CHAPTER IV.

GUN-COTTON.—HOW PACKED.—STOWAGE.—CARE.—INSPECTION AND DRYING.

PACKING AND STOWAGE OF WET GUN-COTTON.

Each Service Torpedo, completely filled with wet gun-cotton, is packed in a rough box for transportation and stowage. The Exercise Torpedoes, ten filled with wet gun-cotton and two empty, are packed six in a box.

Each filled torpedo has attached to its case a tag on which is marked the gross weight of the torpedo in pounds and ounces, the initials of the Superintendent of the Gun-cotton Factory and the factory number of the charge from which the contained gun-cotton is taken.

When received on board ship the cover on which the address is marked is to be reversed. The torpedoes are then stowed in the magazine in a manner similar to that now employed in stowing shells.

MARKS ON BOXES.

+-----------------------+------------------------+ | PAT. D. TORPEDO, | PAT. D. TORPEDOES, | | SERVICE. | EXERCISE. | | | | | = .... LBS. DRY G. C. | = .... LBS. DRY G. C. | | | | |(_Factory No. of_ | (_Factory No. of_ | | __Charge._) | _Charge._) | +-----------------------+------------------------+

PACKING-AND STOWAGE OF DRY GUN-COTTON.

The glass jars for dry primers, filled with dry gun-cotton, are put in wooden cases, painted white, fitted with sliding covers as described on p. 13. The cases are marked “DRY GUN-COTTON PRIMERS. NOT TO GO BELOW.” They are packed in a rough box for transportation.

When received on board ship the cases containing the jars are placed in different parts of the ship, but are never to be stowed below the water-line.

On account of insurance restrictions imposed on freight companies it is often impracticable to ship gun-cotton in its dry state. When this is the case the gun-cotton primers are issued wet and are packed in the spare exercise torpedo-cases from which, on receipt aboard ship, they are to be removed and dried and then stowed in the glass jars for dry primers.

* * * * *

A Torpedo Outfit, consisting of 24 Service, Pattern D. Torpedoes, 12 Exercise (10 filled, 2 empty), Pattern D. Torpedoes and 4 jars of dry gun-cotton for primers will contain, approximately, the following amount of gun-cotton:—

WET GUN-COTTON.

24 Service Pattern D,} {1296 2-inch blocks; or 1200} Torpedoes }={ 2-inch blocks and 384 }wet = 818.1 lbs. } { ½-inch blocks } dry.

12 Exercise (10 full,} {60 2-inch blocks; or 50 } 2 empty) Pattern D,}={ 2-inch blocks and 40 }wet = 37.9 lbs. Torpedoes } { ½-inch blocks } dry.

} {1356 2-inch blocks; or 1250} Total wet gun-cotton }={ 2-inch blocks and 424 }wet = 856 lbs. } { ½-inch blocks } dry.

DRY PRIMERS.

6 each of {16 ½-inch blocks;} {96 ½-inch blocks;}dry = 15.2 lbs. dry. {or 4 2-inch blocks }={or 24 2-inch blocks} ----- Total equivalent of dry gun-cotton in outfit 871.2 lbs. dry.

The wet charge of a torpedo, Pattern D, is composed of blocks two inches thick. The primer charge is composed of blocks ½ inch thick, if there be any on hand; otherwise, of blocks 2 inches thick.

The 2-inch block contains 10.1 oz. and the ½-inch block 2.5 + oz. of dry gun-cotton.

CARE OF GUN-COTTON AND DETONATORS.

=The Gun-Cotton Magazine= must not be located near the boilers or engines, nor where the temperature of the magazine will equal 105° F. for any great length of time. The magazine should be aired frequently. Avoid as much as possible exposing any box or case containing gun-cotton, dry or wet, to the direct rays of the sun for any length of time, as the temperature inside the box can, in this way, be raised to a point considerably above that of the open air and this temperature will be maintained for a considerable time after the exposure.

The diurnal changes of temperature will not affect gun-cotton, wet or dry, provided that the cases or boxes containing the gun-cotton are not exposed to the sun.

The detonating charges of dry gun-cotton are designated “primers,” and the fulminate of mercury igniter as the “detonator.”

The primers of dry gun-cotton supplied to each ship are packed in glass jars with tight covers to exclude moisture. Strips of blue litmus-paper are placed between the blocks of dry gun-cotton.

The glass jars will be kept in their wooden cases. The jars and cases are a part of the permanent outfit and must be cared for and returned. Dry gun-cotton is never to be stowed below the water-line, but it may be carried under any deck above the water-line, care being taken that the glass jars, in their wooden cases, are not within 10 feet of each other, nor in the vicinity of the galley or other fires, nor in the immediate vicinity of the guns of the battery.

In removing from their cases the glass jars holding the dry gun-cotton never expose them to the sun, as the glass may act as a lens and cause the ignition of the gun-cotton.

All other primers will be furnished wet, and packed in the torpedo cases.

As the stock of dry primers becomes reduced, a suitable time and place will be selected for replenishing the stock, by drying, according to the rules for drying gun-cotton, the blocks removed from the torpedoes in priming them.

The detonator has a charge of 35 grains of fulminate of mercury. Detonators are placed in circular wooden blocks, bored to hold eight each, each block being put in a tin box. These tin boxes should never be put below the water-line, but kept in a dry place on the upper decks, and not in the immediate vicinity of the galley or other fires, of the battery, or of other explosives. _All loaded detonators are painted red_, and the tin boxes containing them are also painted red and marked on top “DANGEROUS.” Great care should be taken to grasp the box by the bottom when lifting or carrying it for, if held by the top only, the bottom, with its block, may slip out.

INSPECTION OF GUN-COTTON.

_Weekly—all dry gun-cotton._ _Monthly—all dry gun-cotton._ _Quarterly—all wet gun-cotton._

INSPECTION OF DRY GUN-COTTON.

=Weekly Inspection.=—_The dry gun-cotton primers must be inspected weekly._ This can be done without opening the jars, by observing the condition of the blocks and the strips of blue litmus-paper placed between them.

In the event of any serious decomposition having taken place, the gun-cotton will be found more or less covered with pasty, yellow spots, the jar will be filled with brownish red, highly acid fumes and the litmus-paper will show a decided red color. In this event the gun-cotton may be thrown overboard, but even when in this extreme condition there appears to be little danger of immediate explosion and, if desired for use, this gun-cotton may be wet with the alkaline solution (p. 45), until it has increased 30% in weight, and used as wet gun-cotton. No serious risk will attend this operation. No gun-cotton should be thrown overboard except when a board of experts has pronounced it to be in the condition above described. This is essential, as considerable valuable gun-cotton has been condemned and destroyed and a sense of insecurity has arisen in consequence of errors in inspection.

It frequently occurs that the blue litmus-paper becomes faded by exposure in the jars, but no danger is to be apprehended in consequence.

If the litmus-paper has become reddened, but no fumes or pasty spots are observed, the blocks should be lifted out by the loose ends of the tape and placed on a perfectly clean, dry piece of blotting-paper. Then untie the tape and separate the blocks, being careful not to touch them with the fingers. (A perfectly clean, dry crash towel may be used in handling the blocks.) Remove the strips of litmus-paper, insert freshly moistened strips in their places and tie the tape as before. After an hour‘s interval examine the ends of the strips of litmus-paper. If they have become reddened, wet the blocks with the alkaline solution (p. 45), until they have increased 30% in weight and use them as wet gun-cotton.

