotting room, which is that obtained from the deflection board by SERVICE AT THE EMPLACEMENTS. 101 combining the correction for angular travel during the time of flight with the assumed deflection for wind and drift. He gives the command EIRE as soon after the conunand BEADY as he is on the target; traversing is stopped and he then follows the tai^et with the vertical wire. A noncommissioned officer equipped with a stop watch and a time-of-flight table starts the watch at the com- mand FIRE ; commands HALT and stops the watch af the expira- tion of the time of flight. The gun pointer stops following with the vertical wire at the command HALT, when the reading of the deflection scale should be the same as the assumed deflection for wind and drift. If not, the difference ia the error ip predicting and pointing. Example: Assumed deflection, 3.65; deflection sent to gun pointer, 3.20; reading of the deflection scale at end of time of flight, 3.60. 3.65-3.60=0.05, the error. For each trial records will be kept of the range to the target and the deflection error; and the gun pointer will be informed con- cerning the amount of his error. 225. The excellence of a gun pointer's work is determined, first, by the accuracy of his pointing; second, by the promptness with which he is able to give the command EIRE after the piece is 226. With disappearing guns it is important that the gun pointer be trained to get on the target in the time necessary to close the breech plus the tripping interval, so that in practice or action no time will be lost in pointing the gun after it is in battery. PREDICTIOK TESTS FOE UOETAR BATTERIES. 227. Prediction tests will be made frequently at mortar batteries in the following manner: The battery commander is assisted by an officer or noncommis- gioned officer equipped with a stop watch and a time-of-flight table. The azimuth of a predicted pomt and the corresponding tune of flight is sent to the battery commander, who sets his instrument to the azimuth of the predicted point, the vertical wire at normal. As the target passes the vertical wire of his instrument, he com- mands EIRE, and follows the target by turning t he d isk crank. The assistant starts the stop watch at the co m mand EIRE and calls "halt" at the expiration of the time_ of flight. The battery com- mander ceases tracking and the assistant records the reading of the instrument. The difference between this reading and the azimuth of the set-forward point as determined from the plotting board is the error in prediction. point, the az , Records of these tests will be kept and the results will be pub- lished to the battery command. Chapter XVI. TARGET PBACTICE— SALUTES. 828. Subcaliber and service target practice will be held in ac- cordance with special regulations published annually by the War Department.' SUBCALIBER PRACTICE. 229. In subcaliber practice, in order to simulate the conditions of service practice, the gun pomter of a gun on a disappearing car- liaee will not be permitted to follow the target continuously. He will be required to cease traversing from the time the breechblockis opened until the charge is inserted, this being the time when, in actual loading, the truck is at the breech. After the charge has been inserted he will endeavor to get on the target in the time necessary to close the breech, plus the tripping interval. Sub- caliber practice wUl simulate service practice as closely as possible. SERVICE PRACTICE. 230. Before service practice, the battery commander will satisfy himself that all the material to be used at the practice is ready for service, special attention being paid to the following: Adjustment of observing instruments. Condition of communications. Adjustment of plotting board and other equipment in the plot- ting room. Adjustment of sights and sight standards at gun batteries. Adjustment of azimuth indices at mortar batterie.s. Adjustment of range scales of guns and quadrants of mortars, using clinometer. Condition of recoil systems and setting of the throttling valves. Condition of elevating and traversing mechanisms. Adjustment of obturating devices. Condition of shot trucks. Weight and condition of projectiles. Weight and condition of powder sections. 231. Prior to service practice, the bore, including the powder chamber of each piece to be used in practice, will be cleaned thor- oughly and freed from grease and oil, the breechblocks will be (lifcmantled and carefully examined. 232. All powder to be used for target practice at any battery will be stored in the service magazines of the battery at which it is to be used for at least two weeks before the trial shots are fired. After being stored in a magazine for two weeks, the temperature of the magazine may be taken as the temperature of the powder 102 TARGET PRACTICE— SAITTTES. l03 without material error. The temperature of a magaziBe wUl be taken immediately upon opening the doors just prior to target jiractice. 233. Powder marked for one caliber or piece will not be used for any other caliber or piece of different chamber capacity. 234. In any case in which poor practice ia believed to have been caused by defective powder, a special detailed report will be made to The Adjutant General through military channels. 236. Projectiles will be cleaned carefully before being inserted in the bore, lubricant will be removed, and the bourrelets will be freed of paint. _ 236. Immediately after a piece is fired, the breech will be opened and the primer will be removed. 237. Care will be taken to prevent injury to the gas check seat and to keep it clean. If any residue from the priming charge drops from the obturator into the gas check seat or the breech recess it will be wiped off. 238. When service ammunition ia fired from guns (or mortars) above 4.7 inches in caliber, or when blank ammunition is fired from guns (or mortars) of any caliber, the powder chambers will be sponged and the mushroom head wiped oft after each round and before loading for the next round, in order to insure the extinguish- ment of aU sparks and the removal of smoldering fragments. The sponge and cloth used for this purpose will be dipped in the liquid for sponging and the surplus liquid will be removed from them before they are used. (C. C. A. D. R. No. 3.) 239. Immediately after firing, the piece and accessories will be inspected by the battery commander and a report on their condition will be made by him (through the fire and fort commanders) to the coast defense commander. The bores of pieces will be washed clean with water, dried, and oiled. The breechblocks will be dis- mantled, and aU parts cleaned and oiled. 240. When firing, officers and men will be advised to place the authorized ear protectors, cotton, or small pieces of waste in their ears, but they will not be permitted to place the finger tips in their ears. 241. Service practice will be preceded by careful instruction and will not be held by a company of coast artillery until such company is thoroughly familiar with the use of all of the equipment suppUed for the service of the battery at which the company is to fire. No man will be detailed to a position at the practice imless he has been well instructed in the duties pertaining thereto. 243. In case of a misfire in artillery practice the primer will not be removed and a new one inserted for at least 10 minutes; during the interval, the piece will be laid on some portion of the field of fire where its discharge will not endanger shipping. 243. If firing by electricity, the circuit will be broken before the primer is removed. When using fixed ammunition and per- cussion primers, a second trial of the primer will be made if the firing device can be cocked by hand without opening the breech, but if this also fails, the breech will not be opened and a new car- tridge substituted within 10 minutes. If it is found necessary to open the breech when using obturating primers, the vent will be 104 TARGET PRACTICE— SALUTES. examined and cleared if necessary and the rear section of the powder charge will be pulled a little to the rear, so that the mush- room head will push it to its place; the breech will be closed a,nd another primer will be tried. 244. At the command CEASE FIRING, lanyards will be de- tached. If using electric primers, the circuit will be broken. With rapid-fire guna using metallic cartridge cases, the breech will be opened. If firing is not to be resumed, fixed ammunition and separate powder charges will be withdrawn. Projectiles not loaded and fused will be driven back and withdrawn . Separate projectiles loaded and fused will be left in the gun until a favorable time to fire them; on no account will an attempt be made to drive them back. 245. Whenever a junior commander is ordered to fire under cir- cumstances which from his position he judges to be unsafe, he will hold the fire until he can report the condition to the next higher commander. SALUTES. 246. Salutes with cannon will be fired under the charge of a com- missioned officer. The interval between shots will be five seconds. Only guns using metallic cartridge cases will be employed in firing salutes. 247. In firing salutes, the powder chamber of the gun will be sponged and the mushroom head wiped off after each round to extinguish all sparks and to remove residue. The sponge and cloth used for this purpose will be dipped in the liquid for sponging and the surplus liquid will be removed before using. Worn sponges or those that do not fill the chamber of the gun will not be used. (C. C. A. D. R. No. S.) 248. Salutes will not be fired unless the above conditions can be fulfilled. Chapter XVII. FIRE AND MINE COMMANDS. THE FIRE COMMAND. 249. Mannir^ parties for a fire commander's primary and second- ary stations. Primary station: Fire commander. Communication officer. Electrician sergeant. Observer. Reader. Recorder. Operator for each telephone. Operator for each searchlight controller. Plotter, assistant plotter, and two arm setters, when plotting board is used. Orderlies. Secondary station: Observer. Reader. {C.C.A.D.R.No.l.) 250. Fire commanders will be assigned to fire commands by orders from coast defense headquarters. 251. The fire commander is responsible for the drill and the tactical efficiency of his fire command. 253. His duties will be confined to those affecting the tactical efficiency of his command. 253. Normally, he controls his command from the fire com- mander's station, but when necessary may go wherever his presence is required. 254. He wUl be responsible that the fort commander is informed as to any deficiency of equipment or supplies. 255. If a field officer, on days of battery drill, he will visit the batteries of his command, and on days of indoor instruction, the companies of his command during the instruction period. 256. He will require a thorough knowledge of the installation, equipment, system of fire control, and drill on the part of the officers of his command, will encourage efforts for the improvement thereof, and will require the system of commands prescribed herein to be used. 257. The fire commander will have the assistance of a staff officer, who will be called the communication officer. The com- munication officer will have charge of the system of communica- tions and of the fire commander's manning party. In case an officer is not available, a noncommissioned officer (preferably a sergeant major) will be so aasigned; 106 FIRE AND MINE COKMAKSS. 258. The communication officer will inspect the equipment of the station, will receive the reports of the chiefs of detail, and will report to the fire commander: "Sir, F' (or F") in order," or will report defects he is unable to remedy without delay. 259. Each member of the manning party on reaching his station will examine the apparatus to which he is assigned, will make the prescribed tests and adjustments, and will report to his chief of detail. On completion of the examination, each chief of detail at the primary (and secondary) station will report to the communica- tion officer: "Sir, F' (orF") in order, or will report defects he is unable to remedy without delay. 260. The fire commander will indicate a target to his observers as follows: 1. Target. 2. Name of one of the subareas into which the battle area is divided by the coast defense commander . 3. Name (or type and class) of an isolated ship, or designation of division, formation, ship number , or in ' ' number of covering illuminating light, ' ' or any sufficient descrip- tion. If, in the judgment of the fire commander, a target can not be sufficiently indicated to the battery commander by description, it may be tracked for two or three observations and its predicted position for a convenient interval ahead located. This predicted position is relocated for the battery by means of the pantograph attachment of the F' plotting board, when provided, and the relocated range and azimuth sent to the battery commander's station. The fire commander's instrument is set to the predicted azimuth and "now " called over the telephone as the target crosses the vertical wire. Indication and identification of targets by means of a system of squares is also authorized. (C C. A. D. R. No. 1.) 261. The fire commander will control the searchlights assigned by the fort commander as illuminating lights for his fire area. 262. When ordered by the fort commander to assume the exercise of fire commander's action, or when for any reason the fort com- mander's station is not manned, or when communication therewith is interrupted, he wiU fight his command in accordance with the general plan of action. He will order "BATTERY COMMAND- ER'S ACTION" whenever the progress of the attack renders such action advisable, provided "FIRE COMMANDER'S AC- TION" has been previously ordered by the fort commander or when emergency renders its necessaiy. 263. In exercising fire control, the fire commander will deter- mine the order of fii'e for his batteries. 264. In giving commands to his batteries, the fire commander will proceed as follows: First. ALL BATTERIES (or name of any battery or batteries, as EUSTIS, or EUSTIS and CHURCH), TARGET, will signify that a target is to be assigned and will have the effect of calling the par- ticular battery or batteries to attention. Second. The name of one of the subareas into which the battle area is divided by the coast defense commander. When the sub- area is designated, all observers concerned wiU turn their instru- ments in the general direction of the target. At night, in addition to the subarea, the number of the searchlight which is covering the target will be given. FIRE AND MINE COIfMANSS. 10? Third. Deeignation of target. That is, name (or type and class) of an isolated ship; or designation of division, formation, ship number , or any sufficient description. Note. — Ships in line are numbered from the starboard ship. Ships in column are numbered from the leading ship. Fourth. The order of fire desired COMMENCE FIErNG. hbe when in bangs. jibe when at yabds. fire bounds, commence firing. fiee at inteevals, commence fming. fire on salvo point no. . fire at ships in order in column, commence FIRING. (This requires fire to be opened on the leading ship, continuing until disabled, or until the fire commander commands TARGET OUT OF ACTION, then chang- ing to the next ship in column.) FIRE AT SHIPS IN ORDEB IN LINE, COMMENCE FIR- ING. (This requires fire to be opened on the starboard ship of the line, continuing until disabled, or until the fire com- mander commands — TARGET OUT OF ACTION, then changing to the next ship in line.) (C. C. A. D. R. No.l.) 265. The following commands are given as examples: (Dashes indicate pauses.) 1. ANDERSON . TARGET . 2. BUCEHOE . 3. TEXAS . COMING IN . 4. FIRE WHEN IN RANGE. 1. WHEELER . TARGET . 2. BOCA CHICA . 3. on. TANK . CLASS 1-3. GOING OUT . 4. FIBE TWO BOUNDS . COMMENCE FIBING. 1. PARBH . TARGET . 2. TABOGUtLLA . 3. SUBMARINE DIVISION . SHIP NO. 3 . 4. COMMENCE FIRING. 1. MERRITT . TARGET . 2. PANAMA . 3. BATTLE CBUISEB DIVISION . 4. FIBE AT SHIPS IN OBDEB IN COLUMN . COMMENCE FIBING. 1. MONTGOMEEY . TABGET . 2. BUCKBOE . 3. DESTBOYEE DIVISION, DOUBLE UNE . SECOND LINE . SHIP NO. 2. . 4. FIBE WHEN AT 7,000 YABDS. 266. A column formation can frequently be simulated at drill by a tug towing barges or targets. In such case, the barges or tar- gets will be numbered from head to rear, thus: 1. CHUBCH . TABGET . 2. OCEANVIEW . 3; COAL BABGE DIVISION GOING OUT . SHIP NO. 1 (the towing tug) OB BABGE NO. 2 (second barge) . 1 EUSTIS . TABGET . 2. LYNNHAVEN 3. MILLS DIVISION . TABGET NO. 2 1 PABBOTT . TABGET . 2. HOBSESHOE . 3. SAND DBEDGE DIVISION . DEEDGE NO. 108 FIRE AND MINE COMMANDS. 267. No system of commands can cover all cases, but th.e lorm of commands prescribed herein will be considered as typical and will be followed as closely as practicable. 268. Other commands which may be given are as follows: CEASE FIRING. — This reqviires firing to cease instantly. CHANGE TARGET. — This requires firing to cease instantly, but requires all battery commands to be in readiness to identify a new target. CLOSE STATIONS. — This indicates that all battery commands and the fire commander's manning party are to be dismissed. The senior chief of detail at each station will see that the instruments are secured and covered, that the switches controlling the electric circuits are left open, and that the windows are closed and fastened securely. THE MINE COMMAND. 269. Manning parties for the mine commander's primary and secondary stations : Primary station — Mne commander. Assistant mine commander. Observer. Reader. Recorder. Searchlight operator. Operator for each telephone. Plotter and two arm setters. Orderlies. Double primary station — Double the above, except mine commander and orderly. Secondary station — Observer. Reader. Double secondary station — Double the above. (C. C. A. D. R. No. 1.) 270. The mine commander is in command of the elements of the mine defense. He is responsible for the drill, instruction, and tactical efficiency of his mine command, and bears the same rela- tion to the fort commander as do the fire commanders, and his duties are similar to theirs. S71. His duties will be confined to those affecting the tactical efficiency of his command. 272. He takes station at the mine primary or at such other place as his duties may require. 273. He is responsible that the property ofiicer requests for all material and apparatus necessary to carry out the approved scheme for submarine mining of his mine command, and that this material and apparatus is kept in proper condition for immediate service. 274. The mine commander, with the approval of the coast de- fense commander, will designate an officer of the mine command as mine property officer. The mine property officer will obtain from the artillery engineer all material and apparatus necessary FIRE AND MINE COMMANDS. 109 for the mine defense. He will have direct charge of the store- room, cable tanks, loading room, wharves, boats, boathoiises, and mining casemates. The perBonnel of the mine command are subject to the orders of the mine commander for service under the mine property officer for the care and preparation of any of this materiel. 278. The mine commander supervises and conducts the fire of the batteries of the mine command in the same manner and by similar commands as are used by fire commanders for the batteries of their fire commands. Chapter XVIII. THE FORT COMMAND. 276. Manning party for fort commander's station: Fort commander. Personnel officer. Materiel officer. Master electrician or electrician sergeant. Observer. Reader. Recorder. Operator for eacli telephone. Operator for each searchlight controller. Orderlies. (C. C. A. D. E. No. 1.) 277. A fort command consists of all the means of seaward and landward defense, including personnel and mat^el, located at any coast artillery fort. 278. The fort commander is responsible to the coast defense commander for all matters affecting the efficiency, instruction, dis- cipline, and appearance of the personnel, and the service, care, and preservation of materiel of his command. 279. He coordinates the seaward and landward defense. Through the fire and mine commanders, he controls the seaward defense; through the support commander, he controls the landward defense. 280. When two or more fort commands cover the same water area, the seaward defense for that water area will be controlled by the senior fort commander of those fort commands which cover that area. 281. The tactical station of the fort commander will be desig- nated by the coast defense commander with the approval of the War Department, and announced in orders from coast defense headquarters. Whenever, in the exercise of his duties, it becomes necessary for him to leave his station temporarily, he will turn over the direction of the seaward defense pertaining to his fort to the next senior coast artillery officer present for duty at the fort; if necessary, he will direct such officer to take station for that purpose at the fort commander's station. 282. He will require a thorough knowledge of the installation, equipment, system of fire control, and drill on the part of the officers of his command, will encourage efforts for the improvement thereof, and will require the system of commands prescribed herein to be used. 283. The fort commander will have two officers to assist him in the performance of his duties; these will be designated "Personnel officer" and "Materiel officer." 