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differences in detail. The contract was awarded November 15, 1887, and the machinery is to be completed May 15, 1889.

The cylinders and linings have been cast, and the latter secured in place; the cylinder covers, valves, and valve liners have been cast, and work on them is well advanced; the connecting-rods and tie-rods are forged and nearly completed; the crankpin and crank-shaft brasses have been cast, and some of them lined with white metal; the thrust and line shaft bearings, and the injection and outboard delivery valves are completed; the stern tube bushings have been cast, and are being planed; the reversing engines are nearly completed; the bed-plates have been cast, and one set of engines is in course of erection in the shop; the details of valve gear are well advanced, and about one-half of the shafting is being turned and bored. Material for the boilers has been received, and the work is in a forward state.

BENNINGTON (Gunboat No. 4).—Machinery is a duplicate of that of the Concord. The state of work on the engines is the same as for the Concord. Two of the boilers are nearly completed, two more are well advanced, and the plates for the others are being bent, planed, and drilled.

The state of work on the machinery of the vessels reported upon in my last annual report is as follows:

CHARLESTON (Cruiser No. 2).-The work on the engines of this vessel is practically completed in the shop, and they are now in course of erection on board. Four of the main boilers are completed, and are in the ship; the other two require only the longitudinal braces for completion. The auxiliary boiler and the uptakes and furnace fronts of the main boilers are nearly completed, and work has been started on the smoke-pipe. The contractors report that the vessel will be ready for trial in December.

The following changes in design, in addition to those enumerated in my last annual report, have been proposed by the contractors and approved:

Spacing of boiler tubes slightly reduced in order to get in the required number of tubes.

Number of wildcats on windlass reduced from four to two.

Thrust rings of phosphor bronze instead of composition; spare set of composition. Eccentric straps and levers of forged instead of cast steel.

Piston-valve packing rings reduced in width, and steel substituted for cast-iron and Perkins's metal.

Tobin's metal bolts made with a smaller percentage of tin than specified, in order to facilitate working.

Vertical braces of combustion chambers enlarged at eye, and bolts and nuts substituted for split pins.

Staying of low-pressure steam-ports changed from ribs to screw-stays.
Cylinder and pipe lagging to be teak instead of black walnut.

Auxiliary condenser, evaporator, and forced draft appliances for auxiliary boiler added on account of auxiliary boiler being too small for its work. Furnace of auxiliary boiler strengthened by an Adamson ring.

Steam and reversing valves of steam windlass to be slide instead of piston valves. Entirely new design of air-pumps after those of the original design had been nearly completed. This change was necessary on account of the small capacity of the pump in the original design, and the reports of the poor performance of the air-pumps of vessels fitted with machinery built from the same designs, the contractors expressing doubt about being able to maintain the required vacuum. In the new design a double-acting plunger is substituted for a single-acting bucket plunger. Engines to be bedded on cast-iron instead of on wood.

Change in method of securing boilers in ship on account of saddles being too large for boilers.

Condensers to be clothed with non-conducting material.

BALTIMORE (Cruiser No. 3).-The propeller shafts, outboard delivery and injection valves, main circulating pumps and engines, fire and bilge pumps, main and auxiliary feed pumps, auxiliary air and circulating pumps and engines, and auxiliary condenser, are finished and in place on board ship. The crank, thrust and intermediate shafts, line-shaft pillow-blocks, and condensers are finished and ready to go in place. The main and auxiliary boilers are ready for testing, and the uptakes and furnace fronts are well advanced. The cylinders, engine framing, crank-shaft pillow-blocks, and diagonal stays are completed and erected in the shop, the valve faces in place, and crank-shaft brasses ready for boring. The pistons and rods are nearly completed, and the air-pumps ready for erecting. Work on the connecting rods, valves, and valve gear, reversing engines and gear, and thrust bearings, is well advanced.

The following changes in design, in addition to those enumerated in my last annual report, have been proposed by the contractors and ap proved:

Crosshead slippers made in two pieces, and bearing-surface increased.