If the moistened litmus strips have not become reddened after one hour‘s exposure, replace the blocks in the jar, close it tight and replace it in its box.

=Monthly Inspection.=—Even if no change is observed in the litmus-paper at the weekly inspections the test just described, with freshly moistened blue litmus-paper strips, is to be applied to all dry gun-cotton once each month and this constitutes the _monthly inspection_. If the test shows the gun-cotton to be acid, the gun-cotton should be wet with the alkaline solution (p. 45), until it has increased 30% in weight, and then used as wet gun-cotton.

INSPECTION OF WET GUN-COTTON.

=Quarterly Inspection.=—The wet gun-cotton is packed in the Service and Exercise cases and contains from 30% to 35% of water. The gross weight of gun-cotton and case is marked upon each case. These cases are to be separately weighed every three months and any loss in the gross weight made up by the addition of pure water poured through the filling-hole, which should then be carefully closed.

PRECAUTIONS TO BE TAKEN IN INSPECTION.

Do not handle the gun-cotton with the bare hand. Never touch litmus-paper with the bare hand. Blue litmus-paper may become reddened by the acid substances exuded from the skin. Litmus-paper should always be handled with the forceps provided in the Chemical Box.

Always moisten the litmus-paper before making the test, using the distilled water provided in the Chemical Box. Hold the litmus-paper strip in the forceps, dip one of the glass rods, provided in the Chemical Box, in the bottle of distilled water and then apply the moist rod to the paper. The litmus-paper must be moist, only, and not reeking with water. Should the supply of water in the Chemical Box be exhausted, water distilled on board, or fresh rain water, may be used, provided it first be tested and found free from acid reaction.

Make a comparative test to prove that there is, or is not, an acid reaction. As blue litmus-paper may sometimes become slightly reddened when moistened with distilled water only, a comparison should always be made by taking two pieces of fresh blue litmus-paper and moistening one with distilled water and the other with dilute vinegar.

Always examine the test papers by white light. Litmus-paper will present a reddish appearance in any apartment that is shellacked or colored; the examination of test papers should therefore be made only in a light room or in the open air.

Do not mistake iron rust for pasty yellow spots. Gun-cotton sometimes becomes rusted in the course of manufacture, or from the cases in which it is packed. The rust does no harm.

Avoid unnecessary handling of the blocks, as they are apt to flake and crumble.

ALKALINE SOLUTION.

The alkaline solution referred to above is made by dissolving four ounces of dry carbonate of soda in one gallon of rain or distilled water. When it is found necessary to wet dry gun-cotton this solution may be poured into the jar holding the blocks.

RULES FOR DRYING GUN-COTTON.

Wet gun-cotton primers can be dried by any of the following methods:—

1. Exposure in a steam-drier. 2. ” to calcium chloride. (Ca Cl₂). 3. ” in a dry atmosphere.

The quantity of dry gun-cotton primers that are furnished being very small, the stock should be replenished as fast as used by drying the wet blocks removed from the torpedoes in priming them.

DRYING BY EXPOSURE IN A STEAM-DRIER.

The steam-drier must be located above the water-line, remote from fires and lamps and where it will not be subject to disarrangement. Its supply of steam is to be derived from a suitable part of the steam-heating apparatus of the ship or from any other convenient source of low-pressure steam by piping fitted at the Navy Yard.

The blocks to be dried are separately weighed, the weight of each marked on it with a soft lead-pencil (never putting labels of any kind on the gun-cotton) and then strung on the rods, with the iron washers strung between adjacent blocks, and placed in the baskets of the drier. The baskets are put in the drier, the door is closed, the thermometer put in place, steam is turned on and the ventilating openings are adjusted.

The baskets, rods and washers must be kept free from dirt and oil.

The temperature of the drying chamber must not exceed 100° F.

After each day‘s heating carefully remove and weigh each block, re-mark it and proceed with the drying.

This process should be continued until the blocks no longer lose weight, when all but a small percentage of moisture will have been expelled. It has been found by experiment, however, that gun-cotton containing as much as 13% of water can be relied on to detonate, the service fulminate of mercury detonator being used.

When the drying is complete remove the blocks from the drier, place them, while still warm, in the glass jars, with strips of blue litmus-paper between them and close the jars tight. They will then be stowed and inspected as dry gun-cotton.

If the process of drying is not continuous the blocks must be kept in a powder tank, closed tight, when the drier is not in operation.

DRYING BY EXPOSURE TO CALCIUM CHLORIDE (Ca Cl₂).

This method requires:—5 lbs. calcium chloride (Ca Cl₂), 1 empty powder tank and 3 baking pans.

The calcium chloride (Ca Cl₂) is cheap and can readily be obtained from any dealer in chemicals; it must not be confounded with chloride of lime or bleaching powder (CaO₂Cl₃). The latter has a strong odor of chlorine and, if used instead of the calcium chloride (Ca Cl₂), might cause decomposition of gun-cotton. The former is odorless and has no bleaching properties. To distinguish whether the substance has any bleaching properties, stir a small portion in an equal volume of water and immerse a piece of blue litmus-paper in the mixture. If the color disappears from the paper when dry (turning white), the substance is chloride of lime or bleaching powder (CaO₂Cl₂) and must not be used.

The powder tank can be readily procured on board ship; care must be taken that it closes easily and air-tight.

The baking pans should be of such a size that three of them will cover the bottom of the tank when placed alongside of each other; made of stout tin, free from solder, and 5 to 6 inches deep.

Divide the calcium chloride between the three pans and place these pans, which must be clean and free from oil or grease, in the oven of the galley and allow them to remain there until all traces of moisture disappears. Stir the calcium chloride occasionally with a clean metal rod to expose the lower particles. Break it into pieces the size of a pigeon‘s egg. When all traces of moisture have disappeared remove the pans to a dry place and allow them to cool. The calcium chloride must not be put in the tank, nor the gun-cotton exposed to it, while warm. Place the tank in some suitable location where it will not be disturbed and, when the calcium chloride is cooled, place the pans in the bottom of the tank and lay over them a copper sieve, tinned copper wire being the best. Then place the blocks to be dried on the sieve and close the tank. Open the tank every 3 or 4 days, weigh the blocks, marking the weight and date with a soft lead-pencil on them and dry the calcium chloride as before. Continue this until the blocks have ceased to lose weight. While the calcium chloride is drying, the blocks are to be kept in the tank, which must be closed to exclude the moisture in the air. When they have ceased to lose weight stow them in the glass jars for dry gun-cotton primers, taking care to lay between them strips of blue litmus-paper, and treat them according to the rules laid down for dry gun-cotton.

This operation is independent of the condition of the atmosphere and only requires the care mentioned.

DRYING BY EXPOSURE IN A DRY ATMOSPHERE.

String the blocks to be dried on a wood, brass or copper rod or pipe, which must be free from dirt and oil, or place them on a shelf made of wire netting, separating the blocks from each other to expose all surfaces freely to the air; suspend the rod or shelf in some suitable place not in the vicinity of the galley or other fires, where the blocks will be freely exposed to the air, and be under cover.

Expose the blocks only when the atmosphere is dry; at all other times keep them in an empty powder tank, in the immediate vicinity of the place selected for drying, kept closed to exclude moisture. Weigh the blocks every two days, noting the date and weight with a soft lead-pencil on them. Continue the drying until the blocks show no loss of weight for two consecutive weighings; then place them in the glass jars, with strips of blue litmus-paper between, and treat them according to the rules given for dry gun-cotton primers.