284. During drill, practice, and in action the personnel officer will have charge of all fire-control communications of the fort command and will transmit the orders of the fort commander. In TBE FORT COKMAKS. Ill preparing for drill, practice, or action he will inspect all of the equipment of the fort commander'a station, verify the adjustment of the position finder, and satisfy himself that the telephone gystem of the fort command is in good working order. He will report to the fort commander the fact that the station and communication system are in order, or will specify such defects as he may not have been able to remedy himself. 286. The materiel officer will have charge of the light and power service of the fort command and, during drill, practice, or action, of the manning parties assigned thereto. He will be responsible to the fort commander for the efficiency of the communication, light, and power service of the fort command. 286. All repairs, defects, or deficiencies pertaining to the arma- ment and its accessories will be reported to the materiel officer, who will have them made, corrected, or supplied, if practicable, by means available at the fort; otherwise he will report them to the proper coast defense staff officer. 287. Prior to drill or action the materiel officer will satisfy him- self by inspection or inquiry through the telephone service that the power and? light system is m efficient condition. To this end, he will receive ^e reports of those in charge of the several power and light units, and when reports shall have been received he will report to the fort commander that the power and light systems are in order, or, in case any defects are reported that he Ib unable to remedy without delay, he will report such defects to the fort com- mander and will take steps to have them remedied at the earliest practicable time; if necessary, reporting them to the proper coast defense staff officer. 288. Each member of the fort commander's detail on reaching his station will examine the apparatus to which he is assigned, will make the prescribed tests and adjustments, and will report to the personnel officer, "Sir, Lq order," or will report defects he is unable to remedy without delay. 289. The fort commander will indicate targets to his observer by commands similar to those provided for fire commands in Chapter XVII. He will study the battle area, and will consider the location and strength of the elements of the defense under his command, and will rehearse the forms of attack liable tt* be adopted by an enemy. While it is not practicable to anticipate all of the conditions of attack that may arise during an engagement, nor all of the methods of attack that may be employed by an adversary of initiative and resource, there are certain type forms which may be anticipated and which will be frequently rehearsed. 290. Before becoming committed to any form of defense he must understand the intentions of his opponents and consider the differr ent courses of action open to the defense, with the advantages and disadvantages of each, and rapidly arrive at a clear and defijoite decision as to the best method of defense. 291. In giving his commands to his fire or mine commanders he will proceed a s fol lows: Fust. ALL FIKE COMMANDS, or Fi, (Fj, Mj, etc.), TAB- GET, will signify that a target is to be assigned, and will have the effect ■ 1 i i ^''^^1 2 1 I 5 ' ^^H 1 ^^^^4 1 w m T fv m M- i . ! T "^ 00 bX) APPARATUS— FIRE CONTROL AND DIRECTION. 141 clamped to both bars, locks the whole system and is called the locking pointer. To expedite operation, outside pointers are alternated as the locking pointer. All other pointers are clamped to the fixed bar. The provision for locking to both bars serves two purposes; first, to provide against shifting the pointer when passing from one clamped position to the other; and second, to prevent the system from getting out of adjustment. The gear system is designed to move by turning the knob, the pointers carried on the movable bar and the movable range scale simultaneously, the former moving twice the distance of the latter. The displacement of the latter records the aggregate motion of the pointers. The knob must never be turned, except when adjusting, while all four pointers are clamped to the fixed bar. One end of each sprocket chain is attached to the counterweight. Both chains pass up through the middle of the top of the box, separate, and each passes over two sprocket wheels, thence down through the top of the box, and each is attached at its other end to an end of the correction ruler. The ruler can be moved up or down immediately in front of the correction chart and will remain at any position to which it is set. Adjustments. — There are two adjustments for the range board. First. Vertical adjustment. With the adjusting screw on one of the sprocket chains, set the two fixed indexes at the same range on the vertical scales on the correction chart. Second. Horizontal adjustment. Clamp the locking pointer to the movable bar. Turn the knob of the gear system until the pointer is exactly opposite the normal of its set of correction curves. Clamp this pointer to the fixed bar. In like manner set each of the other pointers to the normal of its correction curve and clamp to the fixed bar. When all four pointers are at their normals and clamped to the fixed bar, turn the knob until the movable index indicates the same range on both movable and fixed range scales. Clamp one outside pointer only to both movable and fixed bars, locking the system. Operation. — Set each marker at its proper correction curve. Set the movable Index at the range to the seWorward point on the fixed range scale. Set the fixed indexes of the correction ruler at the range of the set-forward point on both vertical range scales of the correction chart. Clamp the locking pointer to the movable bar, and by means of the knob, set this pointer at the correction curve indicated by this marker. Then clamp to the fixed bar. Proceed in like manner with the other pointers in succession, locking the system with the last outside pointer used. The range on the movable scale at the index under the reading glass is the corrected range. The range board operator transmits this corrected range to the gun emplacements. Note. — In operating the range correction board, it is not neces- sary to return any pointer to the normal of its set of correction curves. It is necessary only, to set the ruler and index at the range for the set-forward point, and move each pointer directly to its proper correction curve. The correction curve is frequently imaginary, and lies between two of the plotted curves in which 142 APPARATUS— FIRE CONTROL AND DIRECTION. case the pointer is set on the imaginary curve, as indicated by the marker. Test of accuracy. — There are two tests for accuracy, viz: For mechanical accuracy: Use each set of test points marked on the correction curves and on the same range line and determine the corrected range. The true corrected range corresponding to each set is shown in brackets on the margin. Repeat several times for each set and record the difference of each determined range from the true range. The mean of these differences is the mechanical error. An officer should conduct this test, exercising the utmost care in operating the board. For accuracy of the range board operator: Direct method. — The range board operator uses the test points with the index covered . Reverse method. — After a series of corrected ranges have been determined by the range board operator, the range officer will set each pointer at the normal of its set of correction curves. The differences in ranges on the two scales under the index in excess of the mechanical error will be due to inaccurate work on the part of the range board operator. Other methods of test may be devised if found desirable. Homenclature. 1. Bo:c (mahogany). 13. Pointers. 2. Chart frame. ' 14. Clamp. 3. Canvas chart momit. 15. Fixed indexes. 4. Correction chart. 16. Movable index. T). Bar for markers. 17. Reading glass. 6. Markers (curve indicators). 18. Chain. 7. Correction ruler. 19. Chain sprocket. 8. Fixed bar. 20. Chain adjusting screw. 9. Movable bar. 21. Clamping screw. 10. Fixed range scale. 22. Counterweight (concealed by chart 11. Movable range scale. frame). 12. Knob. aANGE BOARD FOB GUHS OF MINOR ARMAMENT. 395. This is shown in figure 9. Description. — Two fixed scales (g) and (h), one movable scale (/), and index (c), a runner (d), which carries an index wire (c). Operation. — Battery commander determines range correction and calls it to range keeper, who moves slide "a" until range cor- rection index indicates this correction on range-correction scale. (Range-correction index must be kept set at last range correction given range keeper by battery commander.) Range keeper then slides runner until range-index wire indicates range on "g" called from range finder; he then reads range on " f," indicated by range- index wire, to operator of mechanical transmission device. TELESCOPE. 398. Figure 10 illustrates the important parts of a telescope. A telescope is a deUcate piece of apparatus and reCi^uires careful use. It should never be subjected to unnecessary shock. When not in use it should be kept in the case provided for it or protected b Under-cvf qro0ve C Ccrrccfion 'triden Q' Runner € Rariae }nt/c» wft f Correcfecf ranges y Acfvaf rah^es (i Ranat corrtcfiOn 4ca/e § s I i %\ \ % \ I i % \ \ % % \ I \ % I r\ \ \ \ \ .a t' ll ii lll llll il ll llilli m iiliiiliiiiiiiiiiiiiliui . I Actual ?-"H?«i Ranges r I f Cori-ecfed « ^ f /( ! « -Do-r. Range correction " Scale Fig. 9. 104227°— 17. (To face pago 142.) •Section on /I'ne AB •Sca/e, tin ' 200 y da us. 144 APPARATTTS — FIIIE CONTROL AND DIRECTION. by proper covers. Pai-ts liable to rust should be kept ligbtly oiled; bronze parts should be kept clean and dry. To obtain satisfactory vision absolute cleanliness of the lenses is necessary, and they must be kept free from moisture. Chamois skin or a clean linen hand- kerchief may be used to remove moisture or particles of dust, care being taken that the lens is not scratched by grit or dirt. The lenses will require cleaning on the inside infrequently, aiid when this is necessary they should be removed by a competent person. The object glass must be kept screwed home at all times. Erecting prisms, if found in the telescope, should never be removed from the prism holder, nor the objective lenses from the objective cell and ring. If they need repair, report should be made to the proper authority. When the eyepiece of a telescope is removed, the cross wires are generally exposed in the tube. They are very delicate and must not be touched. In the use of a telescope for coast artillery purposes, two adjust- ments are necessary: 1. The focusing of the eyepiece so that the cross wires appear clear and distinct; this should be done by pointing the telescope to the sky. It should not be done with any near object in the field of view. Generally the cross wires have more or less roughness on them, which is most clearly seen when the eyepiece is focused properly. Another way of testing this adjustment is to see whether or not the ends of either cross wire appear double or blurred. If so, the adjustment is not perfect. 2. The focusing of the objective so that the object appears clear and distinct. The proper position of the objective to obtain this result will be found most readily by moving it in and out a few times past the proper point. When the image appears to be satis- factory as to clearness the head should be moved from side to side or up and down as far as possible, keeping the ima§e still in view. If the intersec tion of the cross wires appears to remain upon exactly the same point on the object, the focusmg is satisfactory! otherwise not. Tlie adjustment should be repeated until this result is obtained. Apparent motion of the cross wires on the image, due to faulty focusing of the object glass, is spoken of frequently as "parallax." The parallax must be eliminated before satisfactory work can be accomplished. 3. Usually the collimation of the telescope will be correct, but if necessary to adjust it for collimation, the telescope should be leveled and the intersection of the cross wires brought on the target, some well-defined object being used. The telescope is then inverted; that is, turned upside down. If the intersection is not then on the same part of the target, one-half of the discrepancy should be corrected by means of the radial screws in the objective cell ring. The telescope should then be inverted, and the opera- tion repeated until the cross wires remain on the target when the telescope is inverted. The collimation is then correct. Before attempting this adjustment the telescope should be carefully focused. On some instruments this adjustment is impracticable and the collimation is assumed to be correct. ' APPARATTIS— FIRE CONTROL AND DIRECTION. 145 TELESCOPIC SIGHT. 397. See Ordnance PampWets 1952, 1955, 1956, 1958, and 1959. The telescopic s^ht is attached to the gun carriage, so that its axia may be adjusted to intersect the axis of the gun at or beyond mid-range. Normally it is used to give direction to the gun, the deflection being set on the sight by means of a horizontal scale graduated from 0° to 6° — tlie 3° point being in the vertical plane containing the axis of the telescope. On some carriages the sight is mounted so that it may be used to give elevation as well as direction. See Telescope. THEKMOMETEB. 398. In locating the thermometer in or near the meteorological station, the following should be'borne in mind: First. The temperature of the outside air is required and not the temperature of the station. Second. The thermometer must be in the shade to obtain the temperature of the air. Third. The thermometer should not be located .where it can he affected by radiation from the walls of the station or by artificial heat from any source. Fourth. The thermometer should be placed where it is exposed to a fair circulation of air and protected from the sun and rain. Great accuracy in the determination of atmospheric data is not necessary. Temperature is the most important; a change of 5° has about the same effect upon the range as a 10-mile longitudinal wind; five-tenths of an inch is a corresponding barometric change. TIME-nrTERVAL SYSTEM. 399. See Signal Corps Manual No. 8. TIUE-HAITGE BOAKD. DESCRIPTION. 400. The time-range boai'd consists of a blackboard approxi- mately 9 feet by 6 feet in exterior dimensions, over which a T square slides. It is ruled as shown in the accompanying diagram, the vertical lines representing time lines and the horizontal lines representing range lines. The distance between full range lines is 100 yards and the distance between fujl and broken range lines is 50 yards. The interval between full time lines is 30 seconds, and this interval is subdivided into 10-second intervals by dotted lines. The T square is constructed as shown in figure 11. Thedimensions of the head "b " are about IJ by 5 by 30 inches. It is screwed to the leg " m " and is beveled on the lower edge. It slides on the support "a," and in order to reduce friction to a minimum is provided with a number of friction clips on the lower edge. 104227°— 17 10 146 APPARATUS— FIEE CONTROL AND DIRECTION. ■'l'_. - - ■ ( ■ r -t- i "f; ...i-- -r- — I — -••j-— .1... i ~T" ...4.... ■■•i"" -1- •■•|- ...-j.... „i...- -i- i -■H--" .-.;..._ ...4-. i — ;-■- ..|.. ...|... — f" ....[.- .4.- ....!.... ...4..., T .. .!-■•- J ...i— ...i... ....;... •■•-:■- ...;... "'l"" ...i.... i o ••■;•■•• ...i... j ■— j— . '--i- — j CD UJ u _.4— . """:'" ...i... ...-i... f- ...j... ,.4.._ . — i — F... .... -;■•■■ •-;•- ■-]■■■■ f— • ...j... ...|... "4- ; ■"t" h o ■[ ■ -T- ...;... •c : i i- ...^-.'.1. 1 — "i— i t? i lii^lir iS lih^il iiHiiii, \ III il... -,r ...i... :-* ....j.,- J —■--.. : --" { ^ ....,..- ! : j ■ ...L... -i- ""['" 30NVd to APPARATUS— FIRE CONTROI AND DIRECTION. 147 The support "a" is about SJ inches wide and IJ inches thick. It is screwed to the time-range board, and is beveled on the upper edge. The adjusting piece "c " is about IJ by 2 by 30 inches. On the top edge of "c " there are a number of friction clips which are in light contact with "a." The piece "c" carries two bolts which fit in the grooves "d." The bolts are provided with wing nuts which can be used for the purpose of adjusting "c" in position against "a." By unscrewing the wing nuts, the piece "c" can be lowered, and the T square can be removed from the time-range board. The leg is composed of two pieces "m" and "n," each about 6 inches wide and IJ inches thick. In order to keep the lower piece "n" from scraping on the time-range board, there are two friction clips placed on the underside of the leg and near the bottom, "m is screwed to "n," leaving enough space above "n" for "c " to be lowered out of the locking position. The range scale is painted on the leg as shown in the diagram. The figures in the thousandth and hundredth digits are left blank until written in by the range recorder in chalk. These thousandth and hundredth digits are recorded and removed at will by the range recorder, as may be necessary. The pointer slide "s" consists of a pipe T, to which is fitted the steel spring "g" and the subpointer "k." The slide, capable of moving up and down the metal rod "e,"' is held in position at any point of the rod by the action of the steel spring "g." The rod e" is about one-fourth inch in diam- eter, and is attached to "n" as shown in the diagram. The pointer "p" is screwed into the T, and is adjusted so that the distance from the right edge of the leg of the T square to the end of the pointer is equal to the time interval representing the average time required to set the range and to fire the gun, reckoned from some convenient starting time. (For guns mounted on dis- appearing carriages, the command TRIP is taken as the starting tune.) A stop watch "h"' (kept running with the time-interval bell) is hung at some convenient point on or near the T square. OPBHATION. (a) Normal method with T siiuare. — When the first range is received by the range recorder (usually about 20 seconds after the instant of observation) he plots the range by a cross (X) in chalk on the first time line on the left of the board, opposite the proper point on the range scale. This marks the corrected range of the set-forward point for about 10 seconds ahead. Sim- ilarly, the second range, when received, is plotted by a cross in chalk on the second time line. A full chalk line is drawn joining the two cross marks, and is prolonged' by dots until the dotted line intersects the third time line. This plotting process continues as successive ranges are received by the range re- corder until the last time line is reached, or until the plotted time-range line runs off the board, when the range is immediately 148 APPARATTJS— FIRE CONTKOL AND DIBECTION. transferred back to tlie first time line on the left and near the top or bottom of the board (making the necessary changes in thou- sandth and hundredth digits on the range scale), and the process is then continued as just described. The successive plotting of ranges should form a regular curve, the ordinates of which give the corrected ranges of set-forward points for any time of firing. The rate of increase or decrease in range is shown by the curve in such a manner as to be easily noted. Any range error made by the range section is revealed by a sharp break in the regular time-range curve. When such sharp break appears, the range recorder indicates the location of the point on the board by a small circle instead of a cross, but rejects it as a point of the time-range curve and continues the regular curve in a dotted line until it is ascertained precisely whether the break was due to an error or to a sudden change in the course of the target. In the case of guns mounted on disappearing carriages, when the range recorder hears the command "TRIP," he notes the time on the stop watch to the nearest five-second mark and sets the T square so that the right edge of the leg is adjusted to the time noted. He then moves the slide so that the end of the pointer touches the time-range curve. The subpointer now indicates the corrected range of the set-forward point for the instant of firing, and the range setter uses this range for setting the gun-range scale. After the T square and subpointer are set they are not moved until after the command "READY," has been given. No range is set on the gun-range scale until the command ' 'TRIP. ' ' Aftf-r the gun commander notes whether the gun goes fully into battery, he verifies the range setting. In case the range setting is wrong, he causes the range setter to correct it instantly and, if necessary, requires the range recorder to reset his T square. 