Condenser tube sheets changed from one plate of composition to two of Muntz metal united by scarph joint, on account of difficulty of getting a good casting. Capstan stepped from one end of windlass bed instead of near center.

Details of crank-shaft pillow-block frames (cast steel) changed to facilitate casting, the third attempt having proved a failure.

Position of outboard delivery valve changed in order to clear a butt strap on outer plating.

Air-pump piston rods of Muntz metal instead of naval brass.

New design of thrust block provided with means of water circulation.

Changes in feed tank made necessary by the introduction of gussets on ship's side to strengthen hull.

Slight change in one low-pressure valve-chest to correct error in casting.

Two additional holes cut in caps of low-pressure crank-shaft pillow-blocks to correct error and agree with holes in brasses.

Low-pressure valve-chest covers of cast-iron instead of cast-steel, on account of impossibility of getting sound castings.

YORKTOWN (Gun-boat No. 1)-The engines, boilers, and auxiliary machinery, with the exception of a few details, are completed and erected on board, but the boilers have not yet been clothed. Preliminary dock trials have been made.

The following changes in design, in addition to those enumerated in my last annual report, have been proposed by the contractors and ap proved:

Smoke-pipe to have a double instead of a single shell, dampers at bottom of uptake instead of near top, and pipe to be divided into two parts instead of four above dampers.

One low-pressure valve-motion rock-shaft of wrought iron instead of cast-steel, on account of difficulty of getting good castings.

Combined check and stop-valves on boilers instead of two separate checks. Cylinder-heads to be of cast-iron, as originally specified, instead of cast-steel, as

allowed.

PETREL (Gun-boat No. 2).-The engines, with the exception of a few minor details, are practically completed, and are being erected in the shop. The boilers and smokepipe are completed, and work on the uptakes and pipes is progressing favorably. The propeller shaft, stern-tube, and stuffing-box, and the sea valves are finished and in place on board.

The following changes in design, proposed by the contractors, have been approved:

Furnaces made in two lengths, welded, instead of in one.

Hand-wheel of main stop-valve of composition instead of wrought iron.
Air-pump barrel cast separate from casing.

Screw propeller of aluminum bronze instead of manganese bronze.
Change in method of fitting boiler braces.

VESUVIUS.-The machinery is in place on board, and has been tried by the con

tractors.

MONADNOCK.-New machinery for this vessel has been designed by the Bureau, material advertised for, and work commenced at the Mare Island navy-yard. The design is for twin-screw, horizontal, triple-expansion engines of 3,000 I. H. P., each engine, and each pair of boilers being in a separate water-tight compartment. Cylinders 194, 304, and 524 inches diameter by 30 inches stroke; piston valves worked by Stephenson link-motion; steel crank-shafts, each made in interchangeable sections; cylindrical sheet-brass condensers, each with 2,485 square feet of condensing surface; independent horizontal air-pumps, and centrifugal circulating pumps. Four cylin drical return-tubular boilers, each with two 46-inch furnaces; diameter of boilers, 12 feet 2 inches; length, 10 feet 1 inch; total grate surface, 200 square feet; total heating surface, 6,242 square feet; closed ash-pit system of forced draft; steam pressure. 160 pounds; weight of machinery, including water in boilers and condensers, 354 tons. The stern tubes and propeller-shafts as originally designed being in place, the new design was somewhat restricted in order to preserve the same shaft lines.

The old design of machinery for this vessel was for inclined two-cylinder compound

engines of 1,600 I. H. P., both engines being in the same compartment, and all the boilers in one compartment; weight of machinery, including water in boilers and condensers, 547 tons.

Thus, by the use of higher pressure, increased piston speed, forced draft, and better materials, there has been a saving in weight of 193 tons, and also a saving in space occupied by the boilers, there being only four in the new design, while in the old one there were six of the same size; besides which the horse-power has been increased from 1,600 to 3,000, which will increase the speed of the ship at least two knots. The saving in weight and the reduction of the number of boilers will allow an increase either in the amount of coal carried, or a corresponding increase in armament or ammunition.