This plan can only be carried out in dry climates.

Avoid unnecessary handling of the blocks, as they are apt to flake and crumble.

MISCELLANEOUS DATA.

Dimensions of gun-cotton blocks

length 2.9 inches. width 2.9 ” height { 2.0 ” for full sized blocks, { 0.5 ” for primer blocks.

Diameter of detonator hole = ⁷/₁₆ inch.

Pressure applied to blocks in the final press = 6800 lbs. per square inch.

Average gravimetric density of compressed dry gun-cotton = 1.287.

Average weight of one cubic inch of compressed dry gun-cotton = 325 grains, = 0.743 oz.

Weight of water added to each pound of dry gun-cotton when issued to the service as wet gun-cotton (approximately 35%) = 0.35 lb. = 5.6 oz.

APPENDIX.

DUTIES OF THE INSPECTOR OF ORDNANCE.—LIST OF ARTICLES IN OUTFIT, WEIGHTS AND STOWAGE SPACE.

DUTIES OF THE INSPECTOR OF ORDNANCE AT THE NAVY YARD IN CONNECTION WITH THE TORPEDO OUTFIT OF A SHIP.

GUN-COTTON MAGAZINE.

He will carefully inspect the gun-cotton magazine, satisfy himself that it is constructed in accordance with the Ordnance Instructions concerning shell-rooms, and the directions given on pages 40 and 41 Spar-Torpedo Instructions, that it is of sufficient size to stow the portion of the torpedo outfit defined in the “Table showing Weight, Space and Place of Stowage of Articles in Spar-Torpedo Outfit” and will prepare a plan of stowage.

TORPEDO STOREROOM.

He will carefully inspect the torpedo store-room, satisfy himself that it is in a proper position with regard to battery and boilers, that it is not exposed to undue changes of temperature, or to accidental admission of water, and that it is of sufficient capacity and conveniently arranged to stow the portion of the outfit defined in “Table showing Weight, Space and Place of Stowage of Articles in Spar-Torpedo Outfit.”

BATTERY LOCKER.

He will carefully inspect the battery locker and see that it is in a proper position with regard to the great-gun battery and the boilers. It should, preferably, be in a good light.

SHIP‘S SPARS AND FITTINGS.

He will, while the ship‘s spars and fittings are being made and when they are in place, inspect them carefully, satisfy himself that the spar-bands are properly spaced and in line to receive the secondary spar and report to the Bureau the position and class of the heel fittings and the leads of topping-lifts and guys, with his opinion of their efficiency and convenience.

PERMANENT WIRES.

He will ascertain what firing apparatus the Bureau intends to place on board and make a requisition for the necessary wire and terminals.

Upon the receipt of these articles he will locate the firing apparatus and prepare and place the permanent wires and terminals.

He will cause a plan showing the lead of the different wires to be made, and will send copies to the Bureau and to the Torpedo Station, and will furnish one to the commanding officer of the vessel.

No fixed rules can be given for leading permanent wires. The general method of leading the upper-deck wires, manner of securing to terminals and precautions to be observed, are given on pages 14 and 15. Permanent wires should also be led from the battery to the firing-point on the bridge or elsewhere. In case of electrical gun-circuits being desired, special directions or plans will be issued by the Bureau of Ordnance.

LIST OF ARTICLES IN SPAR-TORPEDO OUTFIT SUPPLIED FROM THE TORPEDO STATION.

The Spar-Torpedo Outfit for ships having one torpedo boat comprises the articles given in the list. Ships having two or more torpedo boats will have the articles in the Boat‘s Outfit, necessary to the simultaneous use of all the boats, increased proportionally.

Ship‘s Boat‘s and Outfit. Boat‘s Outfit. BOX 1. 1 Farmer‘s D. E. machine, Pattern A, containing:— 1 Firing-key. 2 Machine connecting-wires (12 feet long). 1 Crank.

BOX 2. 1 1 Reel box, containing:— 300 300 Feet double-conductor insulated cable. 1 1 Crank.

BOX 3. 1 1 Supply-box, containing:— 1 1 Monkey wrench. 3 3 Open-end wrenches.—One end fits the screw-cover of the torpedo-case; the other, the screw-bolts that secure the spindle. 1 1 Rectifier,—a wooden rod, marked in inches, for lining the blocks in the primer-case. 6 12 Pieces of emery cloth,—for brightening wires and removing rust. 1 2 Pairs of cutting plyers,—for general use in cutting and working wires. 1 2 Pieces of okonite tape,—for insulating naked wires when not exposed to water. 2 2 Earth-plates,—copper plates (coated with tin to prevent rust). 12 24 Pieces of rubber tubing,—for insulating splices. 1 1 Sample splice,—for instruction. 1 2 Spools of hemp twine,—for securing rubber tubing. 1 2 Knives,—for cleaning wires and for general use. 1 1 Screw-driver,—for general use. 6 12 Dummy detonators (painted white),—for instruction. 1 1 Sample detonator splice,—for instruction. 1 1 Dummy gunpowder fuze,—for instruction. 24 36 Spherical rubber packings. 36 36 Paper fasteners. 2 2 Safety-pins for circuit-closer (spare). 1 1 Spring for circuit-closer (spare). 1 1 ⅜ by 16 screw-tap,—to cut a thread for spar screws. 12 12 Screws for boat‘s steel spars,—to secure the two parts of a boat spar. 4 4 Reeving-lines,—for reeving leading-wires through the boat‘s spars. 2 2 Reeving-line weights,—to reeve the reeving-lines through the boat‘s spars.

BOX 4. 1 Wire-box, ship‘s, containing:— 4 Spar leading-wires. 2 Machine connecting wires-(12 feet long, spare).

BOX 5. 4 Spar-bands with key-ways. 4 ” (ordinary). 24 Wood screws.

BOX 6. 4 8 Tin boxes, containing:— 4 8 Detonator-blocks. 32 64 Detonators.

BOX 7. 32 32 Gunpowder igniters. 18 18 ” fuzes.

BOX 8. 2 4 Glass jars with corks, containing:— 12 24 Blocks dry gun-cotton.

BOX 9. 1 Testing and firing plate (when specially ordered).

BOXES 10 AND 11. 12 Secondary spars, ship‘s. 12 Keys for same.

BOXES 12 AND 13. 12 12 Secondary spars, boat‘s. 12 12 Toggles for same.

BOX 14. 1 1 Farmer‘s D. E. machine, Pattern C, containing:— 2 2 Machine connecting-wires (12 feet long). 1 1 Crank.

BOX 15. 1 1 Wire-box, boat‘s, containing:— 4 4 Spar leading-wires. 2 2 Machine-connecting wires (12 feet long, spare). 4 4 Secondary spar caps. 4 4 Rivets for same. 4 4 Secondary spar butts. 4 4 Rivets for same.

BOX 16. 1 1 Chemical box, containing:— 2 2 Pair forceps. 2 2 ” scissors. 2 2 Bottles distilled water. 2 2 ” for litmus-paper. ½ ½ Quire litmus-paper. 1 1 Tin cylinder for same. 2 2 Pounds carbonate of soda (dry). 1 1 Piece boiled tape. 2 2 Glass rods.