'After verifying the setting, the gun commander calls "READY," and the gun pointer fires the gun, or, if friction primer has to be used, gives the command "FIRE," as soon thereafter aa the gun is pointed. In case of guns mounted on barbette carriages, the operation is the same except that the T square is set on a selected starting time instead of at the command "TRIP," and the gun commander does not verify the range. The range recorder stands in such position as will not interfere with the range setter's seeing the range indicated by the subpointer. (6) Alternative method without T square. — ^The following method" of using the time-range board without the T square is authorized: The time-range curve is plotted aa prescribed in (a). In this case, the ranges are placed on the time-range board instead of on the T square. At a selected starting time (for example, the command TRIP) the range setter (or some other member of the gun section to be designated by the battery commander) takes from the time-ranee curve the corrected range of set-forward point which will be the correct range setting if the gun is fired a certain definite number of seconds after the starting time (for example, 15 seconds), "rins range is set on the gun-range scale. APPARATUS— FIBE CONTROL AND DIRECTION. 149 The gun commander notes .whether the gim goes fully into battery, verifies the range setting, and calls "READY" in time for the gun to be fired at the time corresponding to the range setting. In case of a delay so that the gun can not be fired at the correct time, a new range for a definite number of seconds ahead is taken from the time-range curve. Under the authority contained in paragraph SOB, when the time range board in the emplacement is not used, ranges are transmitted to the range setter from the time range curve in the plotting room at regular intervals or may be sent only when called for by the raiige setter. (C. C. A. D. R. No. 1.) WIND COMPONENT INDICATOR. (See Ordnance Pamphlet 1794.) 401. The object of this device is to determine the wind refer- .ence numbers to be used on the range and deflection, boards and to indicate the-numbers to the operators of these boards. It consists oif a circular dialjJA), flgm-e 12, on the face of which the reference numbers are marked with corresponding horizontal and vertical lines. The dial is intended to be held in a vertical position by means of a bracket (M) Screwed to the wall and fastened to the back of the dial in such a way that the dial itself wiH not turn; hence the figures it carries will be right side up always. Around the dial is the movable azimuth ring (B), graduated and numbered clockwise every 5°. This ring can be set, so that the wind azimuth pointer (K) at the bottom of the dial points to any •'req\iir6d' wind azimuth. The ring can be clamped in position by a clamp screw at the -back of the plate immediately behind the wind azimuth index. Embracing both dial and ring and rotating about an axle at ithe back of the dial ia the target arm (C). The target arm is centered - in front by the screw (D), which passes through the end of itinto the center of the dial. It has a clamp screw, by means of which it may be clamped atany desired azimuth, indicated by the azimuth ..index (C). The pointer (HH') passes through a slot in the square projection on "the end of the targ;et arm and can be set to indicate any wind velocitj? from to 50 miles per hour by ineans of the wind scale on tlie target arm, using the end (H) of the pointer as an index. The reference .numbers to be used on the range and deflection boards are indicated "by the end (H') of the pointer. The instrument is intended to be suspended from the ceiling immediately over the plotting board and facing the range and deflection boards^ so that the operators, of these boards can read the. range and deflectibn components without leaving their positions. _ The operator sets the pointer (H) to the wind velocity, and by turning the azimuth ring brings the wind azimuth to the pointer (K). He keeps the target arm set to the approximate azimuth to the target, as indicated by the gun arm, using the index (0) and moving the target arm as the target moves. Should the wind change in velocity or direction, he makes the corresponding change on the board. 160 APPARATUS— FIRE CONTROL AND DIRECTION. Fig. 12. APPARATUS — riaE CONTROI AND DIRECTION. 161 WIND VANE. 402. This ia a device for determining tHe direction of the wind. It should be ren[iembered that the mean direction of the wind is desired. The ordinary fluctuations in direction are due usually to local causes near the surface of the earth and have but little effect upon the flight of the projectile. A true fish-tail wind undoubtedly produces varying results, but it is not practicable to do anything other than consider its mean direction. ' The observer should wafch carefully the movement of the vane an . J . Testing sets For guns,, carriages, projectiles, and . position-finding instruments. 'Do. Do. . For recoil cylinders, gun carriages. For guns and carriages. For cleaning recoil cyhnders and guns. For removing old paint from the guns, carriages, .sights, position tinders, and for cleaning and polishing bright inetallic surfaces. • For gim covers. For mech&nic^l maneuvers. For battery charts. For recording firing data at emplace- ments. For cleaning, painting, and ,packlng guns and carriages, and position find- ers, etc. For storage of oil at batteries. Foi: cleaning recoil cylinders. For weighing powdei; ^d projectiles. For testing cartridge storage cases and" ■ metal-lined boxes. 154 CARE OF MATERIEt. For detailed information in regard to allowance of materials enu- merated above, see Ordnance Pamphlet 1869 and drawing 27-5-1 of latest revision. In case of conflict between pamphlet and draw- ing, allowances as shown on drawing will govern. 410. The Signal Corps supplies the following: Fire control apparatus pertaining to communications, time- interval system, signaling, and meteorological data. It supplies field glasses, portable ammeters and voltmeters, all cable for communications. 411. The Quartermaster Corps supplies the following: Furniture (except floor covering or circular benches for fire control stations), stoves, scythes, sickles, shovels, rakes, fuel- handling apparatus, fire tools, wheelbarrows, etc. For power and electric plants maintained by the Quartermaster Department: Paints, fuel, lubricating oil, kerosene, oil-storage tanks, spare parts (for engines, generators, boilers, and accessories), brooms, Sapolio, brushes, soap, mops, sal soda, and waste. For police of fire-control stations: Brooms, Sapolio, brushes, soap, mops, sal soda, and waste. REGULATIONS PERTAIOTNG TO ENGINEER DEPARTMENT PROPERTY AND INSTALLATIONS. 412. Coast defense structures, and the grounds surrounding them whose limits are prescribed by fort commanders, will be kept in proper police. 413. All open drains or gutters will be carefully swept at least once a week, and the sweepings so disposed of that they will not be carried back by wind and water. 414. Under no circumstances will drains, gutters, sumps, counter- weight wells, etc., be used as places of deposit for sweepings, waste, rags, and other rubbish. Drains and sumps will be inspected weekly, and will be kept in good order. Water fixtures will be inspected weekly, and leaky fixtures will be promptly repaired to avoid waste of water and possible damage. 415. In freezing weather water will be shut off and pipes and fixtures properly drained at the valves provided for this purpose. 416. After rains, earth slopes and parapets will be inspected and any tendency to gully and wash will be corrected at once or will be immediately reported. 417. Walking on the earth slopes will not be permitted, except as may be necessary for their inspection, care, and repair. 418. Dry grass, weeds, etc., in the vicinity of structures that might increase the danger of fire will be cut and removed. 419. Before firing service charges, doors and windows in batteries and adjacent structures will be opened and properly secured, in order to minimize damage from blast. 420. All machinery, such as boilers, engines, generators, ptunps etc., will be kept in good working order at all times; electric lif. 676. The inspection at forts will be limited to seeing that the requirements for its storage and care are observed strictly. Chapter XXVI. DEFTNTTIONS. Note. — In this chapter will be found definitions of terms not found elsewhere in the book. To find any particular term see the Index. 677. Aiming. — See Pointing. 578. Ammunition. — ^A general term applied to projectiles, ex- plosives used for propelling projectiles, explosives used for filling projectiles, primers used for discharging guns and mortars, and fuses used for exploding projectiles. When the projectile, pro- pelling charge, and primer are held permanently together by a metallic case inclosing the powder and primer, or otherwise, in condition to be handled as a unit in loading, the ammunition is called "fixed ammunition." When the projectile, propelling charge, and primer are not so held together, but are handled separately in loading, the ammunition is called "separate-loading ammunition." 679. Ammunition truck. — A truck for carrying projectiles to the breech of cannon. 880. Angle danger. — See Danger angle. 581. Angle of departure. — ^The angular elevation of the line of departure above the line of sight. Quadrant angle of departure is the angular elevation of the line of departure above the hori- zontal plane through the muzzle of the gun in the firing position. (See fig. 15, par. 790.) 582. Angle of depression. — The angular depression of the line of sight below the horizontal plane. (See fig. 15, par. 790.) 683. Angle of fall. — The angle between the line of fall and the horizontal plane through the muzzle of the gun in the firing posi- tion. It is often represented by its slope; Tor example, 1 on 10. (See fig. 15, par. 790.) 884. Angle of impact. — The angle between the line of impact and the tangent to the surface at the point of impact. It is the complement of the angle of incidence. (See fig. 15, par. 790.) 685. Angle of incidence. — ^The angle between the line of impact and the normal to the surface at the point of impact. (See fig. 15, par. 790.) 586. Angle of jump. — The angular elevation of the line of depar- ture above the position of the axis of the bore at the time the piece was pointed. In determining the sight or quadrant elevation to be used, this angle must be subtracted algebraically from the angle 176 DEFINITIONS. of departure given in the range table; tlie angle of jump differs for different guns, carriages, and ranges, and is determined by- experiment. 887. Angle of splash. — See Danger angle. 588. Apron. — That portion of the superior slope of a parapet or the interior slope of a pit designed to protect the slopes against blast. 589. Axis of cannon or axis of bore. — The central line of the bore. 590. Axis of trunnions. — The central line of the trunnions. 691. Azimuth (of a point). — -In coast artillery usage, the hori- zontal angle measured in a clockwise direction from the south line through the observer's position to the line from the observer to the point. For example, the azimuth of a point B from A is the angle (measured clockwise from the south) between the north and south line through A and the line from A to B. The north point has an azimuth of 180°. 592. Azimuth difference. — The difference between two azimuths of a point as read from two other points, as, for example, the differ- ence in azimuths of a target as read from the primary station and from the directing point of the battery. 593. Ballistics. — That branch of the science of gunnery which treats of the motion of projectiles. Interior ballistics treats of the motion within the gun. Exterior ballistics treats of the motion outside of the gun. 594. Base line. — A horizontal line the length and direction of which have been determined . This line is used in position finding, especially for long ranges; the stations at its ends are called "ob- serving stations." It is called "right-handed" or "left-handed," depending on whether the secondary station is to the right or left of the primary from the point of view of a person facing the field of fire. The base end observing stations are called primary, sec- ondary, or supplementary. 595. Base ring. — ^The metal ring which is bolted to the concrete of the emplacement and which supports the weight of the gun or mortar carriage. 596. Battery. — One or more guns or mortars grouped with the object of concentrating their fire on a single target and of being commanded directly by a single individuil, together with the entire structure erected for their emplacement, protection, and service. 597. Battery parade.^The area in rear of the emplacements where the gun or pit sections form. 598. Battle area. — As applied to a coast defense or a fort com- mand, the area covered by the armament of the coast defense or the fort command, respectively. 599. Battle chart. — ^A chart used in fort, fire, or mine command stations, showing the water area covered by the armament of their respective commands. 600. Blending. — The process of mixing powders of the same or different lots so as to obtain charges of uniform characteristics. DEFINITIONS. 177 601. Bore. — The interior of a camion forward of the front face of the breechblock. It is composed of the gas check seat, the powder chamber, the centering slope, the forcing slope, and the rifled por- tion called the "main bore." The length of bore is the distance from the front face of the breechblock proper (not the mushroom head) when in position to the face of the muzzle measured along the axis of the bore. 602. Breech. — ^The mass of metal behind the plane of the rear section of the bore of a cannon, the section being taken at right angles to the axis of the bore. 603. Breechblock. — The metal plug which closes the breech of a cannon. 604. Breech bushing. — That part of the breech on the interior surface of which the threaded and slotted sectors of the breech recess are formed. 605. Breech, face of. — ^The rear plane of a camion perpendicular to the axis of the bore. 606. Breech mechanism. — The breechblock, obturating device, firing mechanism, and all parts used in operating the breechblock of a cannon. 607. Breech recess. — The opening in a cannon which receives the breechblock. 608. Breech reinforce. — The part of a cannon in front of the breech and in rear of the trunnion band. 609. Caliber. — ^The diameter of the bore in inches, measured between diametrically opposite lands. It is the minimum diam- eter of the rifled portion of the cannon. 610. Cannon. — ^Artillery weapons from which projectiles are thrown by the force of expanding powder gases. (See Gun or piece.) Gannon are of three classes: Guns, mortars, and howitzers. Guns are long (generally 30-50 calibers), have flat trajectories, and are used for direct fire (not exceeding 20°), with high velocities. Mortars are short (about 10 calibers), and are used for high-angle fire (above 45°), wilii low velocities. Howitzers are short guns and are used for curved fire (not exceed- ing 45°), with low velocities. Cannon of the Unites States land service are classified according to their use into coast, siege, field, and mountain. Built-up cannon are made by shrinking forgings (jacket and hoops) over an inner tube. Wire-wound cannon are made by winding wire under tension around a tube; a jacket and hoops may be shrunk over the wire-wound tube. 611. Cannoneer. — Any man employed in the "service of the piece." 612. Capital. — As apj)lied to an emplacement — ^the line through the pintle center bisecting the arc of the interior crest. As applied to a battery — ^the perpendicular to the line of pintle centers at its middle point. 613. Cap-square. — That part of a gun or mortar carriage which fits o/er the trunnion and holds the trunnion in the trunnion bed. 104227°— 17 12 178 DEFINITIONS. 614. Carriage or mount. — The means provided for supporting a cannon. It includes the parts for giving elevation and direction, for taking up the recoil on discharge, and for returning the piece to the firing position. 615. Carriage, fixed. — A mount provided for guns and mortars in permanent worlis and not designed to be moved from place to place. 616. Carriage, movable (wheeled mount). — A carriage or mount provided with wheels for transportation of the piece mounted thereon. 617. Carriages, seaooast. — ^Those used for coast artillery cannon. They may be divided into four classes, depending upon the nature of cover afforded by the emplacements. (o) Barbette : Where the gim remains above the parapet for load- ing and firing. Barbette carriages are used for guns of 3-inch or greater caliber. The pedestal mount is a type of barbette carriage used for guns up to 6 inches in caliber. (fi) Disappearing: Where the gun is raised above the parapet for firing and recoils under cover for loading. This mount ia used for guns of 6-inch or greater caliber. (c) Masking parapet mount. — Where the gun remains above the parapet for loading and firing but can be lowered below the level of the crest for concealment. This mount is also called the balanced pillar mount and is used for guns up to 5 inches in caliber: {d) Casemate. — Where the gun fires through a port. 618. Cartridge. — A complete load of fixed ammunition (projec- tile, powder, and primer) as used in small arms. 619. Cartridge bags. — Bags used to hold the powder charges for cannon. 620. Cartridge case. — A contabier in which powder is sealed for shipment and storage. 631. Case I, Case II, Case m. — See Pointing. 632. Centering slope. — The conical part of the bore between the powder chamber and the forcing slope. It is for the purpose of bringing the axis of the projectile in line with the axis of the bore. 633. Center of impact. — The mean position of the points of im- pact of the points of splash considered. . 624. Center of the target. — ^As used in coast artillery practice, the point from which deviations are measured. (See Deviation.) 625. Center, pintle. — See Pintle center. 626. Charge. — The explosive placed in a gun or mortar behind the projectile as a propellant (propelling charge). Also the explo- sive placed in the cavity of a projectile (bursting charge). 627. Charge (or powder) section. — One of the component parts of a charge when the charge is made up of two or more separate parts. 628. Chase. — That part of a cannon in front of the trunnion band. 629. Chassis. — That part of a gun carriage upon which the top carriage moves backward and forward. The chassis carries recoil rollers and the top carriage rests upon these rollers. DEFINITIONS. 179 630. Chord of the trajectory. — The straight line joining the ex- tremities of the trajectory, i. e., the straight line from the muzzle of the gun (in the firing position) to the point of splaeh. (See fig. 15, par. 790.) 631. Clinometei. — An instrument for measuring vertical angles with great accuracy; for example, the inclination of the axis of the bore to the horizontal. 632. Clinometer rest. — A device inserted in the muzzle of. a gun for the purpose of supporting a cUnometer; also called "bore plug" or "bore rest." 633. Coast artillery militia. — Troops of the organized militia organized as coast artillery for the purpose of supplementing the regular coast artillery in time of war. _ 634. Coast artillery supports. — Troops of the mobile army as- signed to coast artillery forts to repel land or landing attacks in the immediate vicinity of the fortifications. 635. Corridor. — ^The uncovered passageway in rear of a traverse connecting two adjacent emplacements. 636. Corridor wall. — The traverse wall along the corridor. 637. Counter-recoil buffers. — Devices on gun and mortar car- riages for the purpose of reducing the shock due to the return of the piece to the firing position. 638. Counterweight. — The weight used in bringing a gun on a disappearing carriage to the firing position. The pit in the gun platform for the reception of the counterweight is called the counter- we%ht well. 639. Crow's nest. — ^A recess on a parapet or traverse, used as an observing station. 640. Danger angle. — (Also called- angle of splash). The angle which the tangent to the trajectory at the point of splash makes with the plane containing the point of splash and parallel to the horizontal plane through the muzzle of the piece in the firing position. (See fig. 15, par. 790.) 641. Danger space. — ^The horizontal distance within which a target of a given height would be hit by a projectile. The danger space varies with the range, the flatness of the trajectory, the he%ht of the target, and the height of the gun above the target. The maximum range which is all danger space is called the " danger range. ' ' 642. Data line. — A telephone line used for the transmission of data. (See Intelligence hne.) 643. Datom point. — A fixed point, the azimuth and range of which, from one or more observing stations, have been accurately determined. 644. Deflection. — ^The angle between the plane of sight and plane of departure; it is usually expressed as a reference nxmiber, and is set off on the sight deflection scale. ; 645. Delivery table. — ^The hoist table from which the projectiles are delivered to the trucks. 180 DEFINITIONS. 646. Density of loading. — The mean density of the whole con- tents of the powder chamber. It is the ratio of the weight of the powder charge to the weight of a volume of distilled water at the temperature of maximum density (39.2° F.) which will fill the powder chamber. The formula for computing it is — /( (density of loading)=27.68 o/V in which ir is equal to the weight of the powder in pounds and V the volume of the chamber in cubic inches. 