TERROR.-The machinery has been tested and accepted. The principal work remaining to complete the machinery is the turret-turning gear, and covering the boilers. The boiler covering was omitted, owing to the probability of its rotting while the vessel is laid up awaiting her turrets, armor, and guns.

AMPHITRITE. The machinery has been tested, but owing to the intense heat of the fire-rooms, due to the boiler clothing having been omitted for the same reason as in the Terror, the trial had to be discontinued after sixteen hours' duration.

NAVY-YARDS.

The work of the Bureau in the navy-yards during the past year has consisted principally in repairs to existing machinery of naval vessels, and putting in boilers already built. The only yard where new machinery is building is that at Mare Island, where the machinery for the Monadnock has been begun.

In order to be prepared for any emergency, when the navy-yards would be called upon to build machinery rapidly, I would recommend additions to the shop buildings and tools as noted below in detail.

The machinery most needed at navy-yards to bring them up to modern requirements is in the way of boiler-making plant, capable of dealing with the heavy plates required by high steam pressures.

I would renew my recommendation of last year that a large proving and testing machine be built at the New York yard, with appliances for proving all parts which enter into marine engines, including crankshafts. A similar machine should also be erected at Mare Island, Cal., as there is no such machine on the Pacific coast.

I would also renew my recommendation that a central steam-generating plant be started in each principal navy-yard, and gradually added to, as the present boilers, scattered in various parts of the yard, become unfit for use.

From this centralstation steam could be conducted to the various points where large powers are needed, and electricity to places where small motors are wanted. The dynamos of this station could also be used for lighting the yard and the dark parts of vessels undergoing repairs. It would be found that the running expenses would be thus greatly reduced and danger from fire much diminished. I would recommend that $20,000 be appropriated to begin such central stations at each of the navy-yards at New York, Portsmouth, Norfolk, and Mare Island. A synopsis of the principal work done at the various navy-yards, together with an account of the expenditures at each yard, other than for work done on naval vessels, will be found below. A list of machine tools which I would recommend to be added during the coming year is also given, with an estimate of cost.

NEW YORK NAVY-YARD.

At this yard during the last fiscal year work in the way of preservation, overhauling, and repairs was done on the machinery of the Alarm,

Atlanta, Boston, Despatch, Dolphin, Catalpa, Chicago, Cohasset, Enterprise, Fortune, Galena, Intrepid, Leyden, Minnesota, Miantonomoh, Nantucket, Nipsic, Nina, Ossipee, Portsmouth, Pensacola, Richmond, Trenton, and Vermont, as elsewhere noted in connection with these vessels.

Work was done on machinery and stores and shipped to the following vessels: Brooklyn, Kearsarge, Marion, Omaha, Tallapoosa, and Wabash. A number of steam-launches were overhauled and repaired. The work done for the other Bureaus was briefly as follows: Ordnance.-Pipe work on training-engines of the Boston, pipe work on search-light dynamo engine and steam-launch dynamo of the Chicago. Yards and Docks.-Made castings for derrick; repaired derrick-engine; tubed boiler and cast hammer and winches for pile-driver; repaired boiler and made new connections; repaired old and made new exhaust-pipe; refitted piston, repaired smoke-pipe, straightened airpump piston-rod, cast grate-bars, and made minor repairs on pumping machinery of the dry-dock; made miscellaneous castings for iron der ricks for dry dock; repaired boiler in dry-dock stone-shed; repaired hoisting engine boiler.

Narigation.-Made various castings, and making deck-plates for bin nacles and sounding-machines; made changes in piping of dynamo engine of the Atlanta, Boston, and Trenton; made all connections to dynamo engines of the Chicago.

Equipment and Recruiting.-Galley work for the Jamestown; making turnbuckles; repairing canvas-testing machine; repairing boilers and engine; completing boiler for cob-dock.