BOX 17. 2 2 Spar clamps. 1 1 Set of boat-fittings, Pattern B, as follows:— 2 2 Heel-rests. 2 2 Hinge-plates. 2 2 ⅝ bolts with nuts,—for securing heel-rests to hinge-plates. 2 2 Swivel-crutches,—each with a hinged top and two rollers, secured together by studs, rivets and pins. 2 2 Bearings secured to crutches with bolts and washers. 1 1 Cross-beam with two bearings riveted on. 2 2 Hoods, (right and left),—each fitted with two bolts for securing to the cross-beam. 2 2 Securing rods,—for securing elevating-arms to cross-beam. 2 2 Elevating-arms with cog-wheels attached. 2 2 Plate washers,—for holding elevating-arms on cross-beams. 2 2 Nuts on ends of securing rods,—to hold washers in place. 2 2 Guide rings,—each fitted with a roller secured by studs and split pins. 2 2 Screw-nuts,—each fitted with a lock-screw, to secure guide rings to elevating-arms. 2 2 Worm shafts,—each in two parts, joined by a hook-coupling. 2 2 Elevating-wheels,—with pins for securing same to worm shafts. 2 2 Clutches, consisting of the following parts:— 2 2 Bearings. 2 2 Sleeves,—with trunnions and lugs. 2 2 Yoke-links. 2 2 Detaching-levers,—each with transverse roller attached. 2 2 Pins,—for locking detaching-levers. 4 4 Bolts with split pins,—for securing parts of clutch together. 16 16 ⅝ bolts,—for securing hinge-plates, swivel-crutch bearings and clutch-bearings to boat.[1] 16 16 ⅝ phosphor-bronze nuts for same. 4 4 ¾ bolts,—for securing cross-beam bearings to deck.[2] 4 4 ¾ phosphor-bronze nuts for same.

BOX 18. 1 1 Testing magneto.

BOXES 19 TO 22. (_Both inclusive_). 2 2 Boat spars. 2 2 Canvas bags for same.

BOXES 23 TO 46. (_Both inclusive_). 12 24 Service Torpedoes, Pattern D.

BOXES 47 AND 48.

BOXES 49 AND 50. 12 12 Exercise Torpedoes, Pattern D, (two of which are empty).

BOXES 51 AND 52.

BOX 53. 12 24 Service Torpedo spindles. 12 12 Exercise ” ” 24 36 Torpedo pins. 4 8 ” ” (spare).

BOX 54. 1 Ship‘s firing-battery. 1 Battery tester (6.5 ohms). 1 1 Boat‘s firing-battery. 2 2 Spare cells for same. 1 1 Battery tester (4 ohms). 1 2 Hand-firing keys. 3 5 Pounds sal-ammoniac. 12 12 Spare fuze bridges,—for testing batteries.

BOX 55. 1 1 Steam-drier.

BOX 56. 4 4 Circuit-closers,—for Contact Torpedo. 4 4 Spherical rubber packings for same. 4 4 Rubber diaphragms for same. 16 16 Brass screws,—for attaching circuit-closer.

BOX 57. 1 1 Contact spar leading-wires. 2 2 Rubber diaphragms (spare). 12 12 ” washers,—for Exercise Torpedo (spare). 12 24 ” ” —for Service Torpedo (spare). 4 8 Spherical rubber packings (spare). In addition to the above, if no testing and firing-plate is furnished, 2 Electric switches.

[1] =_Note._=—These bolts are supplied at the Navy Yard where the boats are fitted.

[2] =_Note._=—These bolts are supplied at the Navy Yard where the boats are fitted.

Two Copies of the Torpedo Instructions, corrected to date of issue, will be furnished to each vessel receiving a torpedo outfit.

These copies will be sent by mail, simultaneously with the issue of the outfit, addressed to the Inspector of Ordnance at the Navy Yard at which the vessel is fitted out.

* * * * *

This book is corrected to

* * * * *

Terminals and insulated wire for permanent wires will be furnished as required.

The Bureau of Ordnance will designate which of the following will be supplied:—

2 Electric switches. 1 Testing and firing-plate.

SUPPLIED FROM NAVY YARD. Torpedo-spars for ship. Fittings for same. 16 16 ⅝ bolts,—for securing boat-fittings to boat. 4 4 ¾ ” ” ” ” ” ” ”

=_Note._=—Boxes 6, 7, 8, 23 to 46 inclusive, 49 and 50, contain explosives, which must be stowed as directed in the Instructions. Boxes 8 and 16 contain glass and are to be handled with care. Boxes 2, 4, 15 and 57 contain insulated wire and must be stowed in a cool place to guard against deterioration of the insulation. All other boxes must be stowed in a dry place and the contents kept free from rust.

+---------------------------------------------------------------+ | Table Showing Weight, Space and Place of Stowage of Articles | | in Torpedo Outfit. | +===========+========+==================+===========+===========+ | | | | | | | |Invoice |OUTSIDE DIMENSIONS|Approximate|Approximate| | WHERE | number | OF BOX IN INCHES | cubical | gross | | STOWED. |of boxes+------------------+ space of | weight of | | | | L. W. D. | each box | each box | | | | | | | +-----------+--------+------------------+-----------+-----------+ | | | | Cu. ft. | Lbs. | |GUN-COTTON |23 to 26| 11.8 11.8 17.8 | 1.4 | 72. | | MAGAZINE. | 49, 50 | 13.8 12.9 17. | 1.8 | 66. | +-----------+--------+------------------+-----------+-----------+ | | 1 | 16. 13.5 20.5 | 2.6 | 146. | | | 2 | 18.5 15.2 17.5 | 2.8 | 92. | | | 3 | 20. 16. 10.5 | 1.9 | 48. | | | 4 | 16.5 16.5 16. | 2.5 | 67. | | | 10, 11 | 98.5 14. 5. | 4. | 222. | | | 12, 13 | 102. 21. 6. | 7.4 | 230. | | | 14 | 12.6 11. 16.5 | 1.3 | 54. | | TORPEDO | 15 | 16.6 16.6 16. | 2.6 | 68. | |STOREROOM. | 16 | 19. 11.6 12.6 | 1.6 | 30. | | | 17 | 86.5 15.3 18. | 13.8 | 400. | | | 18 | 7.8 5.3 7.5 | .2 | 9. | | +--------+------------------+-----------+-----------+ | |19 to 22| 219. 8.5 6.5 | 7. | 205. | | | | 183. 8.5 6.5 | 5.8 | 170. | | +--------+------------------+-----------+-----------+ | | 53 | 19.8 11.6 15.1 | 2. | 105. | | | 55 | | | | | | 56 | 24.6 13. 8.2 | 1.5 | 43. | | | 57 | 19.5 18.5 6.6 | 1.3 | 28.5 | +-----------+--------+------------------+-----------+-----------+ | BATTERY | 54 | 15. 10.5 11.5 | 1. | 37.5 | | LOCKER. | | | | | +-----------+--------+------------------+-----------+-----------+ |IN PLACE ON| 5 | 21. 16.5 7.5 | 1.5 | 80. | | SPARS.| | | | | |” ” ” DECK.| 9 | 52. 18.5 18.5 | 10.4 | 155. | +-----------+--------+------------------+-----------+-----------+ |SEE | 6 | 9.8 9.7 6.8 | .4 | 10. | |REGULATIONS| 7 | 12.2 10.2 5.2 | .4 | 11. | | FOR SAME. | 8 | 8.2 14.2 17.5 | 1.2 | 25. | +-----------+--------+------------------+-----------+-----------+