647. Deviation. — As used in coast artillery practice, deviations are either the horizontal distances of the points of splash from the center of the target, or the rectilinear coordinates of those distances. Deviations are measured in a plane passing through the water line of the target and parallel to the horizontal plane through the muz- zle of the piece in the firing position. (a) Absolute deviation. — The shortest distance between the center of the target and the point of splash. (6) Lateral deviation. — The distance between the plane of direc- tion and the plane of splash measured (right or left) from the center of the target and perpendicular to the plane of direction. (c) Longitudinal deviation. — The perpendicular distance (over or short) of the point of splash from the vertical plane passing thi'ough the center of the target and perpendicular to the plane of direction. (d) Mean lateral deviation. — The algebraic mean of the lateral deviations of a series of shots. (c) Mean longitudinal deviation. — The algebraic mean of the longitudinal deviations of a series of shots. (/) Mean absolute deviation. — The algebraic mean of the abso- lute deviations of a series of shots. (g) Range deviation. — The difference between the range to the target (at the instant the projectile strikes) and the range to the point of splash. The range deviation is equal to the longitudinal deviation when the lateral deviation is zero. 648. Deviation, azimuth. — The difference between the azi- muths from the directing point of the battery to the center of the target and to the point of splash at the instant the projectile strikes. 649. Difference chart. — A graphic device by means of which the range and azimuth of a target from one gun or station are obtained when the range and azimuth from some other gun or station are known. 660. Directing point. — A point at or near the battery for which relocation is made at the plotting room. It is the point for which the gun center of the plotting board is adjusted. When the pintle center of a gun is taken as the directing point, such gun is called the "directing gun." 651. Drift. — The divergence of the projectile from the plane of departure due to the rotation of the projectile and the resistance of the air. It is affected by the ballistic character of the projectile. It is in the direction of rotation and for the United States service SEFINITIONS. 181 rifled guns it is to the right. It may be expressed either in yards or degrees. 662. Electrician sergeant. — ^An enlisted specialist of the noncom- missioned staff coast artillery corps who is assigned to duty in con- nection with the electrical installations of coast artillery forts. 663. Elevating band. — A band around a gim near the breech to which are attached the elevating arms. By means of the ele- vating gearing, the elevating arms give elevation to the gun. 664. Elevation. — ^The incliiiation in a vertical plane given to the axis of the bore in pointing a gun; the angular elevation of the axis of the bore above the line of sight is the sight elevation ; the angular elevation of the axis of the bore above the horizontal is the quad- rant elevation. 656. Elevation table.— A table of ranges with corresponding quadrant elevation for a direct-fire gun on a mount provided with an elevation device graduated in ranges. The quadrant elevation."? tabulated in the elevation table are the angles of departure of the range table corrected for curvature of earth, height of sight, and jump. 666. Emplacement. — That part of the battery pertaining to the position, protection, and service of one gun, mortar, or group of mortars. 657. Emplacement book. — A book containing all necessary data concerning the battery. 658. Energy of the projectile. — The energy stored up in the pro- jectile by the force of the expanding gases generated by the explo- sion of the powder charge. It is expressed usually in foot-tons. The formula for computing it is — E=WV V (4480g), in which W is the weight of the projectile in pounds, V its velocity in feet per second, and g the acceleration due to gravity (mean value 32.16). V may be taken as the velocity at any instant and the energy remaining at that instant can be determined from the formula. 659. Engineer. — ^An enlisted specialist of the noncommissioned staS Coast Artillery Corps who, under the artillery engineer, is placed in charge of one or more power plants at a coast artillery fort. 660. Enlisted specialists. — Noncommissioned staff officers of the Coast Artillery Corps who are assigned to technical duties at coast artillery forts. The various grades are master electrician, engineer, electrician sergeant first class, electrician sergeant second class, master gunner, and fireman. 661. Eguallzing pipe. — A pipe connecting the front ends of two recoil cylinders for the purpose of equalizing the pressure therein. 662. iSrosion. — The gradual enlargement and scoring of the bore due to the action of powder gases on the metal of the lands and grooves. 182 DEFINITIONS. 663. Error. — As used in coast artillery practice, erroi-s are either the horizontal distances of the points of splash from the center of impact, or the rectilinear coordinates of those distances. Errors are measured in a plane passing through the center of impact and parallel to the horizontal plane through the muzzle of the piece in the firing position. (a) Absolute error. — The shortest distance between the center of impact and the point of splash. ( 6) Lateral error. — The distance between the plane of splash and a plane through the center of impact parallel to the plane of direc- tion, measured (right or left) from the center of impact and per- pendicular to the plane of direction. (c) Longitudinal error. — The perpendicular distance (over or short) of the point of splash from a vertical plane passing through the center of impact and perpendicular to the plane of direction. (d) Mean absolute error. — The arithmetical means of the absolute error of a series of shots. (e) Mean lateral error. — The arithmetical means of the lateral errors of a series of shots. (/) Mean longitudinal error. — The arithmetical mean of the longitudinal errors of a series of shots. 664. Error, probable. — The probable error of a gun in any direc- tion is that error which is as likely to be exceeded as not in the case of any single shot of a series fired with the same elevation and azimuth settings. This is equivalent to saying that in the long run 50 per cent of all shots fired with the same elevation and azi- muth settings will have an error less than the probable error. 665. Explosive. — ^Any substance by whose decomposition or com- bustion, gas is generated with great rapidity. Military explosives consist of solids or liquids which, through the application of heat or shock, are susceptible of being converted suddenly into gases through chemical reactions. 666. Exterior crest. — The line of intersection of the superior and exterior slopes. 667. Exterior slope. — The outer slope of the battery. 668. Field of fire. — The area covered b^ the armament of a battery, or with reference to a single gun, it is the area covered by that gun. 669. Fire area. — The area covered by the armament of a fire command. 670. Fire control. — Fire control is the exercise of those tactical functions coimected with the concentration and distribution of fire, including the assignment and identification of targets. 671. Fire control diagram. — A diagram showing the assignment of batteries to fire or mine commands, the di-vision of fort commands into fire and mine commands, the assignment of searchlights, and the system of communications for the tactical chain of command in any particular coast defense command. 672. Fire control installation. — The materiel as installed, which is employed in the fire control or fire direction of any unit, is called the "fire-control installation" for that unit. 673. Fire coutiol symbols. — The following symbolB are used in fire-control diagrams and for other purposes: Fig. 13.. Fort Commander's Station C ^ Primary Station.Fire Command F' @ SecondaryStafion.FireCommond F" [PI Supplementary Station, FireCommand F'" pj FVimaryStation.ofa Battery B' @ SecondaryStation.ofa Battery B" ^ Supplementary Station.ofa Battery B"' |b^ Battery Commander's Station B.C. @ FVimaryStation, Mine Command M' (^ SecondaryStation, Mine Command M" ^ Supplementary Station.Mine Command M'" Double P^-imaryStation.MineCommand M-M' @@ DoubleSecondaryStation.MineCommand M"M" |M"-|M"[ Separate Plotting Room P (?) Separate Obeerving Room (o) Emergency Station E (e) Meteorological Station Met. H Tide Station T Searchligtit S ^ Controller Bootti C.B. O Signal Station S.S. B Radio Station R. CabteTerminal C.Ter. @ FbstTeleptioneSwitctiboard RS.B. ^ Mining Casemate M.C. [■] Switct^board Room Swb. VA Powerhouse Rl^- ^ Central Powerhiouse C.P.H. IQj- 184 DEFINITIONS. Base line Telephone line (single). Telephone line (double). Speaking tube -q q q- Mechanical range transmission _| j .^ Electrical range transmission -^4 ^ i<_ Searchlight controller Mine loading room Zone signal line Firing signal line Time interval bell line . -© — i^ — — X — e — x^— e — ^ ' 9 ® & ® 9 • — M" !l£Jl Where the fort commander's station is a part of some other tactical station, one-half of the inclosing line will be doubled; for example, M'' and C combined. In general, where stations are combined in one room the letters representing each station will be inclosed in the symbol, for example : B.C. station and primary combined f •S.y j Primary station of a fii-e cciumand and plotting /pA room combined fp j Where stations are located in contact so that communication may be had by voice through a passage, door, window, or voice tube, the symbols for such stations will be tangent to each other, the circles will be left open at the point of contact, and will be so placed as to indicate the relative locations of the stations, for example : B. C. stations ^ '^^Vi "RO ' Plotting rooms ^ p (C. C.A.D.R.No.l.) 674. Fire direction. — Fire direction is the application of the methods and training necessary to secure accuracy of fire. A bat- tery commander exercises fire direction while the fire commander exercises fire control. 675. Fire discipliae. — The efiiciency of personnel in action, in- volving accuracy and alertness resulting from organization, drill, and combined practice. It is measured by the length of time required to exercise fire control and fire direction; the time re- quired to assign targets and to fire accurately. 676. Fire, kinds of: (a) Direct fire. — Fire with high velocities and with angles of elevation not exceeding 20°. (6) Curved fire. — Fire with low velocities and with angles of elevation not exceeding 45°. (c) High angle fire. — Fire with low velocities and with angles of elevation above -15°. DEFINITIONS. 186 677. Fireman. — An enlisted specialist of the nonconmuBsioned staff, Coast Artillery Corps, who under the engineer is assigned to duty for firing boilers, running engines, and other work in a power plant at a coast artillery fort. 678. Forcing slope.— The part of the bore inunediately in front of the centering slope. The rifling begins at the junction of the centermg slope and the forcing slope. The tops of the lands at this point are cut down so that less power is required at first to force them through the copper rotating band. The lands attain their full height at the front end of the forcing slope. • 679. Fort record book. — A permanent record book kept at each fort, containing the history of the works, their object, armament, scheme of defense, and all information of value regarding the equipment and installation. 680. From battery. — The po-sition of a gun when withdrawn from its firing position. 681. Fuse. — A device attached to a projectile for the purpose of causing the explosion of the bursting charge either by impact or at the expiration of a certain time of flight. Fuses are classified according to construction, as ring resistance, combination, time, and percussion, centrifugal, and detonating; they are classified according to location in the projectile as point and base. 682. Gallery. — ^Any passageway covered overhead and at the sides. 683. Gas check seat. — ^That part of the bore of a cannon where the gas check pad rests when the breechblock is closed. 684. Gun or piece. — ^A general term applied to any fitrearm from which a missile is propelled by the force of expanding gas. In a restricted sense, the term "gun" is applied as defined under "Cannon." 685. Gun levers. — Two steel arms on a disappearing carriage which support the gun at one end and the cotmterweight at the other end. The gun trunnions rest in trunnion beds on the gun levers, and the counterweight is suspended from a steel crosshead which joins the ends of the gun levers. The gun levers are pivoted near their middle upon a gun-lever axle which rests in bronze bushed axle beds in the top carriage. 686. Gunnery. — The art and science of operating guns. 687. Gun platform. — That part of the batt«ry upon which the gun carriage rests. 688. Harbor chart. — ^A chart showing the water area included in and adjacent to a fortified harbor. 689. Height of site. — The altitude of the axis of the gun trunnions in the firing position above the plane of mean low water. (See fig. 15, par. 790.) 690. Hoist room. — The room in a battery containing the receiving table of the ammunition hoist. 691. Hoop. — A forging superposed upon the jacket, tube, or other hoops of a cannon. 692. In battery. — The position of a gun when ready for thing. 693. Intelligence Une. — A telephone line used for the transmis- sion of orders and messages as distinguished from data. If prac- ticable, a data line should never be used for anything except data. 186 DEFINITIONS. 694. Interioi crest. — ^The line of intersection of the interior slope with the superior slope. If there be no interior slope, it is the line of intersection of the interior wall and superior slope. 695. Interior slope. — The inner slope of a parapet connecting the interior wall and superior slope. 696. Interior wall. — The inner parapet wall. 697. Jacket. — The principal forging shrunk on the breech end of a tube of a cannon. 698. Jump. — See Angle of jump. 699. Landward defenses. — Those portions of the defenses which are provided to repel an attack from the land area in rear of or on the flank of permanent seacoast works. 700. Line of departure. — The direction of the axis of the bore when the projectile leaves the muzzle of the gun. (See fig. 15, par. 790.) 701. Line of direction. — The straight line from the muzzle of the gun (in the firing position) to the center of the target at the instant the shot strikes. (See fig. 15, par. 790.) 702. Line of fall. — The tangent to the trajectory at the point of fall. (See fig. 15, par. 790.) 703. Line of impact. — ^The tangent to the trajectory at the point of impact. (See fig. 15, par. 790.) 704. Line of sight. — The axis of collimation of the telescope or the straight line passing through the sights of the piece; at the instant of firing this line passes through the center of the target. 706. Load. — ^A single charge of powder and a single projectile as combined for firing in a gun or mortar. 706. Loading platform. — ^That surface upon which the cannoneers stand while loading the piece. 707. Loading tray. — A device used to protect the breech recess while loading the projectile. 708. Lot. — A term used by manufacturers to designate a certain amount of explosive manufactured at one time. All of the explo- sive of one lot should possess uniform characteristics. 709. Machine guns. — Guns of one or more barrels using fixed ammunition and provided with mechanism for continuous loading and firing. The mechanism may be operated by man power or by the force of recoil. Guns in which the force of recoil is used to operate the breech- block are termed "semiautomatic." When this force is used also to load and fire the guns, they are termed " automatic." 710. Magazine. — A room for storage of powder, primers, or fuses, etc. 711. Maneuvering ring.— A large cast-iron ring embedded in the emplacement wall, and used in mechanical maneuvers. 712. Master electrician. — An enlisted specialist of the noncom- missioned staff Coast Artillery Corps who ia assigned to duty as assistant to the artillery engineer in connection with the electrical and power installations of a coast defense command. 713. Master gunner. — An enlisted specialist of the noncommis- sioned staff Coast Artillery Corps who is assi^ed to duty as assist- ant to the artillery engineer in connection with the preparation of charts, maps, drawings, range tables, etc., in a coast defense command. DEFINITIONS. 187 714. Mushioom bead. — ^The front part of the De Bange obturator. 715. Muzzle. — The front end of a cannon. The face of the muzzle is the front plane of the gun perpendicular to the a3d8 of the bore. 716. Muzzle or initial velocity. — ^The rate of travel in feet per second at which a projectile leaves the muzzle of a gun. 717. Obturator. — A device for preventing the escape of gas. Obturation is the process of preventing the escape of gaa. 718. Parade slope. — ^The rear slope or wall of an emplacement. 719. Paiados. — ^A structure in rear of a battery for protection against fire from the rear. It may have interior, superior, and exterior slopes. 720. Parapet. — ^That part of a battery which gives protection to the armament and persoimel from front fire. 721. Penetration. — This term used with reference to a projectile fired against armor signifies that the point of the projectile entered the armor but the projectile did not get all the way through. 722. Perforation. — ^This term used with reference to a projectile fired against armor signifies that the projectile passed entirely through the armor. 723. Piece. — See Gun or piece. 724. Pintle center. — The vertical axis about which a gun or mor- tar carriage traverses. 726. Pit.— That part of a mortar emplacement designated for mounting one or more mortars, usually two or four. 726. Plane of departure (also called plane of fire). — ^The vertical plane containing the line of departure. 727. Plane of direction. — ^The vertical plane containing the line of direction. 728. Plane of sight. — ^The vertical plane containing the line of sight. 729. Plane of splash. — ^The vertical plane containing the chord of the trajectory. 730. Point of fall. — The point at which the trajectory again pierces the horizontal plane through the muzzle of the gun. (See fig. 15, par. 790.) 731. Point of impact. — ^The point at which the projectile first strikes. When the projectile strikes the water before striking any object, the point of impact and the point of splash are the same. (See fig. 15, par. 790.) 732. Point of splash. — ^The point at which the trajectory pierces the surface of the water. (See fig. 15, par. 790.) 733. Pointing. — ^The operation of giving the d.irection and eleva- tion necessary to hit the target. When the sight is used it is called ■' aiming "; when the sight is not used it is called " laying. " There are three cases of pointing: Case I. When direction and elevation are both given by the sight. Case II. When direction is given by the sight and elevation by the range scale on the carriage or by quadrant. Case Hi. When direction is given by the azimuth scale and elevation by quadrant or by the range scale on the carriage. 784. Position finder. — ^An instrument for locating a target. 188 DEFINITIONS. 735. Position finding system. — The term applied to the system used in determining the range and direction to any target &om a battery or station. 736. Powder chamber. — ^The portion of the bore for the recep- tion of the powder charge. It is between the breech recess and the centering slope. 737. Predicted point. — The point at which it is estimated a target will arrive at the end of an assumed interval of time reckoned from the time of the last observation on which the estimate is based. This interval of time is called the "predicting interval." 738. Predioter. — An accessory of the plotting board used to locate the positions of the predicted and the set-forward points on the plotting board. 739. Pressure gauge. — A gauge placed in cannon to measure the maximum pressure developed during firing. 740. Primer. — The device used for igniting the propelling charge. Primers may be friction, percussion, electric, or comtiination (elec- tric and friction). 741. Priming charge or igniter. — Small charges of black powder in the ends of powder sections necessary for the ignition of smoke- less powder. 742. Projectile. — The term applied to a missile thrown from a fiiearm by an explosive. The principal parts of an armor-piercing projectile are the balhstic cap, the armor-piercing cap, the nose or point, the ogive, the bourrelet, the body, the rotating band, the cavity, the base, the base plug, and the fuse plug, as shown in the accompanying diagram. NOSE op BALLISTIC CAP SAS£ PLUG ARMOR /VSIfO\a CAP Fig. 14. The ballistic cap is for the purpose of reducing the effect of or the retardation due to the resistance of the air. It consists of a hollow metal cap placed over the armor-piercing cap. The armor-piercing cap is a piece of soft steel placed over the point to prevent the point from bending or breaking on impact against hard-faced armor, and to thereby increase penetration. The lower part of the ogive is turned off to make a cylindrical bearing surface for the front part of the projectile. This surface, called the boun'elet, has a diameter slightly less than the caliber of the gun, but greater than that of the cylindrical portion of the projectile. DEFINITIONS. 