Medicine and Surgery.-Repairs to two boilers at the naval hospital. Provisions and Clothing.-Repairs to engines, boilers, and feed-water heater.

Construction and Repair.-Made various articles of cast-iron and com position, such as stanchions, cleats, shoe for forefoot of the Nipsic, man-hole plates for the double bottom of the Atlanta, castings for the steering-gear of the Dolphin, pinions and wheels, scupper drips, expanding tubes in boiler, repairs to shop-boilers, normans for the Boston, hawse-pipe covers, sheaves, tracks for guns, blue print frame, railings, grate bars, clamping bars for Hotchkiss towers of the Boston, and anchors for lifebuoys. Use of floating derricks for hoisting boats and various other purposes. Made three boilers for new shops.

The following machine-tools were added to the Bureau's shops during the year:

One testing-machine.

One plate-planing machine.

One riveting-machine.

One shearing-machine.

One set flange-blocks.

One flange punch.

Twelve rivet-forges.

One leather-shaving machine.

The lathes, planers, slotters, and other tools in the machine, patteru, boiler, and copper shops were thoroughly overhauled. The cranes in the foundry were taken apart, cleaned, and repaired where needed.

The machine-shop at this yard is not adapted to the proper handling of heavy work or to the erecting of large engines without loss of time. The original plan of the shop included a wing for the heavier machinetools, and to be used as an erecting-shop. This wing should be built and fitted with large overhead traveling cranes. An erecting floor

should be built and the heavier machine-tools moved out of the present shop to make room for the tools that are needed there.

I would recommend that an appropriation be asked for to purchase the following tools, in order to put the shop in condition to handle work more rapidly and with greater economy than at present:

One vertical boring, turning, and facing machine....

One screw-cutting lathe, 72 inches swing and 50 feet centers

Two lathes, 17 inches swing

Two lathes, 20 inches swing..

Two lathes, 263 inches swing..
Que surface-grinding machine.
One tool-grinder.....

One shaft-straightening machine..

One hydraulic flanging-machine........
One accumulator ...

One hydraulic pressure-pump

One hydraulic bending-press for heavy boiler-plates

One boiler-shell drilling-machine

$25,000.00

7,600.00

1,700.00

2,250.00

3,050.00

800.00

300.00

1,000.00

5,500.00

1,600.00

1,000.00

10,000.00

1,500.00

One overhead traveling crane for new boiler-shop.

20,000.00

One 600-ton proving and testing machine....

30,000.00

One overhead traveling crane for the foundry.
Cost of setting the above machines, foundations, pipes, etc., and line-
shafting for the new boiler-shop.....

20,000.00

25,000.00

Total.......

156, 300.00

The expenditures of the Bureau at this yard, other than those for work done on the machinery of naval vessels, are as follows:

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Care and repair of and additions to shop tools

Running and firing yard engines and boilers, and repairs to same.

Repairs and maintenance of yard steam-launches and ferry

Repairs to old derrick.

$5,495.55 879.68 5,860. 19 53,845.54

8,712.78

2,032.70

1,894.32

34, 941.30

4,545.92

Completing new floating derrick.

[blocks in formation]

5,677.28

1,955, 02 1,025.08 294.63 2,967.32

848.86

122.50

5, 304.65

3, 374.37

2,583.04

3,254.64

145, 615. 37

PORTSMOUTH NAVY-YARD.

During the last fiscal year the repairs on the boilers and machinery of the Swatara were completed, and minor repairs made on the machinery of the Ossipee. Completed the repairs to the machinery and boilers of the Kearsarge, new boilers having been fitted and the Nantasket's engines thoroughly overhauled, erected on board, and new steam-pipes and heaters fitted.

Building machinery for ferry launch for training station. Repairs were made on the machinery and boilers of the Leyden and Emerald. Work was done for other Bureaus as follows:

Yards and Docks.-Made small castings, such as grate-bars, gasretorts, etc.

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