+===========+========================++=========================+ | | BOAT‘S OUTFIT ||SHIP‘S AND BOAT‘S OUTFIT.| | |------+-------+---------++------+-------+----------+ | WHERE |Number| Total | || | Total | | | STOWED. | of |approx.|Aggregate||Number|approx.| Aggregate| | | boxes|cubical| weight || of |cubical| Weight | | | | space | || Boxes| space | | +-----------+------+-------+---------++------+-------+----------+ | | |Cu. ft.| Lbs. || |Cu. ft.| Lbs. | |GUN-COTTON | 12 | 16.8 | 864. || 24 | 33.6 | 1728. | | MAGAZINE. | 2 | 3.6 | 132. || 2 | 3.6 | 132. | +-----------+------+-------+---------++------+-------+----------+ | | | | || 1 | 2.6 | 146. | | | 1 | 2.8 | 92. || 1 | 2.8 | 92. | | | 1 | 1.9 | 48. || 1 | 1.9 | 48. | | | | | || 1 | 2.5 | 67. | | | | | || 2 | 8. | 444. | | | 2 | 14.8 | 460. || 2 | 14.8 | 460. | | | 1 | 1.3 | 54. || 1 | 1.3 | 54. | | TORPEDO | 1 | 2.6 | 68. || 1 | 2.6 | 68. | |STOREROOM. | 1 | 1.6 | 30. || 1 | 1.6 | 30. | | | 1 | 13.8 | 400. || 1 | 13.8 | 400. | | | 1 | .2 | 9. || 1 | .2 | 9. | | +------+-------+---------++------+-------+----------+ | | 2 | 14. | 410. || 2 | 14. | 410. | | | 2 | 11.6 | 340. || 2 | 11.6 | 340. | | +------+-------+---------++------+-------+----------+ | | 1 | 2. | 105. || 1 | 4. | 172. | | | 1 | | || 1 | | | | | 1 | 1.5 | 43. || 1 | 1.5 | 43. | | | 1 | 1.3 | 28.5 || 1 | 1.3 | 28.5 | +-----------+------+-------+---------++------+-------+----------+ | BATTERY | 1 | 1. | 36.5 || 1 | 1.9 | 70.5 | | LOCKER. | | | || | | | +-----------+------+-------+---------++------+-------+----------+ |IN PLACE ON| | | || 1 | 1.5 | 80. | | SPARS.| | | || | | | |” ” ” DECK.| | | || 1 | 10.4 | 155. | +-----------+------+-------+---------++------+-------+----------+ |SEE | 1 | .4 | 10. || 1 | .7 | 20. | |REGULATIONS| 1 | .4 | 11. || 1 | .4 | 11. | | FOR SAME. | 1 | 1.2 | 25. || 1 | 2.2 | 49. | +-----------+------+-------+---------++------+-------+----------+

INDEX.

After guy—ship‘s torpedo spar, 16 Alkaline solution, 45 Amount of water in wet gun-cotton, 44 Apparatus for drying gun-cotton, 13, 47, 48, 49 Articles for testing gun-cotton. (See Chemical box). ” list of in outfit, 52 ” of torpedo outfit supplied at Navy Yard, 15, 56 ” ” ” ” ” from Torpedo Station, 14, 52 ” spare, 1, 14

Bands, spar, 8, 53 Batteries, firing. (See Firing-batteries). Battery-cell, description, 27 ” cells, spare, 27, 55 ” locker, 51 ” tester, 28, 55 Blocks, detonator, 11, 53 ” primer, dry, 12, 39, 40, 41, 49, 53 Boat, firing-batteries. (See Firing-batteries). ” fittings, Pattern B, 8, 9, 10, 54, 55 ” spar. (See Spar). ” to test the circuit from, 21 ” wire-box, 7, 54 Bow-fittings, 8, 54 Box, chemical, 13, 54 ” gunpowder fuzes and igniters, 12, 53 ” reel, 6, 52 ” stuffing, 3 ” supply, 8, 52 ” torpedo packing, 39 ” wire, boats, 7, 54 ” ” ships, 6, 7, 53 Butts, secondary spar, 5, 54

Cable, insulated. (See Reel box). Caps, secondary spar, 5, 54 ” ” ” rivets for, 54 ” water. (See Stuffing-boxes). Care and management of firing-batteries, 29 ” of gun-cotton and detonators, 41 Case, primer. (See Primer-case). Cell, battery, 27 Cells, battery, spare, 27, 55 Charge, detonator, 10, 42 ” primer, dry. (See Primer charge). Calcium, chloride. (See Chloride of calcium). Chemical box, 13, 54 Chloride of calcium, 47 ” ” ” how distinguished from chloride of lime, 47 ” ” ” test of, for bleaching properties, 47 ” ” ” to be used instead of chloride of lime, 47 ” ” lime. (See Chloride of calcium). Circuit-closer, Pattern B, description, 4 ” ” ” ” how attached, 4, 22 ” ” ” ” test, 22, 23 ” ” ” ” necessary to be water-tight, 23 ” ” ” ” number issued, 4, 56 ” ” ” ” safety-pin to be in before priming, 23 ” ” ” ” to be tested before priming, 23 ” ” safety-pins, spare, 53 ” ” spring, spare, 53 ” ” weight of, 5 Circuit testing, from ships, 20 ” to test the, from boats, 21 Clamps, spar, 10, 54 Cloth, emery, 52 Commanding officer of vessel to be furnished with plan of wires, 52 Condition of firing-batteries, how to test, 28, 29 Connection to terminal, machine, or battery not to be made until, 20, 21 Contact, fire on, when using circuit-closer, Pattern B, 24 ” spar leading-wires, Pattern B. (See Wires). ” torpedo. (See Torpedo). Continuity of wires, testing, 32, 38 Crutch, swivel, 8, 54 Cutting plyers, 52

Depth. (See Immersion). Detonator, 10, 41, 42, 53 ” blocks, 10, 53 ” bridge, resistance of, 11 ” care of, 41 ” charge, 11, 42 ” dummy, 12, 53 ” packing and stowage, 10, 42 ” splice-sample, 53 ” splicing on, 18 ” testing, manner of, 17 ” when tested, to be put in safe place, 17 Diaphragms, rubber, 56 Distance, proper, for contact torpedo before firing, 21 ” ” ” exercise ” ” ” 22 ” ” ” service ” ” ” 21 Drier, steam, 13, 46, 56 Dry primers. (See Primer). Drying apparatus, gun-cotton, 13, 47, 48, 49 ” gun-cotton, rules for, 45 Dummy detonators, 12, 53 ” gunpowder fuze, 53 Dynamo-electric machine, pattern A, 32, 52 ” ” ” ” C, 36, 53

Earth-plates, 52 Electric switches, 15, 56 ” ” and permanent wires, use of, 25 ” ” not issued with permanent firing apparatus, 15 ” ” ” to be used as firing keys, 26 Emery cloth, 52 Exercise torpedo. (See Torpedo).

Fasteners, paper, 53 Fire at will, contact torpedoes, 24 ” on contact, contact torpedoes, 24 ” torpedoes using A machine and firing-key, 21 ” ” ” C ” , 21 ” ” ” battery and hand-firing key, 21 Firing-batteries, 27 ” ” boats, 28, 55 ” ” how to test condition of, 28, 30 ” ” management and care of, 29 ” ” no connection to be made with until, 20, 21 ” ” not to be used to test the circuit, 21 ” ” number furnished, 27 ” ” ships, 28, 55 Firing-key, D. E. machine, pattern A, 34, 52 ” ” ” ” ” ” to test, 36 Fittings, boats. (See Boat-fittings). ” bow, 8 ” heel, ship‘s torpedo spar, 16 ” ” ” ” ” substitute for, 16 ” ship‘s spar, 16, 56 Forward guy, ship‘s torpedo spar, how fitted, 16 Fuze bridges, spare, 55 ” gunpowder, dummy, 53 ” ” splicing on, 25 Fuzes, gunpowder, 12, 53 Fuzing torpedoes. (See Torpedo).