189 The rotating band is forced through the r iflin g of the bore and gives rotation to the projectile. The rotating band also seals the gi'ooves and prevents the escape of gas. When the rifling is worn, due to erosion, broader bands are necessary. Rotation is given to the projectile in order to prevent the projectile from tumbling end over end in the air. The rotation in oui service is clockwise, as viewed from the base of the projectile. The base and fuse plugs are arranged to screw to the left, so that the rotation of the projectile to the right may have no tendency to unscrew them. Coast artillery projectiles are cast iron or steel. The service pro- jectiles are the armor-piercing shot, the armor-piercing shell, and the shrapnel. The shot has a thicker wall and conta'ms a smaller bursting charge than the shell. For the uses of shot and shell, see paiagraph 6. The shrapnel is a projectile which carries a number of bmlets to a distance from, the gun and there discharges them over an extended area. 743. Bacei. — That part of a gun or mortar carriage which rests upon the traversing rollers. On gun carriages the chassis is bolted to the racer, and on mortar carriages the side frames are bolted to the racer. 744. Bamp. — ^An inclined plane serving as a means of travel from one level to another. 745. Bange. — In a limited sense, the horizontal distance from the gun to the target. In a general sense, it is applied to horizontal distances between position finder and target, position finder and splash, gim. and splash, etc. The range of a shot is the horizontal distance from the muzzle of the gun in the firing position to the point of splash. (Practically the range is reckoned from the axis of the gun trunnions in the firing position, instead of from the muzzle, but the difference in range is neglible.) The range used in ballistics is the horizontal distance from the muzzle of the gun in the firing position to the point of fall. (See fig. 15, par. 790.) 746. Bange-azimuth. table. — A table of ranges and the corre- sponding azimuths from a gun to points in the center of the main ship channel or channels. It is kept at the gun and used for fimng without the use of range-finding apparatus. 747. Bange rake. — An instrument used for determining shorts and overs. The camera record is used whenever practicable in preference to the range rake record. 748. Bange table. — ^A table of the elements of the trajectory of a particular camion for a standard muzzle velocity and a given pro- jectile. For direct fire guns, with the range as argument, are tabulated angle of departure; change in elevation for 10 yards in range; time of flight; angle of fall; slope of fall; maximum ordinate; striking velocity; perforation of Krupp armor at normal, and 30° from nor- mal, impact; drift; and deflection for 10 miles per hour wind com- ponent. The ballistic coefficient used in calculating the table is shown. For indirect fire cannon, with elevations and zones as arguments, are tabulated range; time of flight; drift; angle of fall; maximum ordinate; striking velocity; and perforation of deck steel. 749. Bapid-fire gun. — ^A stngle-barrel breech-loading gun pro- vided with breech mechanism, mounting, and facilities for loadmg, 190 DEFINITIONS. aiming, and firing with great rapidity. The breech mechanism is operated by a single motion of the handle or lever. The smaller calibers use fixed ammunition. 750. Bated men. — Enlisted men who have passed examinations for the positions and who have been rated by the coast defense commander as gun commanders, gun pointers, observers, plotters, casemate electricians, chief planters, and chief loaders. (See Appendix A.) 761. Kear slope. — The slope in rear to the battery parade. 762. Receiving table. — The hoist table on which projectiles are placed preparatory to raising. 753. Recoil. — The backward movement of the gun on firing. Counter recoil is the return of the gun in battery. 754. Recoil cylinders. — Hydraulic cylinders for controlling the recoil. 765. Recoil buffers. — Devices on gun carriages for the purpose of reducing the shock due to abnormally excessive recoil. 766. Reference numbers. — The numbers of the graduations of some scales of computing and correcting instruments employed in gunnery, their object being to avoid the liability to error that arises from the use of ' ' right ' ' and ' ' left ' ' in deflection corrections, and of "plus" and "minus" in range corrections. 767. Relocatiou of a target. — A process whereby the range and azimuth of a target from a point may be obtained without observa- tion when the range and azimuth of the target is known from some other point. 758. Rifling. — Helical grooves cut in the surface of the bore for the purpose of giving a rotary motion to the projectile. The rib of metal between two adjacent grooves is called a "land." (See Twist of rifling.) 759. Rimbases. — The masses of metal uniting the trunnions of a cannon with the trunnion band. 760. Bound. — The firing of a single load from each gun of a bat- tery not simultaneously. 761. Salvo. — The simultaneous firing of a single load from each gun or mortar of a battery or from each mortar of a pit. The former is called a "battery salvo " and the latter a "pit salvo." 762. Salvo point. — A selected point on which a salvo from one or more batteries may be centered, the range and azimuth having been carefully determined. 763. Salvo table. — A table giving ranges and azimuths of salvo points. 764. Serving table. — A table for keeping a supply of projectiles (for the intermediate or minor armament) convenient to the breech during firing. 766. Set-forward point. — A point on the com-se of a target in advance of the plotted point at which it is estimated that a target will arrive, at the end of the predicting interval plus the time of flight for the range. It is located (on the plotting board) by laying off from the last plotted position of the target, along the estimated course of the target, a distance equal to the travel of the target during the predicting interval plus the time of flight. 766. Shell. — A projectile with a large cavity for explosive. DEFINITIONS. 191 767. Shell filler. — An explosive used i;o make up the bursting charge in a projectile. 768. Shell loom or shot room. — A room for the storage of pro- jectiles. 769. Shell tracer. — A device attached to the base of a projectile which enables its flight to be followed. In the daytime a smoke (which is visible) is emitted and at night a bright flame. 770. Shot. — A projectile with a small cavity for explosive; also the firing of a single load from a single gun or mortar. 771. Shot gallery. — ^A gallery for the storage of projectiles. 772. Shot hoist. — A device for raising projectiles from the hoist room to the loading or truck platform. Sometimes called ammu- nition hoist. 773. Shot hoist well. — ^The shaft through which the projectile hoist operates. 774. Shot tongs. — A device used in lifting projectiles. 775. Sight. — A device by which the gun pointer gives the gun the proper direction for firing. Sights are of two classes, open and telescopic. 776. Sight standard. — The upright on the carriage which sup- ports the sight. 777. Splash, angle of. — See Danger angle. 778. Splash, point of. — See Point of splash. 779. Striking velocity. — ^The velocity of the projectile at the point of impact. 780. SubcaUber platform. — A platform attached to a disappearing gun carriage for the support of the breech detail during subcaliber practice. 781. Subcaliber tube. — A small gun which is fitted in the bore of a gun of larger caliber. 782. Superior slope. — The top slope of a parapet or traverse. 783. Swell of the muzzle. — The enlargement of the exterior of a cannon at the muzzle. 784. Targ. — ^The piece of metal (or other material) used to indi- cate the intersection of the arms on the plotting board. 785. Throttling bar. — A bar in the recoil cylinder to regulate the size of the orifice through which the oil escapes from one side of the piston head to the other. 786. Throttling pipe. — A pipe connecting the rear ends of two recoil cylinders. The throttling and the equalizing pipes are joined by a connecting pipe through which oil flows from one end of the cylinders to the other without passing through the piston heads. The amount of oil which passes through the connecting pipe is controlled by the throttling valve. The recoil of the gun can be controlled to a certain extent by varying the setting of the throttling valve. 787. Time interval bell or T. I. beU. — A bell to indicate the observing interval. Bells ring simultaneously at the emplace- ments and the observing stations. They are operated by a clock or a motor. 788. Time interval recorder. — The ordinary stop watch. 789. Top carriage. — The top carriage is a part of the gun carriages or guns of 8-inch or greater caliber and for 6-inch guns mounted on 192 DEFINITIONS. DEFUriTIOHS. 193 disappearing carriages. It consistB of the recoil cylinders, the axle bed side frames, and the connecting pipes and transoms. 790. Trajectory. — The curve described by the center of gravity of the projectile in passing from the muzzle of the gun to the point of impact. The lateral travel of the projectile is not proportional to the range, and the trajectory is, therefore, in general, a curve of double curvature, convex to the plane of departure. The trajectory of the range tables ignores the deflecting forces, and lies in the plane of departure. Deflections due to wind and drift are considered separately. There is no appreciable error introduced by considering the trajectory as a plane curve lying in a vertical plane. The "principle" of the rigidity of the trajectory assumes that the figure whose outline is composed of the trajectory and its chord, behaves as if it were cut out of cardboard and rotated up and down with the muzzle of the gun as a center. For example, in fig. 15, accoi-ding to this principle, it is assumed that the shape of the trajectory is the same as if the point S were in the horizontal plane through the muzzle of the gun, and the angle ESO is equal to the angle of fall for a horizontal range equivalent to OS. QS = Kange of shot. tW -Target. FOS —Angle of depfcBsion. ESQ = Angle of aplash— danger angle. HOS = Angle of departure. HOF = Quadrant angle of departure. AFO = Angle of fall (range table) for horizontal range OF. BIT = Angle of imjract. BIG = Angle of Incidence. 791. Travel of projeotile. — The distance from the base of the pro- jectile in its seat to the face of the muzzle of the cannon. 792. Traverse. — The structuie protecting the armament and personnel from flank fire. ., , ,i c ^i. 793. Traverse slope or waU.— The side slope or wall of the 794. Traversing circle. — The metal which is bolted to the con- crete "and which supports the rear part of the carriage in the front pintle type. Traversing wheels roll on this circle. 795 Traversing rollers.— Rollers which rest upon the base ring and which enable the gun or mortar carriage to be given motion 796 Tripping.— The act of releasing the counterweights of a dis- appearing carriage, and thus causing the piece to go into its firing 797 Truck platform.— If the ammunition trucks run on a differ- ent surface from that of the loading platform, this surface is called the "truck platform." ,. , • c e 798 Truimions —The cylmders which rest m bearmg surfaces of the carriage called "trunnion beds." Their axis is perpendicular to the axis of tbe bore and ordinarily in the same plajie; they con- nect the cannon with the carriage and transmit the force of recoil 104227°— 17 13 OPS = Trajectory. F — Point of fall. I = Point of Impact. s —Point of splash. w —Center of target; LV -Height of site. OH = Line of departure. OW = Line of direction. AF -Line of fall. BI — Line of impact. OS -Chord of the trajectory. 194 DEFINITIONS. from one to the other. The faces of the trunnions are the end planes perpendicular to their axis. 799. Trunnion band. — The hoop of which the trunnions of a cannon form a part. 800. Tube. — The inner cylinder of a cannon. 801. Twist of rifling. — The inclination of the grooves to the axis of the gun at any point. When this inclination is constant the twist is uniform; when it increases from the breech to a point near the muzzle it is increasing. Twist is generally expressed in turns per caliber, e. g., one turn in 50 calibers, meaning that the projec- tile makes one complete rotation in passing over a distance equal to 50 calibers, provided the twist were uniform. In most of the major caliber guns in our service, the twist increases from one turn in 50 calibers to one turn in 25 calibers at a short distance from the muzzle and beyond that point it is unifoiin. 803. Velocity. — As used in coast artillery practice, velocity is the rate of travel of a projectile in feet per second. The velocity at the muzzle is the "initial" or "muzzle" velocity. The velocity at the point of impact is the "striking" velocity. The velocity at any point of the trajectory between the muzzle and the point of impact is the ' ' remaining " velocity at that point. 803. Vent. — ^A small cnannel leading from the exterior of the cannon to the powder chamber for the ignition of the powder charge. It is an " axial vent " when it is in line with the axis of the bore. It isa "radial vent" whenitisatrightangles totheaxisof the bore. 804. Zone. — In mortar firing, the area in which projectiles fall for a given charge of powder, when the elevation is varied between the minimum and maximum. It is also used with reference to other divisions of the defensive area, as "outer defense zone," "inner defense zone," etc. See also Zone, 50 per cent. 806. Zone, 50 per cent (sometimes called probable zone). — The space bounded by two parallel lines Avithin which 50 per cent of the points of impact of all shots fired with the same elevation and azi- muth settings will probably lie . The width of the 50 per cent zone in any direction is equal to twice the probable error m that direc- tion. The area common to the 50 per cent lateral zone and the 50 per cent longitudinal zone is the 25 per cent rectangle. Appendix A. EXAMINATION FOB GUNNERS AND FOB SPECIAL BATINGS. EXAMINATION FOR GTrtrKEES. 806. Boards of examination will be convened annually in each coast defense command by the coast defense commander, to meet, if practicable, just prior to, or just after tie close of the indoor instruction period. Separate boards may be convened for the examination of candidates for first and for second class gunners, and separate boards may be convened for the different forts in a coast defense command. Each board will consist of three Coast Artillery officers. When a member of the board is a company com- mander he will be relieved by another officer during the examina- tion of candidates from his company. 807. For purposes of instruction and examination, enlisted men of the Coast Artillery Corps not belonging to companies or batteries upon application will be attached to convenient organizations, and upon qualification will be classified as gunners. Enlisted men of the Coast Artillery Corps on duty outside of a coast defense command may be examined by one or more Coast Artillery officere with whom they are serving or by Coast Artillery officers designated by the department commander, and, if found qualified, will be announced as gunners by the department com- mander. When a mine planter or cable ship is assigned to a coast defense command, the Coast Artillery enlisted men assigned to the vessel may be examined by the officers on duty with the vessel, and, if found qualified, will be announced as gunners by the coast defense commander. (C. C. A. D. R. No. 5.) 808. A candidate to be eligible for qualification as first-class gunner must have qualified previously as second-class gunner, though both qualifications may be made at the same examination. 809. The examination of gunner candidates will be held, as far as practicable, at such places as the material pertaining to the sub- ject in hand is located, and will be made as practical as possible. In determining the qualifications of candidates, credit will be given for practical knowledge of subjects, rather than for text-book answers to questions. 810. The qualifying mark for classification as first or second class gunner will be in each case not less than an average of 75 per cent. Whenever, during the progress of the examination of a candidate for either grade, the sum of the marks received on subjects for which he has already been examined, increased by the maximum allowed for the remaining subjects, is less than 75, he will be dis- 195 196 EXAMINATION FOK GUNNERS. qualified and his examiaation will be discontinued. Whenever, during the progress of the examination of a candidate for either grade, the sum of the marks received on the subjects in which he has already been examined is 75 or more, he will be qualified with- out any further examination. 811. The board will keep a record of itsmarks duringthe exam- ination, but these marks will not be published in orders. The report of the board on each company will be sent as soon as prac- ticable after the completion of the examination to the coast defense commander, who will publish an order announcing the names of those who have qualified as first and second class gunners, and the date of qualification (the date of the completion of the company examination being taken as the date of qualification). EXAMINATION FOR GUNNERS. 197 812. The scope of the examinations for the first and second clase gunners and the relative weights to be given the subjects will be as follows: For candidates in companies assigned to gun defense: For second-class gunners: (a) Service of the piece (practical). This will include an actual drill at the battery in which the candidate will in turn perform the duties of various numbered cannoneers, the range setter, the chief of breech, the elevation setter (mortars only), and the azimuth setter (mortars only) or as many of those duties as the board may direct . . 40 (b) Nomenclature of the various parts of the gun and carriage 5 (c) Action, adjustment, and care of the various parts of guns and car- riages 20 (i) Powders, projectiles, primers, and fuses 15 ) Cordage, gins, shears, and jacks 10 ) United States magazme rifle 15 100 For first-class gunners: (a) The azmiuth instrument (theoretical, 5; practical, 10) 15 (6) Duties in the plotting room (theoretical, 20; practical, 30). The can- didate will act in turn as Nos. 1, 2, 3, 4, and 5 while tracking a moving target (if practicable), or ra as many of those positions as the board may direct 50 (c) Aiming and laying guns or mortars, practical 15 (d) Time-range board (guns) and time-azimuth board (mortars), prac- tical 10 (c) Definitions, C. A. D. E 5 (/) "War ships, characteristic features 5 100 The examination of candidates for first-class gunners of organiza- tions assigned exclusively to rapid-fire guns not provided with separate position finding system will include the following head in lieu of those given under (5) and (d): (fi) ((J) Subcaliber firing 60 The examination in subjects (a), (6), (c), and (d) for both second- class and first-class gunners will be confined to the matdriel of that part of the defense to which the company is assigned. If no azi- muth instrument is included in the battery equipment, the instru- ment used in the instruction will be used in the examination. For candidates in companies and detachments assigned to mine defense: For second-class gunners: (a) Ammunition, nomenclature, and service of guns to which the can- didate's company is assi^ed 15 (6) Material of and the duties in the loading room (except electrical prin- ciples involved) 30 (c) Material for and duties on the water 30 id) Cordage, gins, shears, and jacks 10 (e) United States magazme rifle 15 100 For first-class gunners: (o) Care and preservation of mine material 15 (6) Handling high explosives 20 (c) Knowledge and use of the azimuth instrument and plotting board 20 Id) Engines, generators, transformers, storage batteries, and searchlights assigned to the company of which the candidate is a member 20 (e) Operation of casemate apparatus and of telephones 20 (/) Definitions C. A. D. R 5 100 ids EXAMINATION FOR GUNNERS. EXAUINATION' FOR SPECIAL RATINGS. 813. In each company of coast artilleiy, examinations will be held by the company commander under the direction of the fire or mine commander, at such times as the latter may prescribe, for the purpose of determining enlisted men who are qualified for appointment to rated positions. 814. Records will be kept in each company in the form of eligible lists for each rated position to which enlisted men of the company may be appointed. 