Glass jars for dry primers, 12, 41, 53 Gun-cotton, amount in torpedo outfit, 40 ” ” ” of water in when wet, 44 ” ” apparatus for drying, 13, 57, 48, 49 ” ” articles for testing. (See Chemical box). ” ” care of, 41 ” ” dry, packing and stowage of, 39 ” ” inspection of, 42 ” ” ” ” precautions to be taken, 44 ” ” magazine, 41 ” ” miscellaneous data, 49 ” ” primers. (See Primers). ” ” rules for drying, 45 ” ” test of. (See Inspection of gun-cotton). ” ” removed in priming, where placed, 17, 22 ” ” wet, packing and stowage of, 39 Gunpowder fuze, dummy, 53 ” ” splicing on, 25 ” fuzes, 12, 53 ” igniters, 11, 53 ” torpedoes, improvised, 24 Guy, after, ship‘s torpedo spar, 16 ” forward, ” ” ” how fitted, 16

Hand-firing key, 31, 55 Heel fittings, ship‘s torpedo spar, description, 16 ” ” ” ” ” substitute for, 16 Hemp twine, 52 Horizontal distance. (See Distance).

Igniters, gunpowder, 12, 53 Immersion, proper for the exercise torpedo, 22 ” ” ” ” service torpedo, 21 ” ” ” ” contact torpedo, 21 Improvised torpedoes, gunpowder, 24 Inspection of gun-cotton, 42 ” ” ” precautions to be taken, 44 Inspectors of ordnance at Navy Yard, duties of, 51 Instructions, Torpedo, copies of, 56 Insulated cable. (See Reel box). Insulating splices, 38 Insulation of wires, 37 ” ” ” not to be damaged, 37 ” ” ” testing the, 32

Jars, glass, for dry primers, 12, 41, 53

Key for ship‘s secondary spar, 5, 53 ” hand-firing, 31, 55 Knives, 3

Lead-covered wires, 14 Leading-wires. (See Wires). Lift, topping, ship‘s torpedo spar, how fitted, 16 Lines, reeving, 20, 53 ” ” weights, 20, 53 Locker, battery, 51

Machine connecting wires, 6, 7, 52, 53, 54 ” dynamo-electric, pattern A, 32, 52 ” ” ” ” C, 36,53 ” no connection to be made with until torpedo is immersed, 20, 21 Magazine, gun-cotton, 41 Magneto, testing, 31, 32, 55 Management and care of firing-batteries, 29 Monkey wrench, 52

Navy Yard, articles of torpedo outfit supplied at, 14, 56 ” ” Inspectors of ordnance at, duties of, 51 No connection to be made to terminal, battery, or machine until, 20, 21

Officer commanding vessel to be furnished with plan of wires, 52 Okonite tape, 18, 52 Open-end wrench, 52 Outfit, spar-torpedo, amount of gun-cotton in, 40 ” ” articles of, invoice number of boxes containing, 57 ” ” ” ” list of, 52 ” ” ” ” place of stowage, 57 ” ” ” ” spaced occupied when boxed, 57 ” ” ” ” supplied at Navy Yards, 14, 56 ” ” ” ” from Torpedo Station, 48 ” ” ” ” weight of when boxed, 57 ” ” how designated, 1 ” ” includes, 1

Packing, spherical rubber, 3, 53, 56 Paper fasteners, 53 Permanent wires, 14, 56 ” ” plan to be furnished to, 52 ” ” use of, 25 Pins, safety, for circuit-closer, spare, 53 ” ” ” ” ” to be in before priming, 23 ” torpedo, 5, 55 ” ” spare, 55 Plate, testing and firing, 53, 56 Plates, earth, 52 Plyers, cutting, 52 Precautions to be taken in inspection of gun-cotton, 44 Preparation of contact torpedo, 22 ” ” exercise ” pattern D, 22 ” ” service ” ” ”, 17 Primer blocks, 12, 39, 40, 41, 53 ” case, description of, 2 ” charge, 40, 41 ” not to remain long in exercise torpedo, 22 ” dry gun-cotton, care of, 41 ” ” ” ” how packed and stowed, 12, 39, 41 ” ” ” ” inspection of, 42 ” ” ” ” number furnished, 41, 42 ” ” ” ” precautions to be observed with, 42, 44 ” ” ” ” testing. (See Inspection of gun-cotton). ” wet ” ” how packed, 39 Priming the exercise torpedo, 22 ” ” service torpedo, 17 Priming, wet gun-cotton removed in, where stowed, 17, 22

Rectifier, 19, 52 Reel box, 6, 52 Reeving-lines, 20, 53 ” line weights, 20, 53 Resistance of detonator bridge, 11 Rivets for secondary spar butts, 54 ” ” ” ” caps, 54 Rubber diaphragms, 4, 56 ” packing, spherical, 3, 53, 56 ” tubing, 38, 52 ” washers, 2, 56 Rules for drying gun-cotton, 45

Safety-break of contact spar leading-wires, 6 ” ” to be kept open until, 24 Sample splice, 52 ” ” detonator, 53 Safety-pin circuit-closer, spare, 53 ” ” ” ” to be in before priming, 23 Screw-driver, 52 ” tap, 53 Screws for boat spar, pattern A, 53 Secondary spar. (See Spar). Service torpedo. (See Torpedo). Shipping contact torpedo, safety-pin to be in before, 23 ” secondary spar. (See Spar). ” torpedo. (See Torpedo). Ship‘s firing-batteries. (See Firing-batteries). ” testing circuit from, 20 ” torpedo spar. (See Spar). ” wire-box, 6, 53 Solution, alkaline, 45 Spar-bands, 8, 53 ” boat, pattern A, 10, 55 ” ” ” ” screws for, 53 ” ” ” ” to be taken apart when not in use, 10 ” clamps, 10, 54 ” leading-wires. (See Wires). ” secondary, butts, 5, 54 ” ” ” rivets, 54 ” ” caps, 5, 54 ” ” ” rivets, 54 ” ” keys, 5, 54 ” ” pattern A, description, 5 ” ” ” ” difference between boats and ships, 5 ” ” ” ” how packed for boats, 5, 54 ” ” ” ” ” ” ” ships, 5, 54 ” ” ” ” number supplied, 5 ” ” pattern A, shipping, 19 ” secondary, pattern A, toggles, 5, 53 ” ship‘s, description, 15 ” ” fittings, 16, 56 ” ” number supplied, 15 ” torpedo. (See Torpedo). Spare articles, 1, 14 Spherical rubber packing, 56 Spindle for torpedo. (See Torpedo). Splice wire, insulating of, 38 ” ” sample, 52 ” detonator, sample, 53 ” towing strain on, how to prevent, 19 Splicing on detonator, 18 ” ” gunpowder fuze, 25 ” wires, 37 Spring for circuit-closer, spare, 53 Steam-drier, 13, 46, 56 Storeroom, torpedo, 51 Strain, towing on splices, how to prevent, 19 Stuffing-boxes, 3 Supply-box, 8, 52 Switches, electric. (See Electric switches). ” ” and permanent wires, use of, 25 Swivel-crutch, 8, 54

Table showing weight, space, and place of stowage of articles, 57 Tape, okonite, 18, 52 Terminals, 15 ” connection with not to be made until, 20 Test-circuit through circuit-closer, pattern B, how to, 22, 23 ” condition of firing-batteries, how to, 28, 30 Tester, battery, 28, 55 Test, gun-cotton. (See Inspection of gun-cotton). Testing and firing-plate, 53, 56 ” circuit-closer, pattern B, 22 ” circuit from boat, 21 ” ” ” ship, 20 ” continuity of wires, 32, 38 ” detonator circuit in contact torpedoes, 24 ” ” manner of, 17 ” ” when, put in a safe place, 17 ” gun-cotton, articles for. (See Chemical box). ” insulation of wires, 32 ” magneto, 31, 32, 55 Toggles, secondary spar, 5, 53 Topping lift, ship‘s spar, 16 Torpedo, contact, circuit-closer to be tested before priming, 22 ” ” fuzing, 23 ” ” no connection to be made until, 21 ” ” preparation of, 22 ” ” priming, 23 ” ” proper distance and immersion, 21 ” ” shipping, 23 ” ” safety-pin to be in, 23 ” ” splicing on detonator for, 23 ” ” testing circuit, 24 ” ” to fire at will, 24 ” ” ” ” on contact, 24 ” ” spar leading-wires, pattern B, 7, 22, 23, 24 ” exercise, pattern D, description, 2 ” ” ” ” fuzing, 22 ” ” ” ” necessary to be closed water-tight, 3, 22 ” ” ” ” no connection to be made until, 20, 21 ” ” ” ” number issued, 2, 40 ” ” ” ” outfit of, 40, 55 ” ” ” ” packed, 39 ” ” ” ” preparation of, 22 ” ” ” ” primer not to remain in long, 22 ” ” ” ” priming, 22 ” ” ” ” shipping, 22 ” ” ” ” spindle packed, 5, 55 ” ” ” ” splicing detonator on, 22 ” ” ” ” testing, 22 ” ” ” ” weight, empty, 3 ” ” ” ” of charge, 3 ” ” ” ” when issued filled with wet gun-cotton, 3, 39, 44 ” ” proper distance and immersion, 22 ” Instructions, copies of, 56 ” outfit. (See Outfit). ” no connection to terminal, battery, or machine to be made until, 20, 21 ” packing boxes, 39 ” pins. (See Pins). ” service and contact, proper distance and immersion, 21 ” ” pattern D, conversion of to contact torpedo, 2, 22 ” ” ” ” description, 1 ” ” ” ” firing, 21 ” ” ” ” fuzing, 19 ” ” ” ” necessary to be closed water-tight, 2 ” ” ” ” no connection to be made until, 20, 21 ” ” ” ” not advisable to prime long before using, 17 ” ” ” ” number issued, 1, 40 ” ” ” ” outfit, 40, 55 ” ” ” ” preparation of, 17 ” ” ” ” primer-case, 2 ” ” ” ” priming, 17 ” ” ” ” shipping, 19 ” ” ” ” splicing detonator on, 18 ” ” ” ” spindle, 2, 55 ” ” ” ” testing, 20, 21 ” ” ” ” weight, empty, 2 ” ” ” ” of charge 2 ” ” ” ” when issued filled with wet gun-cotton, 2, 39, 44 ” spars, ship‘s, 15 ” ” ” number of, 15 Torpedo Station, articles supplied from, 52 ” store-room, 51 Torpedoes, firing, using A machine and firing-key, 21 ” ” ” C ” 21 ” ” ” battery and hand-firing key, 21 ” gunpowder improvised, 24 ” how named, 1 ” ” packed and marked, 39 ” ” to be stowed on board ship, 39 ” intended use of, 1 ” when received on board, what to do with, 39 Towing strain on splices, how to prevent, 19 Tubing, rubber, 38, 52 Twine, hemp, 52

Use of permanent wires and electrical switches, 25 ” ” leading-wires with circuit-closer, pattern B, 22, 23, 24

Washers, rubber, 2, 56 Water, amount in wet gun-cotton, 44 ” caps. (See Stuffing-Boxes). Weights, reeving-line, 20, 53 Wet gun-cotton, amount of water in, 44 ” ” ” packing and stowage of, 39 ” ” ” removed in priming, where placed, 17, 22 ” primers. (See Primers). Will, to fire at, contact torpedo, using circuit-closer, pattern B, 24 Wire-box, boat‘s, 7, 54 ” ” ship‘s, 6, 7, 53 Wire, continuity of, testing the, 32, 38 ” insulation of, 37 ” ” ” not to be damaged, 37 ” ” ” testing the, 32 ” splice, insulating, 38 Wires, contact spar leading, pattern B, 7, 22, 23, 24 ” lead-covered, 14 ” machine connecting, 6, 7, 52, 53, 54 ” permanent. (See Permanent). ” ” plan of, to be furnished to, 52 ” spar leading, how marked, 7 ” ” ” boats, 7 ” ” ” ” to be led through spar, 20 Wires, spar leading, never to be connected to terminals, battery, or machine until, 20, 21 ” ” ” ship‘s, 6, 54 ” ” ” ” to be stopped to spar, 19 ” splicing, 37 Wrench, monkey, 52 Wrenches open-end, 52

PLATES.

=PLATE I.=

SERVICE TORPEDO.—PATTERN D.

_A_ barrel. _B_ lower head. _C_ upper ” _g_, _h_ splices between leading-wires and detonator-wires. _K_ handle. _l_ lugs for handle. _k_ ” ” spindle. _i_, _i_ screw-holes for attaching circuit-closer. _n_ screw-rib for screw-cover. _r_ projection on handle shipping into spindle. _t_ screw-bolts securing spindle to lugs. _H_ spindle. _L_ spar leading-wires. _M_ water-cap. _P_ primer-case. _O_ screw-cover. _w_ rubber washer. _G_ spherical rubber packing. _D_, _D_ dry gun-cotton primer. _x_ detonator. _Y_ wet charge.

[Illustration: PLATE I.]

=PLATE II.=

EXERCISE TORPEDO.—PATTERN D.

_c_ case. _d_ lower loop. _e_, _e_ loops for transportation thumb-screw and for spindle. _f_ throw-back hinge with thumb-screw. _H_ spindle. _O_ cover. _w_ rubber washer. _M_ water-cap. _G_ spherical rubber packing. _Y_, _Y_, _Y_, _Y_ wet charge. _D_, _D_, _D_, _D_ dry primer. _x_ detonator. _L_ spar leading-wires. _g_, _h_ splices between leading-wires and detonator-wires.

[Illustration: PLATE II.]

=PLATE III.=

CIRCUIT-CLOSER.—PATTERN B.—CONTACT TORPEDO.

_A_ hollow brass casting. _M_ water-cap. _G_ spherical rubber packing. _O_, _O_ feet for attaching circuit-closer to service torpedo, Pattern D. _B_ inner brass plunger. _C_ spiral spring. _N_ ebonite collar. _I_, _I_ binding-posts. _E_ contact-springs. _t_ screw-cover. _s_, _s_ contact arms. _K_ outer plunger. _l_ safety-pin. _V_ rubber diaphragm. _k_ friction-plate.

[Illustration: PLATE III.]