818. Examination for rated positions will be confined to first- class gunners or enlisted men who have once been classified as first-class gunners. Candidates who pass with an average of 75 per cent any of the examinations prescribed for rated enlisted men will be carried on the qualified list for appointment to the corre- sponding rated position for a period of one year from the date of examination. (C. C. A. D. R. Nos. 1 and 4^ 816. Enlisted men on the qualified list for a rated position will be classified as first-class gunners from the date of qualfication and so announced in coast defense orders, and such classification will be continued for the time they are entitled to remain on such qualified list. When a man's term of qualification for any rated position expires, he may be continued in such rated position or on the corresponding qualified list by passing a new examination for such rated position, and his classification as first-class gunner will be continued without further examination. (C. C. A. D. R. No.l.) 817. The same enlisted man may be carried on several eligible lists provided he passes satisfactorily the prescribed examinations for such rated positions. 818. Prior to the examination for the rated positions of observers, first or second class, or gun pointer, the candidates will be exam- ined by the post surgeon for defective vision, and no candidate will be rated for these positions who has any defect in vision which would impair his efficiency. 819. An enlisted man holding a rated position need not be re- quired to take the examination for that position until the termi- nation of the one-year period from the date of his last classifica- tion as a first-class gunner, unless his qualifications for the position he holds have not been established to the satisfaction of the fire or mine commander concerned or the coast defense commander, in which case he will be required to take the examination for that position for such time as mav be prescribed by the fire or mine commander concerned. In tlie event of his failure to pass satis- factorily the prescribed examination, he will be disrated immedi- ately by the coast defense commander. (C. C. A. D. R. No. 4.) 820. The scope of the examination for each of the rated positions will be as follows: EXAMINATION FOR GUNNERS. 199 GUN COMMANDER AND GUN POINTER. I. Definitions O.A.D.R. II. Gun and carriage. (a) Nomenclature, purpose, and action of several parts. (6) Packing stuflBng boxes and cleaning recoil cylin- ders. (c) Adjustment of — Quadrant elevation device, sight standard, throttling valve, gas check pad, elevating gear, grease cups, and firing mechanism. (d) Care and preservation, including care of hand counterweights, oiling, and painting. III. Powders, projectiles, fuses, and primers. (a) Blending powder and preparation of powder charges. (5) Pilling and fusing projectiles, (c) Painting projectiles. IV. Preparations for service or subcaUber practice. V. Service of the piece. (o) Duties of each member of the gun section under all conditions. VI. Precautions for safety at the battery. VII. Pointing. (a) Methods of pointing and pointing tests. (6) The telescopic sight (the quadrant for mortars), (c) Emergency system and salvo points. ((f) Bore sighting and orientation. VIII. Regulations governing service and subcaliber practice so far as they affect the service at the emplacements. IX. Mounting and dismounting guns and carriages. X. Characteristic features of the several classes of warships, general knowledge of local shipping, of channels lead- ing to the harbor, and of ranges to prominent fixed objects in the field of fire of the battery. I. Definitions C. A. D. R. II. Position finding system. (a) Detailed knowledge of system employed at the battery. (6) Indication and identification of targets. (c) Duties of each member of the range section under all conditions. (d) Emergency system and salvo points. III. Position finding apparatus. (o) A detailed knowledge of adjustments and use of all position finding apparatus used in the plot- ting room. 200 EZAUINATION FOR GUNNERS. IV. Elementary gunnery. (a) Explanation of the several corrections to be ap- plied to the observed range to obtain the cor- rected range. (6) Effect on the flight of the projectile of variations in the density of the air; the direction and ve- locity of the wind. (c) Use of trial shots and application of data obtained from them (problem). V. Preparation of target practice records. OBSERVER (first OR SECOND CLASS). I. Definitians C. A. D. R. II. Position finding system. (a) Detailed description of that in use at the battery. (b) Indication and identification of targets. (c) Emergency system and salvo points. III. Position finding apparatus. (a) A detailed knowledge of adjustment and use of all observing instruments and range finders in use at the battery. (b) Use of the telephone. IV. Characteristic features of the several classes of warships, general knowledge of local shipping, of channels lead- ing to the harbor, and of ranges to prominent fixed ob- jects in the field of fire of the battery. CASEMATE ELECTRICIAN. I. Definitions C. A. D. R. II. Casemate apparatus. (a) Nomenclature. (6) Testing. (c) Circuits. (rf) Maintenance. III. Troubles and remedies, (a) Lamps and bells. (6) Switches. (c) Ammeters and voltmeters. ((/) Telephones, (e) Engines and machines. CHIEF PLANTER. I. Definitions C. A. D. R. II. Mine planting material. (a) Voltmeter test of a mine circuit. (6) Hydraulic jacks. (c) Nomenclature and use of apparatus aboard mine planters used in planting mines. (d) Capacity of falls and winches. (e) Automatic anchor. EXAMINATION FOB, GUNNERS. 201 III. Drill. (a) Duties of noncommissioned officer on distribution box boat. (6) Duties of noncommissioned officer in charge of planting mines from mine planter, (c) Boat drill with yawl boat. IV. Emergencies. V. Cordage. CHIEF LOADER. I. Definitions C. A. D. R. II. Explosives. (a) Storage of explosives. (6) Guncotton. (c) Drying guncotton and guncotton primers. (d) Preparation of guncotton primers from square cakes. («) Dynamite. (/) Nitroglycerine. (g) Evidence of free nitroglycerine in dyriamite. (Ji) Method of decomposing nitroglycerine to render it harmless, (i) Preparation of priming charges. (i) Trotol. III. Fuses. (a) Description. (6) Tests. (c) Storage of fuses. (d) Preparation of fuses for loading plugs. IV. Loading-room duties. (a) Testing transformer and measuring the resistance of its circuits. (6) Assembling and testing a compound plug, (c) Loading a mine and preparing if for delivery to planter. V. Unloading mines. (a) Precautions. (b) Returning charge to storage boxes. (c) Determination of amount of water to add to gun- cotton. COXSWAIN. The scope of the examination for coxswain will be the same as that prescribed for chief planter, except III (6), for which the following is substituted: Theoretical and practical operation of a distribution box boat, involving a knowledge of the navigation "Rules of the Road," aa pubUahed in Artillery Bulletin No. 117 (Serial No. 132.). (C. C. A. D. R. No. 4.) l/l/i i'.l INDEX A. Absolute deviation, definition 647 Absolute error, defiiiition '.'.'.',[ 663 Aiming (for definition see Pointing) !!!!!!!!!!!!!!!!!!!!!! 733 Aiming points for observers and gun pointers... 79 Ammdnition: Definition (fixed and separate-loading) 578 Dummy, loading with 205 Dummy, simulated firing at inspection ' ] " 341 Dummy, 5-lneli gun (barbette carriage) [[ 188 Dummy, 6-ineh gun (barbette carriage) 188 Dummy, 6-inch gun (disappearing carriige) 165 Dummy, 8-inch gun (disappearing carriage) 155 Dummy, 10-inch gun (disappearing carriage) 155 Dummy, 12-inch gun (barbette carriage) 175 Dummy, 12-inch gun (disappearing carriage) 135 Dummy, 12-moh mortar drill 117 Dummy, 14-inoh gun (disappearing carriage) 135 j;ixed 575,676,578 Fixed, mspection 576 Fixed, storage and care 575 Furnished and maintained by 409 Service, cleaning powder chamber when used 238 With Semple tracer 106 Ammunition cases, empty, storage of 493 AMMumnoN detachment: Three-inch gun drill 192 Four-inch gun drill 192 Four and seven-tenths-inch gun drill 192 Five-inch gun drill (barbette carriage) 183 Six-inch gun drill (barbette carriage) 183 Six-inch gun di'ill (disappearing carriage) 160 Eight-inch gun drill (barbette carriage) 180 Eight-inch gun drill (disappearing carriage) 150 Ten-inch gun drill (barbette carriage) 180 Ten-inch gun drill (disappearing carriage) 150 Twelve-inch gun drill (barbette caixiage) 170 Twelve-inch gun drill (disappearing carriage) 130 Twelve-inch mortar drill 112 Fourteen-inch gun drill (disappearing carriage) 130 Ammunition hoists: Care of- 421 Furnishing of spare parts 408 Installation and mamtenance of 408 Ammunition truck, definition 579 Anchors, inspection of 341 Anemometer, description of. 380 Angle, danger (for definition see Danger angle) 640 Angle of departure, definition 581 Angle of depression, definition 582 Angle of fall, definition 583 Angle of impact, definition 584 Angle of incidence, definition 685 Angle of jump, definition 686 Angle of splash, definition 640 Apparatus, fire control and fire direction 380-402 Apron, definition 688 Aeea: Battle, definition 698 Fire, definition 669 Searchlight, designation of. 346 203 204 INDEX. Armament: Paragraph. Fixed, classification of 5 Intermediate, composition of 7 In coast defenses 4 Major, range differences 220 Major, seating projectile at gun batteries 215 Major, composition of 6 Major and mtermediate, fire direction of 74-91 Maiming of for inspection 335 Manning tables for 26 Minor, fire direction of. 92-109 Minor, Tvbat it consists of 8 Movable^ what it consists of 9 Armor-piercm? cap, definition 742 Arm settee: Member of gun battery manning party 76 Member of mine command mannmg party 269 Member of mortar battery manning party ; 87 Aetilleey boats: Inspection of 308, 309 When to leave moorings 311 Artillery engineer. (See Coast Defense Artillery Engineer.) Artillery inspection in ranks 38 Atmosphere slide rule, description of 381 Axial vent, definition 803 Axis of cannon or axis of bore, definition of 589 Axis of trunnions^, definition 590 Azimuth (of apomt), definition 591 Azimuth circles, inspection of subscales of 341 AziMtTTH computer: Duties of 90 Member of mortar battery manning party 87 Azimuth deviation, definition 648 Azimuth difference, definition 592 Azimuth indices , 219 Azimuth instrument, description of 382 Azimuth keeper, member of mortar battery manning party 87 Azimuth keeper (mortar battery) , duties of. 91 Bag, cartridge, definition L 019 Balanced pillar mount, definition 617 Ballistic cap, definition 742 Ballistics, definition 593 Barbette carriages, definition 617 Barometer, description of 383 Bar, throttling, definition 785 Base une: Definition 594 Symbol for 673 Use of 74 Base plug of projectile, definition 742 Base ring, definition 595 Battery: Assignment of company to 20 Definition 596 Fire direction of intermediate armament 74-91 Fire direction of major armament 74-91 Fire direction of minor armament 02-100 In and out of commission 405 In and out of service 405 Material for preservation of 408 Battery command: Chapter on 43-73 Composition of 13 Definition of 13 Drill, modification of, not authorized 46 Drill under emergency conditions 56 INDEX. 205 Batteey command— Continuod. Parasrapli Duties of battery commander 4^56 Duties of emplacement officer .--!..-!"!!!!"."!!!]. 65-68 Duties of gun and pit commander 69-71 Duties of gun pointer .."[[[[" 72 Duties of mecnanic 73 Duties of range officer ...[[ 57-60 Emergency conditions .'.' 54-55 Equipment, implements, and reserve ammunition for ....] 45 FireH3ontrol installation, changes in 47 43 Fire direction and fire control for !..!!!!!.]!!!!!!! '52 Improvement ia driU. or devices 49 Inspection by fort commander """"][][[[ 51 Location of battery commander 53 Manning table for ].. ..".[]]]]]]] 26 Observers of , 61-63 Plotter, responsibility of ",!!!!!!! 64 Responsibility of battery commander 44 Subcaliber practice of, in emergency condition 56 Symbols for stations 673 Training of detaib for fire, mine, and fort commanders' stations 50 Training of range sections and telephone operators 50 Battery commander: Duties after firing piece S9 Duties of, at 12-iQcn mortar drill 116 Duties of, in connection with firing minor armament 100 Duties of, in general 43-56 How to assign officers 35 Indicating targets 77 Location of 53 Member of gun battery manning party 76 Member of mortar battery manning party 87 Responsibility for property 406 Responsibility of 44 Traming of gun commander and gun pointers 204 Battery commander, assistant, member of mortar battery manning party. 87 Battery commander's observer, member of mortar battery manning party 87 Battery commander's station: Manning party for 93 Manning party for (gun battery) 76 Manning i)arty for (mortar battery) 87 Battery for firing, furnished and maintained by 409 Battery p£M"ade, definition ^ 597 Battery salvo, definition .- 761 Battle area, definition 598 Battle chart, definition 599 Bell, time interval (T. I.), definition 787 Benchffi, circulatj supplied by 408 Bench tools, furnished by 409 Black powder, storage of. 490 Blending, definition, 600 Board of examination: For gunners, how organized 806 For gunners, keeping of records 811 boats: Artillery, inspection of 308, 309 Artillery, when to leave moorings = 311 Distribution box, assignment of. 310 Inspection of 341 Manning table for 26 Book: Emplacement, definition 657 Emplacement, inspection of 341 Fort record, definition 679 BoRfi: Definition -■ 601 How cleaned after firing ■--. ^ - 239 Boresirfiting 218-220 ^tiurrBlet, definititm 742 20G INDEX. Bheech: Paragraph- Definition 602 Closing model 1888, 12-inch gun (barbette carriage) 179 Closing model 1888, 12-inch gun (disappearing carriage) 139 Closing model 1888, 14-inch gmi (disappearing carriage) 139 Closing model 1895, 12-inch gun (disappeariag carriage) 141 Closing model 1895, 14-inch gun (disappearing carriage) 141 Face of, definition 605 Opening model 1888, 12-inch gun (barbette carriage) 178 Opening model 1888, 12-inch gun (disappearing carriage) 13S Opening model 1888, 14-inch gun (disappearing carriage) 138 Opening model 1895, 12-inch gun (disappearing carriage) 140 Opening model 1895, 14-inch gun (disappearing carriage) 140 To open and close on 12-inch gun (barbette carriage) 177 Beeechblock: Definition 603 Dismantling of 453 How cleaned after firing 239 Breech bushing, definition 604 Breech mechanism: Definition 606 Examination of 458 Breech recess, definition ^ 607 Breech reinforce, definition 608 Buffers, counter-recoil^ definition 637 Buffers, recoil, definition 755 Bugles used in signaling 214 Buudings, inspection of general condition 341 Built-up cannon, definition 610 Bursting charge, definition 626 C. Cable: Inspection of storage of 341 Submarine mine, when tested 326 Testing records, examination of 341 Caliber, definition 609 Cameras, and supplies, furnished and maintained by 409 Cannon: Axis of, definition 589 Built up 610 Classification of 610 Definition 610 Wire wound, definiticn 610 Cannoneer, definition 611 Cap, armor-piercing, definition 742 Cap, ballistic, definition 742 Cap-square, definition 613 Capital, definition '. 612 Caretaker detachments, regulations for 470-477 Caeriages: Balanced pillar^ definition 617 Barbette, definition 617 Care of 443-452 Casemate, definition 617 Definition 614 Disappearing, description 617 Fixed, deflmtion 615 Furnished and maintained by 409 Masking parapet mount, definition 617 Movable (wheeled mounts), definition 616 Painting of 426 Seacoast, definition 617 Caeteidoe: Definition 618 Use of, for fixed ammunition 198-202 Cartridge bags, definition 619 Cartridge case, deflmtion 620 Case I: Definition of. 733 Use of 80,223 INDEX. S07 Case 111 Pftfagfaph. Deflnition ot , , , , 733 Use of 80,223 Case III; Definition of. ,...,..,..,.... , 733 trseef. , ,..,.,..-. BO, 223 Case, cartridge, definition i ...;. ^ .;..... ^ : C20 Cases, metallic, care of ....,...,...,.. iefl Casemate carriages, definition .....:..... Cl7 Casemate electrician, scope of examination for B20 Centering slope, definition 623 Center of impact, definition 623 Center ot target, definition G21 Center, pintle, definition. 025 Central heating plant, under control ot 318 Chamber, powder, definition 736 Charge, definition 026 Charge (or powder) section, defmition C27 Cliart, battle, definition 599 Chart, difference, definition 649 Chart, harbor, definition 688 Chase, definition 028 Chassis, definition 029 Chief loader, scope of examination for S20 Chief planter, scope of examination for 820 Chord of the trajectory, definition 030 Circle, traversing 794 Circular benches, supplied by 408 Clinometer, defiiiition 031 Clinometer rest, definition 632 Coast Artillery command, units of the tactical chain 12 Coast Artillery company. (See Company, Coast Artillery Corps.) Coast Artillery compames, assignment of 20 Coast Artillery Corps company, size of 19 Coast Artillery inspection. (See Inspection.) Coast Artillery materiel, responsibility for 403 Coast Artillery militia, definition 633 Coast Aetilleey suppokts: Definition 634 Use of 2 Coast Artillery troops, use of 2 Coast defense adjutant, duties of. 313 Coast defense armament 4 Coast defense aetilleey engineee 314-326 Appointment of 314 Assistance to ordnance ollicer 321 Control of enlisted specialists 322, 323 Estimates, submitted by 319 Inspection of property 314 Operation of nre control communications 318 Operating of heating plants 318 Operation of ice ana pumping plants 318 Operating of lighting plants 318 Operation of power plants and power distribution 318 Operation of searchlights 318 Property accountability 314 Reports on internal combustion engines 320 Request to ordnance officer for assistance 325 Eequisitions, submitted by 315 Returns, rendered by 315 Stores, issued by 316, Test of submarine mine cable 326. Transfer of property from one fort to another SIT' Coaste defense command: Chapter on 29&-334 By whom designated 299' Composition of. 12, 18, 298 Controlofcommand with reference to drill and supplies 305 6oAST defense commander: Assignment of 31 Control of boats , , -.,,^,, 507/ 208 INDEX. Coast defense commander— Continued. Paragraph. Control of command in action 303 Control of searchlights 345, 347, 348, 352 Designated as tactical and administa-ative officer 300 Detailing assistants to artillery engineer 324 Division of water area 302 Duties when vessels of war arrive in harbor 312 How to have repairs made 306 Inspection of boats 308 Inspection of ungarrisoned forts 477 Preparation of general and special situation 292 Requirements for his officers 304 Station (tactical) 301 To accompany inspectors of staff corps and departments 334 Transfer of Engineer and Signal Corps and mine property 31 7 Transfer of ordnance materiel 329 Coast defense headquarters: Manning table for 20 "War Department designation 299 Coast defense ordnance officer: Accountability for property 327 Assistance fi'om artillery engineer 331 Duties of 327-331 In charge of ordnance repair shop 330 Inspection of property 327 Issue of property 329 Returns rendered 328 Requisition for stores 328 Supervision of ordnance machinists : 330 Coast defense quartermaster: Duties of 332, 333 Inspection of boats , 332 Responsibility for boats 332 Use of ordnance repair shop 333 Coast ^uard, use of 2 Coast line, defense of by naval and land forces 1 Coincidence range finding system: Definition 74 For gim battery 84, 85 For mortar battery 92 Commands: Following of 267 Given by fire commander 264, 268 Given by fort commander 291 How given by gun commanders and gun pointers 204 Indication and identification of target 78 Samples given by fire commander 265 Commercial detonators 495-500 Inspection 500 Package 495 Storage and care 496-499 Communication, means of. 365-379 Communication lines, underground, installed by 408 Communication officer: Duties of 257, 258 Member of fne command manning party 249 Company: Assignment to battery and mine command 20 Coast Artillery Corps, size of 19 Formations and marching maneuvers 37-42 How to form 37 To march to battery or station 39 Company commander, duties with reference to manning bodies 28 Controllers, inspection of 341 Corridor, definition 635 Corridor wall, definition 636 Counter-recoil buffers, definition , 637 Counterweight, definition > — .-....;. - 638 Counterweight well, definition '^ ...-.-....-. ■ -eis Crest, exterior, definition .....,--- 1 ..---■ .- 666 INDEX. 209 _. . . , Paragrapli. Crest, interior, definition 694 Crow's nest, definition ...\."" 639 Curved fire, definition 676 Cylinders: Recoil, cleaning of 452 Kecoil, definition ] ] 754 r>. Daily attendmice record 43 Danger angle, definition 640 Danger range, definition 641 Danger space, definition ] 641 Data, transmitting to pits 87 Data line, definition 642 Datum point, definition 643 Defective powder, reporting on 234 Defense of coast Ime 1 Defense, mine, comjwsition of 10 Defenses, iMidward, definition 699 Definitions 577-805 Deflection, definition 644 Deflection boards: De-scription of, for guns of the intermediate armament...". 