[Illustration]

=PLATE IV.=

SECONDARY SPARS.

FIG. 1, SHIP‘S.—PATTERN A.

_A_ main spar. _B_ secondary spar. _a_, _a_ spar-bands. _b_ key-way. _c_ key. _l_ hole for torpedo-pin. _m_ torpedo-pin.

[Illustration: PLATE IV.]

FIG. 2, BOAT‘S.—PATTERN A.

_R_ main spar. _H_ secondary spar. _i_ butt. _k_ cap. _g_ toggle. _l_ hole for torpedo-pin. _m_ torpedo-pin.

[Illustration]

=PLATE V.=

CONTACT SPAR LEADING-WIRES.—PATTERN B.

_B_ battery. _C_ contact torpedo. _x_ circuit-closer. _D_ contact spar leading-wires. _H_ hand-firing key. _S_ safety-break.

[Illustration: PLATE V.]

=PLATE VI.=

SPAR-TORPEDO BOAT-FITTINGS.—PATTERN B.

_S_ heel-rest. _H_ swivel-crutch. _R_ cross-beam. _D_ ” bearing, riveted to cross-beam and bolted through rail. _E_ elevating-arm. _m_ plate washer. _n_ nut on end of securing rod. _G_ guide-ring. _K_ gear on elevating-arm. _M_ worm. _N_ worm-shaft, forward length. _O_ ” ” after ” _X_ hook-coupling. _P_ elevating-wheel. _Q_ clutch. _L_ detaching-lever. _T_ torpedo. _A_ main spar. _B_ secondary spar.

[Illustration: PLATE VI.]

[Illustration]

=PLATE VII.=

JUNCTION OF TUBES FORMING BOAT‘S SPAR.—PATTERN A.

_A_ large tube. _B_ small tube. _c_, _c_ rings. _d_ shoulder. _e_ screw-holes. _f_ feather. _g_ score.

[Illustration: PLATE VII.]

[Illustration]

=PLATE VIII.=

FIG. 1, DETONATOR.

_A_ copper case. _B_ plug. _c_, _c_ detonator-legs. _D_ bridge. _F_ gun-cotton priming. _H_ fulminate of mercury.

FIG. 2, DETONATOR BLOCK.

_A_ block. _B_ ” cover. _C_, _C_ detonators. _D_, _D_ tin box.

[Illustration: PLATE VIII.

_Fig. 1._]

[Illustration: _Fig. 2._]

=PLATE IX.=

FIG. 1, PERMANENT WIRES.

_A_, _A_ electric switches (on bulwarks under bridge). _B_, _B_ forward terminals. _C_, _C_ after ” _D_, _D_ forward permanent wires. _E_, _E_ after ” ” _G_, _G_ permanent wires leading from bridge to lower binding-posts of electric switches. _H_, _H_ wires leading from bridge to common-return terminals, below switches. _K_ terminal on bridge for wires _H_, _H_. _L_, _L_ ” ” ” ” ” _G_, _G_. _X_ firing-battery connected to terminals on bridge.

FIG. 2, CONNECTIONS WITH FIRING-KEY OF “A” MACHINE.

_B_, _B_ terminals of firing-key. _T_, _T_ ” ” ” Key “_T_” test key. Key “_F_” firing key. _M_, _M_ wires to terminals _L_, _L_ on bridge. (Fig. 1.) _N_ wire to terminal _K_ on bridge (common return). (Fig. 1.) _O_, _O_ machine-connecting wires.

FIG. 3, CONNECTIONS WITH FIRING-BATTERY.

_B_, _B_ terminals of battery. _M_, _M_ wires to terminals _L_, _L_ on bridge. (Fig. 1.) _N_ wire to terminal _K_ on bridge (common return). (Fig. 1.) _H_ hand-firing key.

[Illustration: PLATE IX.

_Fig. 2._]

[Illustration: _Fig. 3._]

[Illustration: _Fig. 1._]

=PLATE X.=

FIG. 1, ELECTRIC SWITCH.

_A_ permanent wire to forward torpedo. _B_ ” ” ” after ” _C_, _C_ ” ” common return. _D_ wire to battery or firing-key of machine. _E_ commutator of switch.

[Illustration: PLATE X. _Fig. 1._]

FIG. 2, TERMINAL.

_H_ binding-screw. _I_ permanent wire. _w_ wire temporarily connected.

[Illustration: _Fig. 2._]

=PLATE XI.=

HEEL FITTINGS FOR SHIP‘S SPAR.

_a_ ship‘s spar. _b_ thrust-plate (30″ diameter). _c_ eye-bolt through thrust-plate and ship‘s side. _d_ heel-bolt.

[Illustration: PLATE XI.

_Fig. 2._]

[Illustration: _Fig. 1._]

=PLATE XII.=

SHIP’S SPAR FITTINGS.

_a_ ship’s spar. _b_ topping lift. _c_ forward guy. _d_ after ” _e_ span for topping lift (16′ long). _f_ ” ” forward guy (16′ long). _x_, _x_, _x_, _x_ bands on spar (5′ apart).

[Illustration: PLATE XII.]

=PLATE XIII.=

BATTERY CELL.

_a_ okonite jar. _b_, _b_ zinc cylinder. _c_ platinum plate. _d_ muslin bag filled with crushed carbon. _e_ ebonite disc. _f_ ” plug. _g_ sal-ammoniac solution. _h_ positive terminal. _i_ negative ” _k_ rubber cover. _r_ rubber ring.

[Illustration: PLATE XIII.]

=PLATE XIV.=

BATTERY TESTER.

_a_, _a_ battery terminals. _b_ ” tester. _c_ fuze-bridge in tester.

[Illustration: PLATE XIV.]

=PLATE XV.=

FIG. 1, HAND-FIRING KEY.—PATTERN B.

_a_, _a_ hickory pieces. _c_, _c_ contact studs. _L_, _L_ leading-wires. _d_ rubber cot. _e_ safety-pin with hole for laniard. _f_ eye-bolt for laniard.

FIG. 2, DIAGRAM SHOWING HAND-FIRING KEY IN CIRCUIT.

_B_ battery. _H_ hand-firing key. _w_, _w_ leading-wires.

[Illustration: PLATE XV.]

=PLATE XVI.=

FIG. 1, “A” MACHINE AND FIRING-KEY CONNECTED.

_A_ “A” machine. _C_ firing-key. _B_, _B_ terminals of firing-key. _T_, _T_ ” ” ” Key “T” test key. ” “F” firing-key. _O_ machine-connecting wires. _w_, _w_ wires to torpedo.

FIG. 2, “C” MACHINE CONNECTED.

_D_ “C” machine. _C_ firing-key (in the machine). Key “T” test key. ” “F” firing-key. _w_, _w_ wires to torpedo.

[Illustration: PLATE XVI.]

=PLATE XVII.=

FIG. 1, firing-key, short-circuit. ” 2, ” testing circuit. ” 3, ” firing-circuit. _O_, _O_ machine-connecting wires. _w_, _w_ wires to torpedo. _B_, _B_ terminals of firing-key. _T_, _T_ ” ” ” Key “T” test key. Key “F” firing-key.

[Illustration: PLATE XVII.

_Fig. 1._]

[Illustration: _Fig. 2._]

[Illustration: _Fig. 3._]

=PLATE XVIII.=

STEAM-DRIER.

[Illustration: PLATE XVIII.

_Fig. 1._]

[Illustration: _Fig. 2._]