384 Description of, for guns of the major armament 384 Description of, for guns of the minor armament 386 Description of, for mortars 385 For minor armament 109 Deflection board operator: Duties of, as member of gun battery 80 Member of gun battery manning party 76 Member of manning piarty 93 Deflection recorder's board: Description of 387 Material for construction of 408 Delivery table, definition 645 Density of loading, definition 646 Departure, angle of, definition 582 Departure, line of , definition 700 Departure, plane of. definition 726 Depression, angle 01, definition 581 Depression position finder: Description of 388 Lewis, model 1907, adjustment of 390 Swasey, adjustment of 389 Detachment, caretaker, regulations for 470-477 Detonators, commercial 495-500 bispection 500 Package 495 Storage and care 496-^99 Deviation, definition 647 Deviation, azimuth, definition 648 Devices, submission of improvements 49 Difference chart, definition 649 Direct fire, definition 676 Directing gun, definition 650 Directing point, definition 650 Direction, line of, definition 701 Direction, plane of, definition 727 Disappearing carriages, definition 617 Disappearing guns, traming of gun pointer to get on target 226 Dispatch boats, by whom supervised 307 Distribution box boats, assignment of 310 Distribution boxes, inspection of 341 Doors, inspection of condition of 341 Drains, inspection of condition of 341 Drawing boards* furnished and maintained by 409 Drawing instruments furnished and maintained by 409 Drift, definition 661 104227°— 17 14 210 INDEX. Drill, 3-inch gun: Paragraph. Composition of ammunition detacliment 192 Composition of gun detachment 191 Composition of gun section 190 Composition of reserve detachment 193 Detail di-ill 197 Method of firing 196 Notes on drill 198-202 To call off 195 To post gun section 194 Drill, 4-inch gxtn: Composition of ammunition detachment 192 Composition of gun detachment 191 Composition of gun section 190 Composition of reserve detachment 193 Detail drill 197 Method of firing 196 Notes on drill 198-202 To call off 195 To post gun section 194 Drill, 4,7-inch gun: Composition of ammunition detachment 192 Composition of gun detachment 191 Composition of gun section 190 Composition of reserve detachment 193 Detail diill 197 Method of firing 196 Notes on drill 198-202 To call off 195 To post gun section 194 Drill, 5-inch gun (barbette carria-je): Composition of ammunition detachment 183 Composition of gun detachment 182 Composition of gun section 181 Composition of reserve detachment 184 Detail drill 189 To call off 186 To load and fire 187 To post gun section 185 Use of dummy ammunition 188 Drill, 6-inch gun (barbette carrlage): Composition of ammunition detachment 183 Composition of gun detachment 182 Composition of gun section 181 Composition of reserve detachment 184 Detal drill 189 To call off 186 To load and fire 187 To post gun section 185 Use of dummy ammunition 188 Drill, 6-inch (disappearing carriage): Composition of ammunition detachment 160 Composition of gun detachment 159 Composition of gun section 158 Composition of reserve detachment 161 Detail drill 166 Notes on drill 167 To call off 163 To load and fire ; 164 To post gun section 162 Use of dummy ammunition 165 Drill, 8-inch gun (barbette carnage) 180 Drill, 8-inch (disappearing carriage): Composition of ammunition detachment 150 Composition of gun detachment 149 Composition of gun section 148 Composition of reserve detachment 151 Detail drUl 156 Notes on drill 167 To call off 153 To load and fire 154 INDEX. 211 Deill, 8-inch (disappearing cakkiage)— Continued. Paragraph. To post gun section 152 Use of dummy ammunition 155 Drill, 10-inch gun (barbette carriage) 180 Drill, 10-inch gun (disappearing carriage): Composition of ammunition detachment 150 Composition of gun detachment 149 Composition of gun section 148 Composition of reserve detachment 151 Detail drill 156 Notes on drill 157 To call off '.'. 153 To load and fire 154 To post gun section 152 Use of dummy ammunition 155 Drill, 12-inch gun (barbette carruge): Composition of ammunition detachment 170 Composition of gun detachment 169 Composition of gun section 168 Composition of reserve detachment 171 Detail drill 176 Notes on drill 177-179 To call off 173 To load and fire 174 To post gun section 172 Use of dummy ammunition 175 Drill, 12-INCH gun (disappearing carriage): Adjustment of shot trucks 143 Composition of ammunition detachment 130 Composition of gim detachment 129 Composition of gun section 128 Composition of reserve detachment 131 Detail diill 136 Forcing gun into battery 144 Notes on drill 137-147 To call off 133 To load and fire 134 To post gun section 132 Use of dummy ammunition 135 Use of lanyard 142 Drill, 12-inch mortar: Composition of ammunition detachment 112 Composition of mortar detachment Ill Composition of pit section 110 Composition of reserve detachment 113 Detail drill 120 Notes on drill 121-127 To call off 115 To load and fire 116 To post pit section _. 114 Use of dummy ammunition '. 117 Drill, 14-inch gun (disappearing carriage): Adjustment of shot trucks 143 Composition of ammunition detachment 130 Composition of gun detachment 129 Composition of gun section 128 Composition of reserve detachment 131 Detsul drill 136 Forcing gun into battery 144 Notes on drill 137-147 To call off 133 To lead and fire 134 To post gun section 132 Use of dummy ammunition 135 Use of lanyard 142 Drill: Company formation for 37 Not to be modified by battery commander 46 Primer used at 207 Searchlight, night , , , 342-304 212 INDEX. Deill— Continued. Paragraph. Station of battery commander during 53 Submission of improvements 49 IJnder emergency conditions 50 Dummy ammunition: 5-inch gun (barbette carriage) 1S8 6-inch gun (barbette carriage) 188 G-lnch gim f disappearing carriage) 165 8-inch gun (disappearing carriage) 155 10-inch gun (disappearing carriage) 155 12-inch gun (barbette carriage )_ 175 12-inch gun (disappearing carriage) 135 12-inch mortars 117 14-inch gun (disappearing carriage) 135 In simulated fire 341 Loading with 205 Dummy projectiles, care of 465 Dynamite 501-511 Inspection 508-511 Package 501 Storage and care 502-507 What it can be stored with 507 E. Ears, placing finger tips in when firing forbidden 240 Ears, when to use protectors 240 Electriclights, inspection of condition of, 341 Electric plants, supplies furnished for 411 Electrical equipment, seacoast armament 321 Electrical range transmitter, symbol for 673 Electrical transmission device, where used for communication 365 Electrician, master. (See Master electrician.) Electrician sergeants: By whom supervised 322 Definition 652 Member of fire command manning party 249 Member of fort command manning party 276 On ungarrisoned fort 473 Elevation, definition 654 Elevating band, definition 653 Elevating mechanisms, inspection of. 341 Elevation table, definition 655 Emergency station: Symbol for 673 Telephone operator member of gun battery maiming party 76 Emergency system: Definition 74 Use for gun battery 86 Use for mortar battery 92 Emplacement: Definition 656 General instructions for service at 203-227 Gun battery, by whom commanded 69 Inspection oi condition of 341 Under care of 407 Emplacement book: Definition 657 Examination of 341 Emplacement officer: Duties of 65-68 Duties of at 12-inch mortar drill 118-120 Inspection by 66 Reports 67, 68 Responsibility of 65 Energy of the projectile, definition 658 Engineer: By whom supervised 322 Definition 659 Member of manning party for searchlights 353 Engineer Corps, inspections by officers of 334 INDEX. 213 Engineer Depaktment: Paragraph. Materiel supplied, installed, and maintained by 407, 408 Regulations pertaining to property of 412-421 Enlisted specialists: Definition 660 Employed under 322 How not to be employed , 323 Engine oil 423 Engines^ inspection of 341 Equsillzmg pipe, definition 661 Erosion, denmtion 662 Ebbob: Definition 663 In prediction, wliat it is 227 Probable, definition 664 Estimates submitted by coast defense artillery engineer 319 Examination boards for gimners 806 examination: For casemate electrician 820 For chief loader 820 For chief planter .• 820 For gun commander 820 For gunners 806-812 For gimners and for special ratings 808-820 For gunners, holding of 809 For gmi pointer 820 For observer 820 For plotter 820 For special ratings 813-820 Scope of, for first and second class gimners 812 EzpLosrvEs: Black powder 490 Commercial detonators 495-500 Definition 664 Dynamite 501-511 Explosive D 512-522 Fixed ammunition 575, 576 Fuses and primers 523-528 General instructions 478-494 Guneotton 529-545 Ordnance pamphlets referring to (note following) 494 Projectiles, filled 569-574 Smokeless powder 553-568 Storage and care of 478-575 Trotol 546-552 EXPLOSIVE D 512-522 Inspection at forts 520-522 Package 512,513 Storage and care 514, 519 What it may be stored with 519 Exterior crest, definition 666 Exterior slope, definition 667 F. Fall, angle of, definition 583 Fall, line of, definition 702 Fall, point of, definition 730 Field of fire, definition 668 Field works 3 Fire area, definition 669 FiBE commands: Chapter on 249-275 Composition of 14 Illuminating light of 352 Regulations concerning 249-268 Symbols for stations 673 FiKE commandeb: Assignment of 32>250 Commands given by 260, 264 214 INDEX. FiEE COMMANDER— Continued. Paragraph. Commands to battery commands 264, 268 Control of batteries 263 Control of searchlights 261, 348-350, 352 Description of plotting for 392 Duties of, in action 262 Duties, responsibilities, and how assigned 250-256 In action 262 Indication of target 260 Manning parties, composition of 249 Manning parties, for 249 Order of fire for batteries 263 Requirements for his officers 256 Responsibility of, with respect to drills and tactical efficiency 251 Responsibility of, with respect to equipment and supplies 254 Searchlights imder control of 261 Station of 253 Staff officers of 257 Visits to batteries and companies 255 I'IKB COMMANDER'S STATION: Manning table for * 26 Telephoner to, member of manning party 249 Fire control, definition 670 FntE CONTROL apparatus: Chapter on 380-402 Furnished and maintained by 409, 410 Fire control communication, repaired by 318 Fire control diagram, definition 671 Fire control installation: Definition 672 Permanent changes 48 Provisional, temporary changes 47 Fire control power plants, under care of 407 Fire control stations; Inspection of 341 Supplies furnished for 411 Fire comrol symbols 673 Fire direction: By battery commander 52 Definition 674 For batteries of the intermediate armament 74r-91 For batteries of the major armament 74-91 For batteries of the minor armament 92-109 To improvise method for 55 Fire direction apparatus 380-402 Fire discipline, definition 675 Fire: Holding by jtmior commander 245 Kinds of, definition 676 Fireman: By whom supervised 322 Definition 677 Member of manning party for searchlights 353 Firing attachments, inspection of 341 Firing batteries: Furnished and maintained by 409 Inspection of, and circuits 341 Firing circuits on carriages, installation of wiring 409 Firing leaf, inspection of firing pin 212 Firing mechanism, care of 4G0 First-class gunner: Eligibility for 808 Qualifying mark 810 Scope of examination for 812 Fixed ammunition 575, 576 Definition 578 Inspection 576 Storage and cai'e 575 Fixed armament, classification of 5 Fixed carriage, definition 615 INDEX. 215 Paragraph. js, wliero used for communication 365 Fleet, active 2 Fleet, reserve 2 Floor covering, supplied by 408 Forcing slope, definition 678 Formation, company 37-42 Formation line, simulated at drill 266 FOBT command: Chapter on 276-297 Composition of 12, 17 Definition of 12 E elation of oJficers 30 Symbols for stations 673 What it consists of 277 FoKT commander: Assignment of 31 Assignment of duties to fire commander 262 Commands 291 Control of searchlights 346,347-348,352 Control of water area when more than one fort command covers area 280 Estimating the situation 290 Indication of target 289 In searchlight control drill 364 Inspections by 51 Manning party tor 276 Reports of the fort commander's detail 288 Sequirements for his officers 282 Responsibility to coast defense commander 278 Staff officers for 283 Station of 281 Tactical duties 279 To accompany officers of supply corps and departments in inspection. . . 334 To prescribe limits of batteries, etc 412 Fort commander's detail, reports made by 288 FOKT COMMANDEB'S STATION: Manning party for 276 Manning table for 26 FoETmCATioN light: Equipment, installation and maintenance of 408 Equipment, spare parts lor 408 FOETIFICATION POWER PLANTS: Appliances furnished by Ordnance Department 409 Ui^er care of 407 Fortifications, permanent 3 Fortifications, semipermanent 3 Fort record book, definition 679 Fort switchboard, maiming table for 26 From battery, definition 680 Fuse, definition 681 Fuses and primers 523-528 Disassembling forbidden 527. Inspection 528 Package 523 Storage and care 524-527 Fuse plug of projectile, definition 742 a. Gallery: - Definition 682 Inspection of 341 Shot, definition 771 Gas CHECK pad: Adjustment of 457 Care of 456 Gas check seat: Cleaning during firing 237 Definition 683 Gasoline generating sets, lubricating oil for 408 Gauge, pressure, definition 739 216 INDEX, General instructions: Paragraph. Care of materiel 403-406 Service at ttie emplacements 203-227 Storage and care of explosives 478, 494 General principles, chapter on 1-18 Generators, inspection of 341 Graphite 423 Grease cup: Filling of 444 Inspection of 341 Grooves (rifling), definition 758 Grounds, inspection of 341 Guard, coast, use of 2 Gun batteries: Range differences of, in major armament 220 Seatmg projectile of, in major armament 215 Gun carriage circuits, installed by 409 Gun carriages, motors installed on, by 409 Gun commander: Duties of 69-71 Duties of, with reference to range 400 In charge of emplacement 70 Responsibility of 69 Scope of examination for 820 Trammg of 204 GuK company: Assignment of 21 Sections 22 Guncotton, dry 541-545 GUNCOTTON, WET 529-540 Inspection at forts 540 Inspection by the Ordnance Department 539 Package 529 Storage and care 530-538 What it can be stored with 537 Gun detachment: Three-inch gun drDl 191 Four-inch gun drill 191 Four and seven-tenths-inch gun drill 191 Five-inch gun drill (barbette carriage) 182 Six-inch gun drill (barbette carriage) 182 Six-inch gun drill (disappearing carriage) 159 Eight-inch gun drill (barbette carriage) 180 Eight-inch gun drill (disappearing carriage) 149 Ten-inch gun drill (barbette carriage) 180 Ten-inch gun drill (disappearing carriage) 149 Twelve-inch gun drill (barbette carriage) 169 Twelve-inch gun drill (disappearing carriage) 128-147 Fourteen-inch gun drill (disappearing carriage) 128-147 Gun drill, 3-lnch 190-202 Gun drill, 4-inch 190-202 Gun drill, 4.7-inch 190-202 Gun drill, 5-inch f barbette carriage) 181-189 Gun drill, 6-inch (barbette carriage) 181-189 Gun drill, 6-inch (disappearing carriage) 158-167 Gun drill, 8-inch fbarbeUe carriage) ISO Gun drill, 8-inch (disappearing carriage) 148-157 Gun drill, 10-inch (barbette carriage) 180 Gun drill, 10-inch (disappearing carriage) 148-157 Gun drill, 12-inch (barbette carriage) 168-179 Gun drill, 12-inch (disappearing carriage) 128-147 Gun drill, 14-inch (disappearing carriage) 128-147 Gun levers, definition 685 Gunner: Examination for 806-812 First class, eligibility for 808 First class, qualifying mark 810 First class, scope of examination for 812 Places for noldmg examination 809 Second class, qualifying mark 810 INDEX. 217 GmraEB— Continued. Paragraph. Second class, scope of oxamination for 812 When enlisted men are classified as 807 Gunner, master. (Se« Master gimner.) Gun pointzes: Aiming points for 79 Determination of excellence of work 225 Kethod of pointing 223 Scope of examination for 820 Test, assignment, and responsibility of 72 Training of 204 Training to get on target 226 Gunnery, definition 686 Gun or piece, definition 684 Gun platform, definition 687 Guns: Automatic, definition 709 Care of 434-442 Definition 610 Description of plotting board for 391 Directmg 650 Furnished and maintained by 409 Intermediate armament, description of deflection board for 384 Intermediate armament, description of range board for 394 Major armament, description of deflection board for 384 Major armament, description of range board for 394 Marking of 429 Minor armament, description of deflection board for 386 Minor armament, description of range board for 395 Numbering of 430 Painting of 425 Kapid fire, definition 749 Retracting 6-inch (disappearing carriage) 167 Retracting 12-inch or 14-mch (disappearing carriage) 145-147 Semiautomatic, definition 709 Gun section: Three-inch gun drill 190-196 Four-inch gun drill 190-196 Four and seven-tentlis-inch gun drill 190-196 Five-inch gun drill (barbette carriage) 181-188 Six-inch gun drill (barbette carriage) 181-188 Six-inch gun drill (disappearing carriage) 158-165 E^ht-inch gun drill (barbette carriage) 180 Eight-inch gun drill (disappearing carriage) 148-155 Ten-inch gun drill (barbette carriage) 180 Ten-inch gun drill(disappearing carriage) 148-155 Twelve-inch gun drill (barbette carriage) 168-175 Twelve-inch gun drill (disappearing carriage) 128-135 Fourteen-inch gun drill (disappearing carriage) 128-135 H. Hand tools furnished by 409 Harborchart, definition 688 Harbor vessels, by whom supervised 307 Height of site, definition 689 Heliograplis, whereused for communication 365 High angleflre, definition 676 Hoistroom, definition 690 Hoists, ammunition, care of. 421 HoistSjinspection ofconditlonof 341 Hoists, shot, definition 772 Hoop, definition 691 Horizontal base system: Definition 74 Gun battery 80 Mortar battery 89 Howitzers, definition 610 Hydrolene oil 409, 423 Hygrometers, furnished and maintained by 409 218 INDEX. I. Paragraph. Ice plants , under control of 318 Identification of target: Division of water area in identifying targets 302 Gun battery command 77-79 Mortar battery commander 88 Igniter of priming charge, definition 741 Illuminating circuits on carriages, wiring installed by 409 Illuminating lights, use of 349, 352 Impact, angle of, definition 584 Impact, line of, definition 703 Impact, point of, definition 731 In battery, definition 692 Incidence, angle of, definition 585 In commission defined 405 Indication of target: Coast defense commander, division of water area for 302 Fire commander 2fi0 Fort commander 289 Gun battery commander 77-79 Mortar battery commander 88 Indicator, wind component, description of 401 Infantry, to form as 42 Initialvelocity or muzzle, definition 716 In service, defined 405 Inspection: Artillery boats 308, 309 Artillery in ranks 38 By coast defense ordnance officer 327 By emplacement officer 66 By officers of Engineer Corps 334 By fort commanders 51 By officers of Ordnance Department 334 By ofiicers of Quartermaster Corps 334 By range officer 58 By officersof SignalCorps 334 Company formation for 37 Of coast artillery armament 335-341 Of drains 414 O f explosives 478 f piece after firing 239 Of safety pin on firing leaf 212 Of stations and emplacements 336 Of ungarrisoned forts 447 Preceding firing 230, 241 Reports of range officer after 59 Inspector, duties of, in artillery inspection 335-341 Instructions: General, for care of matMel 403-406 General, forservice at emplacements 203-227 General , for storage and care of explosives 478-494 Posting in magazines 494 Intelligenceline, definition 693 Interior crest, definition 694 Interior slope, definition 695 Interior wall , definition 696 Intermediate armament, composition of 7 Internal combustion engines, reports on 320 J. Jacket, definition 697 Jump. (For definition see Angle of jump.) Junior commander, when to hold fire 245 K. Kerosene 409, 423 Keys of magazines, by whom kept 484 Kinds of fire, definition 676 INDEX. 819 Land force: Paraerapli. Division of 7 3 What it is composed of 2 Lanyaed: How operated 210 When detached 244 Lands (rifling), definition 758 Landward defenses, definition 699 Lateral deviation, definition '.'..'.'. 647 Lateral error, definition ]][[" [[[[[[.[]['.'." \[ 663 Launches, hy whom supervised 307 Laying, definition 733 Levers, gim, definition 686 Lewis depression position finder, model 1907, adjustment of. 390 Lighters, by whom supervised 307 Lighting plant, imder control of 318 Line of departure, definition 700 Line of direction, definition 701 Line of fall, definition [. 702 Line of impact, definition 703 I^ine of sight, definition 704 Load J definition 705 Loadmg, density of, definition 646 Loading platform, definition 706 Loading tray, definition 707 Longitudinal deviation, definition 647 Longitudinal error, definition 663 Lot, definition 708 Lubricating oil for 25 K. W. sets 408 M. Machine guns, definition 709 Magazines: Definition 710 Keys of^ by whom kept 484 Inspection of 341 Hegulations concerning temperatures 489 Ma^etos for firing, furnished and maintained by 409 Major armament, definition 6 Maneuvering ring, definition 711 Maneuvers, inarching 37-42 Manning bodies, training of personnel by company commander 28 Manning paeties: Fire command, duties of 259 Fire commander's primary and secondary stations 249 For fort commander's station 276 For gun battery 76 For minor armament 93 For mortar battery 87 For searchlights 353-356 For stations of minor armament 93 Mine commander's primary and secondary stations 269 Manning table: Details 27 For armament 26 In barracks 29 Marching maneuvers 37-42 Masking parapet mount carriages, definition 617 Masteb electeicun: By whom supervised 322 Definition 712 Member of fort command manning party 276 Master gunnee: By whom supervised 322 Definition '. 713 Matches never in magazines 491 Uatinel, care of 403-477 220 INDEX. Materiel officer: Paragraph.. Control of searchlights T. 350 Fort commaiid, duties of 285-287 Member of fort command maaming party 276 Kesponsibility for searchlights 354 Supervision of enlisted specialists 322 Mean absolute deviation, definition 647 Mean absolute error, definition 663 Mean lateral deviation, definition 647 Mean lateral error, definition 663 Mean longitudinal deviation, definition 647 . Mean longitudinal error, definition 663 Mechanic, assignment and duties of 73 Mechanical range indicators, installation and maintenance of 408 Mechanical range transmitter, symbol for 673 Mechanical transmission device, where used for communication 365 Meteorological observer, duties of 293-296 Meteorological station: Manning table for 26 Regulations for 293-296 Symbol for 673 Mining casemate, symbol for 673 Mine cases: Inspection of painting of 341 Inspection of piling of 341 Mine company, assignment of 20 Mine company, sections of 24 Mine command: Chapter on 24^-275 Composition of 15 Manning parties, composition of 269 Regulations concerning 269-275 Symbols for stations 673 Mine commander: Assignment of 32 Control of batteries 275 Control of searchlights 348-349, 351-352 Designation of mine property officer 274 Duties of, in general 270-275 How to assign ofiicers 34 Maiming parties for 269 Responsibility of, with, respect to di'ills and tactical elBciency 270 Responsibility of, with respect to material and apparatus 273 Station of 272 Mine commander^'s station, manning table for 26 Mine defense, composition of 10 Mine light, whom under control of 351 Mine planters, by whom supervised 307 Minor armament, definition 8 Misfire, regulations governing 242 Mobile troops, organization of 3 Mooring ropes, inspection of 341 Mortar battery: Drill 110-127 Manning details 87 Prediction tests for 227 Mortar company: Assignment of 21 Sections 23 Mortar detachment, 12-inch mortar drill Ill Mortar drill, 12-inch 1 10-127 Mortars: Care of 434-442 Definition 610 Description of deflection board for 385 Description of plotting board for 393 Dismounting of 451 Furnished and maintained by 409 Marking of 429 Methods of testing orientation 221 INDEX. 221 MoETAKs — Continued. Paragraph. Numbering of 431 Orientation of 221-222 Painting of 425 Quadrants, testing adjustment 222 Motors, inspection of 341 Motors, operation on gun carriages 448 Motors on gun carriages, installed by 409 Mount or carriage, deiimtion 614 Movable armament, composition of 9 Movable carriage (wheeled mount), deflnition 616 Moving targets, ranges^ how determined 62 Mushroom head, deflnition 714 Musician: Member of gun battery manningparty 76 Member of mortar battery mannmg party 87 Muzzle, deflnition 715 Muzzle or initial velocity, definition 716 Muzzle, swell of, definition 783 N. Naval forces, composition of 2 Night drills: Battery 361 Coast defense command 362 Fire command 362 Fort command 362 Object 360 Searchlight control drill 364 Searchlights 342-364 Nightfiringfor minor armament 105 Niteogltceein: Danger in exudation 509 Destruction of 609 Test for , 509 Noncommissioned officers, senior, designation of 25 Notes on fire direction of minor armament 103-109 Numbers, reference, definition 756 O. Observation telescopes, furnished and maintained by 409 Obsekvees 61-63 Aiming points for 79 Battery commander's, member of mortar battery manning party 87 Member of fire command manningparty 249 Member of fort command manningparty 276 Member of gun battery manning party 76 Member of manning party— for minor armament 93 Member of mine command manning party 269 Meteorological, duties of 293-296 Scope of examination for 820 Selection of 61 Tested frequently 63 Tide, duties of 297 Obsekving station: Action taken when out of order 54 Gun battery , maiming party for 76 Mortar battery, maiming party for 87 Symbol for 673 Obturating primers 211 Obtukatoe: Deflnition 'y Inspection of 341 OmcEKS: Assignment of, by battery commanders 36 Assignment of, by mine commanders 34 Other than stafl, when not to be assigned 33 Relation in fort command 30 Where and how assigned by the battery commander 36 222 INDEX. Paragraph. Ogivo, definition - 742 Oil holes, inspection of 341 Oils for guns and carriages 409, 429 Operating boards, inspection of 341 Oednance department: Inspections hy oiScers of 334 Mat^rielfumished and maintained by 409 Regulations pertaining to property of 422-477 Ordnance officer. {See Coast defense ordnance officer.) Ordnance property and storeS; accountability of 327 Ordnance property, responsibility for 406 Oednance eepair shops: Appliances furnished by Ordnance Department 409 Control of 330 Use by artillery engineer 325 Use by quartermaster 333 Ordnance sergeant, at iingarrisoned fort i 473 Ordnance stores, for cleaning 409 Oeientation or mortaes 221,222 Metliods of testing 221 Out of commission defined 405 Out of service defined 405 P. Paint; For guns and caniages 409 To remove from guns and carriages 428 Painting: Carriages 426 Guns and mortars 425 Parade, battery, definition 597 Parade slope, definition 71S Parados, definition 719 Parapet, definition 720 Patrol, naval coast 2 Paulins: By whom furnished, 409 Regulations governing issue 468 Penetration, definition 721 Perforation, definition 722 Peesonwel: Assignment of 19-36 Of coast defense headquarters 300 J'ERSONNEL OFFICER: Fort command, duties of 2S4 Member of fort command manning party 276 Piece or gun, definition 634 Piece, service of, general instructions 203 Pintle center, definition 724 Pipe, equalizing, definition 661 Pipe, throttling, definition 786 Pit, definition 725 Pit commander: Duties of 69-71 Duties of, at 12-inch mortar drill 116 Tn charge of em])lacement 70 Responsibility of 69 Pit of mortar battery, by whom commanded 69 Pit salvo, definition 761 Pit section: Posting of, for 12-inch mortar drill 114 Twelve-inch mortar drill 110-117 Pits, marking ot 429 Plane of departure, definition 728 Planeof direction, definition 727 Plane of fire, definition 726 Plane of sight, definition 728 Plane of splash, definition 729 Platform, gun, definition 687 INDEX. 283 Platform, loading, deflnition Paragraph. Platform, subcahber, deimitioii ' 739 Platform, truck, dflfmition 707 Plotter; Duties of g^ Suties of, as member of gun baltery manning paiVy. . !! 80 Duties of, as member of mortar battery maiming pari y . . . g? Member of fire command manning party 249 Member of gun battery manning partj' '..........[. 76 Member of mine command mannmg party... 269 Memborofmortar battery manning party..! S7 Eesponsibility of q4 Scope of examination for 82o Plotter, assistant: Duties of, as member of gun battery manning party 80 Duties of, as member of mortar battery mannmg party ' 87 Member of gun battery manning party ' " 76 Member of mortar battery manning party....' 87 Plotting boakp: For fire commanders, description of 392 Tor guns, description of ' . 391 For mortars, description of 393 Plotting boom: Gun battery, manning party for 76 Mortar battery, manning party for 87 Symbol for 673 Plug, base, of projectile, deflnition 742 Plug, fuse, of projectile, deflnition 742 Point, datum, definition ' " 643 Point, directing, definition 660 Point of fall, deflnition 73O Point of impact, deflnition " 731 Point of splash, deflnition 732 Point, predicted, deflnition 737 Point, salvo, definition 762 Point, set forward, definition 765 Pointing: Deflnition, Case I, II, III 733 Methods of 223 Pointing tests 224-226 Position finder, definition 734 Position finding instrjments, installed by .. ', 409 Position finding system: Action taken when out of order 54 Definition 735 Powder: Not to be used for different calibers 233 Reporting on defective 234 Storage of, for sen'ice practice 232 Temperaiure of 232 PowPEK chamber: Cleaning during firing 238 Deflnition 736 Powder sections, how arranged 216 Powder serving tray 216,217 Powder storage cases, sealing of. 567, 668 Potvek equipment: Installation and maintenance of 408 Spare parts for 408 Power distribution lines, repaired by 318 Power bouse, symbol for 073 Power plants: Inspection of condition of electric installatio:i 341 Manaing table for 26 Eepaired by 318, 325 Supplies furnished by 411 Practice, service 230-245 Practice, subcaliber 229 Predicted point, definition 737 Predicter, definition . 73? 224 INDEX. Pbedicting: Paragraph. Gun battery 80 Mortar battery 90 Prediction tests for mortar batteries 227 Pressure gauge, definition 739 Pkimaet aem settee: Duties of, as member of gun battery manning party 80 Member of gun battery manning party 76 Primary station, definition 594 Primers: Definition 740 Delay in removal after misfire 242 Empty, care of 466 How inserlfid 208 Kind used at drill 207 Obturating 211 Removal of, after firing 236 Service friction, how used 209 Use of, when firing by electricity 243 Primers and fuses 523-528 Inspection of 528 Package 523 Storage and care 524-527 Priming charge or igniter, definition 741 Principles, general 1-18 Probable error, definition 664 Probable zone. (For definition, see Probable zone, 50 per cent.) Projectiles: Cleaning of, for target practice 235 Definition and description 742 Dummy, care of 465 Energy of. definition 658 Filled and fused 569-572 Inspection 572 Storage and care 569-571 Pilled but not fused 573, 574 Care of 573,574 Inspection 574 Loading 464 Packing boxes for 462 Painting of 463 Piling of 461 Seating of, at gun batteries of major armament 215 Travelof, definition 791 Propelling charge, definition 627 Pumping plantSj under control of 318 Q. Quadrants on mortars tested ». 222 Quartermaster Corps; Inspections by officers of 334 Supplies 411 R. Racer, definition 743 Radial vent, definition 803 Radio station, symbol for 673 Radiotelegraphy , where used for communication 365 Raising ropes, inspection of 341 Rammers, inspection of 341 Ramp, definition 744 Range, definition 745 Range and position finding system 74, 75 Range-azimuth table, definition 746 Range board: For guns of major and intermediate armament, description of 394 For guns of minor armament, description of 395 For minor armament 109 INDEX. 235 Range boabd operatoe: raragraph. Duties of, as member of gun battery 80 Member of gun battery manning party 76 Member of manning party of minor armament 93 Range, danger, definition 641 Range deviation, definition 647 Range differences, guns of major armament, where placed 220 Range officee: Duties of 67-60 Member of gun battery manning party 76 Member of mortar battery manning partj 87 Responsibility of 57 Range rake, definition 747 Range recorder, duties of 400 Ranges, moving target 62 Range setter, duties of, in connection witli time range board 400 Range table, definition 748 Ranging from one gun 98 Rapid-fire gim, definition 749 Rated men, definition 750 Rated posmoNs: Eligibility for 815,816 Regulations governing 813-820 Scope of examinations for 820 Readeb: Member of fire command manning party 249 Member of fort command manning party 276 Member of gun battery manning party 76 Member of mine command mannmg party 269 Member of mortar battery manning party 87 Rear slope, definition 751 Receiving table, definition 752 Recoil, definition 753 Recoil buffers, definition 755 Recoil ctlindees: Cleaning of 452 Definition 754 Inspection of 341 Recobds: Prediction tests lor mortar batteries 227 Range officer 60 Records of boards of examinations lor gunners 811 Records of daily attendance at drill 43 Records of examinations for special ratings 81 4 Rectangle, 25 per cent, definition 805 Reference numbers, definition 756 Regulations pertaining to Engineer Departmentliroperty 412-421 Regulations pertaining to Ordtoance Department property 422-477 Relocation of a target, definition 757 Repobts: By emplacement officer 67-68 By range officer 59 On iatemal combustion engines 320 Requisitions made by coast defense ordnance officer 328 Reserve detachmeht: Tlnee-inch gun drill 19> Four-inch gun drlU -.- - IS' Four and seven-tenths-inch gun driU 19^ Five-inch gun drill (barbette carriage) 184 Six-inch gun drill (barbette carriage).... 184 Six-inch gun driU (disappearing carnage). 161 ElghMnch gun drill (disappearing carriage) 161 Ten-inch gun drill (disappearing carriage) 151 Twelve-inch gun driU (barbette carriage) 171 Twelve-inch gun drill (disappearing carnage) 131 Twelve-inch mortar drill ; - • - - 113 Fourteen-inch gun drill (disappearing carnage) 131 Retracting 6-nich gun (disappearing carnage; 167 Rifling, definition 758 Rifling, twist of, definition SOI Eimbases, definition "59 104227°— 17 IS 326 INBEX Paragraph, Rollers, traversing, deflnition 795 Eotating band, deflnition 'ii2 Hound, deflnition (60 Rubber matting, supplied by ^08 Safety pin, inspection of 212 Salute: Firing of. 246-248 Made to iiispector 337-389 SalTO, deflnition 761 Salvo, battery, deiinition 761 Salvo, pit, deflnition 761 Salvo point, deflnition 762 Salvo table, deflnition 763 Sandpaper, use forbidden 449 Screw threads, inspection of lubrication of 341 Seacoast carriages, deflnition 617 Seabchlights 342-364 Areas, designation of 346 Assigned to fire commander 261, 348 Assigned to mine commander 348 Assignment, by whom 348 Classification of 344 Commands in use 356-358 Controlled by 345 Equipment, installation and maintenance c J 408 Equipment, spare parts for 408 Manning parties 353-356 Manning parties, drill of 354 Meaming table for 26 Night drill 342-364 Operation when searching 358 Repaired by 318 Standard 343 Symbol for 673 Tactical use of 342-352 Throwing on vessels 363 Used by fort commander 347 Use of, at night drills 360-364 Searchlight operator: Member of tire command manning party 249 Member of fort command manning party 276 Member of mine command roanning party 369 Qualifications for 356 Searchlight power plants, under care of 407 Searchlight watchers, qualifications for 355 Secondary arm setter: Duties of, as member of gun battery 80 Member of gun battery manning party 76 Secondary station, deflnition 594 Second-class gunner: Qualifying mark SIO Scope of examination for 812 Sections (op companies): Designation of 22-24 Dismissalof 41 Posting of 40 Service of information " i\ Service of security !"]* 11 Service of the piece, general instructions 203 Service practice 230-245 Serving table, definition ,.'. 764 Serving trays, wooden ; . 218 Set-forward point, definition 785 Sheaf ranging 99-101 WlieBn?«(J , TO7 INDEX. 227 Shell: Paragraph. Definition 742,700 Use of 6 Shell filler, definition 707 Shell room or shot room, definition 708 Shell tracer, definition 703 Shot: Definition 712,770 Use of - Shot gallery, definition 771 Shot hoist, definition 772 Shot hoist well, definition 773 Shot room or shell room, definition 708 Shot tongs, definition 774 Sight: Definition 775 Inspection of adjustment of 341 Telescopic, description of 397 Sight, line of, definition 704 Sight, plane of, definition 728 Sighting, bore 218-220 Sight standakd: Checking adjustment of 218 Definition 770 Signals: To point piece 213 Whistles and bugles authorized in giving 214 Signal Corps: Inspections by officers of 334 Supplies installed and maintained by 410 Signal stations: Equipment of 300 Manning table for 20 ■ Symbol for 073 Site, height of, definition 039 Sleeping rooms, inspection of 341 Slide rule, atmosphere, description of 381 Slope, centering, definition 022 Slope, exterior, definition 007 Slope, forcing, definition 078 Slope, interior, definition 695 Slope, parade, definition 718 Slope, rear, definition 751 Slope, superior, definition 782 Slope, traverse, definition 793 Slushing oil 409,423 Small tools, inspection of 341 Smokeless powder 653-508 CJianjini samples 564, 665 Inspection at forts 560, 50S Inspection by Ordnance Department 559 Package 553 Sealing powder cases 507, 668 Storage and care 554-558 Test with methyl violet paper 6S1-563 Speaking tube: Symbol for 673 Where used for communication 305 Specialists, enlisted, definition 060 Special ratings, examinations for 813-820 Splash, angle of, definition 587 Splash, plane of, definition 729 Splash, point of, definition 732 Sponges, inspection of 341 Spotter, member of mannini; party 93 Spotter, assistant, member of manning party 93 Spotting station: For minor armament 103, 104 Manninij party for 93 228 INDEX. Staff officers: Paragraph Assignment of _ 32 Detail of, as communication officers 33 For coast defense commander 300 For fire commander 257 For fort commander 283 For mine commander 274 Stop watches, furnished and maintained l-y 409 Storage rooms, inspection of ." 341 Striking velocity, definition 779 Structures, material for preservation 408 Subcaliber platform, definition 780 SUBCALIBER PRACTICE 229 Under emergency conditions 56 Subcaliber tube, definition 781 Submarine mine cable, when tested 326 Submarine mining structures, under care of 407 Superior slope, definition 782 Supplementary station, definition 594 Supplies, Quartermaster Corps 411 Supplies, Signal Corps 411 Supply departments 407-41 1 Supports, coast artillery, definition 634 Supports, coast artillery, use of 634 Support command, composition of 16 Support commander's headquarters, manning ta^ le for 26 Swasey depression position finder, adjustment of 389 Swell of the muzzle, definition 783 Switchboard, symbol for 673 Symbols, fire control 673 T. Table, delivery, definition 6^5 Table, elevation, definition 655 Table, range, definition 748 Table, range-azimuth, definition 746 Table, receiving, definition 752 Table, salvo, definition 763 Table, serving, definition 764 Taeg: Definition 784 Use of 80 Target, center of, definition 624 Targets: Furnished and maintained by 409 Indication and identification of 77-79, 88 Relocation of, definition 757 Target practice 228-245 Adjustments for 230 At command "Cease firing" 244 Care of gas-check seat 237 Cleaning of bore prior to target practice 231 Cleaning of projectiles prior to target practice 235 Inspection following 230 Insi)ection preceding 230, 241 Junior commander to hold fire 245 Misfire 242, 243 Report on defective powder ,234 Simulated, at inspection 341 Sponging after each shot 238 Temperature of powder 232 Use of ear protectors 240 Telegraphy, radio, where used for communication 365 Telephone: Care of 379 Testing of 373-376 Tests in selection of operators 367-372 Use of 377, 378 Where used for commtmication 365 Telephone line, symbol for 673 INDEX. 229 Paragraph.. TET^PHONE operator: xaiaKiaun Mffliiber of gun battery manning party 76 Member of mamiing party for fire commander's station ■■■:■,'■ 249 Member of manning party for fort commander's station . 276 Member of mannmg party for guns of minor armament. 93 Member of manning party for mine commander's station 269 Member of manning party for searchlights 353 Member of mortar battery manning party 87 Telescope, care of 467 Telescope, description of 396 Telescopic sight, description of . . 397 T^, pointing ]""[[[["'. 224-226 Thermometer: Description of 393 Fm"nisned and maintained by ' 499 Throttling bar, definition 735 Throttling pipe, definition .'."."." 786 Throttling valves, inspection of 341 Tide observer, duties of ' 297 Tide station: Manning table for 26 Regulations concerning 207 Symbol for 673 Time interval bells: Cutting off in drill 83 Definition !!]!!!!!!!!!!!!!!]]!]! 787 Time interval recorder ,,."]...!!! I ]! ! 788 Time interval system, description of 399 Time range board: Description of 400 Material for construction of 408 Tongs, shot, definition ['/_ 774 Top carriage, definition 739 Tools: Furnished by Ordnance Department 409 Special, furnished by Engineer Department 408 Tracer, Semple ]' lOg Tracer, shell, definition 769 Trajectory, chord of the, definition 630 Trajectory^ definition and explanation 790 Transmission device operator, member of manning party 93 Travel of projectile, definition 791 Traverse, definition 792 Traverse slope or wall, definition 793 Traversing circle, definition 794 TravCTsing mechanisms, inspection of 341 Traversing rollers, definition 795 Tray, loading, definition 707 Tray, powder serving, use of 216, 217 Trays, wooden serving 216 Tripping, definition 796 Trolley systems: Furnishing of spare parts 408 Installation and mamtenance of 408 Troops, Coast Artillery, proper use of 2 Troops, mobile, organization and mobilization of 3 TROTOL 54G-552 Inspection 551, 552 Package 546 Storage and care 547-550 What it can be stored with 550 Truck, ammunition, definition 579 Truck platform, definition 797 Trunnions, definition 798 Trunnions, axis of, definition 590 Tru nn ion band, definition 799 Tube, definition 800 Tube, subealiber, definition 781 Tugs, by whom supervised 307 Twist of rifling, definition Sni 230 INDEX. u. r-r , Paragraph. Underground communication lines, installed by 408 Uniforms, inspection of 341 Units, t-actical chain of Coast Artillery command 12 V. Vane, wind, description of 402 Velocity, definition 802 Velocity, muzzle or initial 716 Velocity, remaining, definition 802 Velocity, striking, definition 779 Vent, definition 803 Vent, axial, definition 803 Vent, radial, definition 803 Vertical base system: Definition 74 Use for gun battery Sl-83 Use for mortar battery , 92 ^V. Wall, corridor, definition 636 Wall, interior, definition 696 Wall, traverse, definition 793 Water areas, division of 302 Well, counterweight, definition (538 Well, shot hoist, definition 773 Whistles used in signaling 214 Wind component indicator, description of 401 Wind vane, description of 402 Wiring for nring circuits on carriages, installed by 409 Wiring for illuminating circuits on carriages, installed by 409 Wooden serving trays, where used 216 Z. Zone, definition 804 Zone, 50 per cent 805 Zone, probable, definition 805 Zone, umer defense, definition 804 Zone, outer defense, definition 804 ADDITIONAL COPIES OF THIS PUBLICATION MAY BE PROCURED FROM THE SUPERINTENDENT OF DOCUMENTS GOVERNMENT PRINTING OFFICE WASHINGTON, D. C. AT 60 CENTS PER COPY V