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APPENDIXES

TO THE

REPORT OF THE CHIEF OF ENGINEERS,

UNITED STATES ARMY.

FORTIFICATIONS, ETC.

APPENDIX No. I.

GUN AND MORTAR BATTERIES-TORPEDO SAED, NEW YORK HARBOR.

REPORT OF LIEUT. COL. GEORGE L. GILLESPIE, CORPS OF ENGINEERS, OFFICER IN CHARGE, FOR THE FISCAL YEAR ENDING JUNE 30, 1893.

IMPROVEMENTS.

4. Mortar battery.
b. Gun-lift battery.

c. Torpedo shed.

ENGINEER OFFICE, U. S. ARMY,

New York, N. Y., July 8, 1893. GENERAL: I have the honor to transmit herewith annual reports, in duplicate, for the fiscal year ending June 30, 1893, upon fortifications in my charge. Very respectfully, your obedient servant,

G. L. GILLESPIE,

Lieut. Col., Corps of Engineers. Brig. Gen. THOMAS L. CASEY, Chief of Engineers, U. S. A.

GUN AND MORTAR BATTERIES.

Plans have been prepared for the new works of defense, and during the fiscal year operations were carried on upon the construction of Mortar Battery No. 1, with ditch defense, arranged for sixteen 12-inch breech-loading rifled mortars, and upon one 12-inch gun battery, with lıydraulic lifts for two 12-inch, breech-loading, high-power steel rifles, of which mention was made in the last annual report.

I A.

MORTAR BATTERY No. 1.

The mortar battery was begun in November, 1890, under instruc. tions from the Chief of Engineers dated August 6 and September 13, 1890, in accordance with plans of The Board of Engineers dated September 28, 1888.

From the appropriation made by act of Congress approved August 18, 1890, for gun and mortar batteries, an allotment of $201,000 was made for its construction, and on February 24, 1893, a further allotment of $33,000 was made from the appropriation for gun and mortar batteries, act of July 23, 1892, to be applied to the completion of this mortar battery.

On March 10, 1893, an allotment of $20,000 was made from the appropriation, act of February 18, 1893, for "gun and mortar batteries, for the construction of gun and mortar platforms,” “to be applied to the construction of eight mortar platforms.” At the close of the last fiscal year the condition of the work was as follows:

The concrete masonry of the battery was completed, excepting the floors of the magazines and passages, the sloping concrete surface capping of the retaining walls of the mortar pits and designed to protect the slopes from the effects of blast, the counterscarp wall, and galleries. The line of the ditch had been cleared of undergrowth and stumps and graded ready for the foundations of the counterscarp wall, and 13,025 cubic yards of concrete had been put in place.

At the close of the last fiscal year two contracts were in force:

1. With the Lawrence Cement Company, dated December 29, 1890 (expired January 1, 1892, extended to August 1, 1892), approved by the Chief of Engineers January 12, 1891, for the delivery of 30,000 barrels of cement, at $1.02 per barrel. Completed July 25, 1892.

2. With John A. Bouker, dated December 29, 1890 (expired January 1, 1892, extended to November 1, 1892), approved by the Chief of Engineers January 8, 1881, for the delivery of 21,000 cubic yards of broken granite, at $1.63 per cubic yard. Completed July 29, 1892.

Under sealed proposals opened July 20, 1892, a contract was made July 22, 1892, with Calvin Tomkins, of New York, the lowest responsible bidder, for the delivery of 25,000 barrels "Old Newark” Rosendale cement, at $0.939 per barrel, and 20,000 cubic yards of broken stone, at $1.284 per cubic yard.

There have been delivered under this agreement, up to June 30, 1893, 12,102 cubic yards of broken stone and 23,410 barrels of cement, of which amounts 10,000 cubic yards of broken stone and 19,773 barrels of cement were applied to the construction of masonry at the mortar battery.

Under sealed proposals opened April 12, 1893, bids for furnishing certain material for the construction of mortar platforms were accepted as follows:

WALDO & STOUT, BRIDGEPORT, CONN.

192 aluminium bronze bolts, at 297 cents per pound.
192 phosphor-bronze washers, at 224 cents per pound.
192 steel nuts (for above bolts), at 577 cents each.

128 wrought-iron anchor bolts, with hexagonal nuts, at 39 cents each. The aggregate cost of the above bolts and nuts for eight platforms is $3,742.80.

CASEY & SHERWOOD, NEW YORK CITY,

For eight sets of eight stones each, or 1,063 cubic feet granite rings (which

form the upper surface of the mortar platforms and the seat of the base ring of the mortar carriage), at $319 for one set, equivalent to $2.4007 per cubio

foot. All of the above material is to be delivered on or before July 15, 1893.

The construction of masonry was continued throughout the year, excepting from December 1, 1892, to May 1, 1893, during which time it was necessarily suspended on account of cold weather.

The counterscarp wall (2,200 feet in length) and galleries are completed, excepting about 140 feet of the wall where openings have been left for construction purposes. The floors in the magazines and main galleries are laid within 4 inches of their finished level and the concrete protection for the slopes in the mortar pits is nearly finished.

The total masonry constructed during the year was 13,827 cubic yards and from the beginning 26,852 cubic yards. The average cost per cubic yard for all was $5.20.

The work of filling sand in the embankments covering the magazines and passage ways and surrounding the mortar pits has been carried on continuously since September 12, 1892, and at the close of the fiscal year 118,478 cubic yards had been excavated, hauled, and deposited, completing the sand cover inside the ditch, excepting about 5,000 cubic yards. This, with 9,449 cubic yards reported last year, makes a total of 127,927 cubic yards to June 30, 1893.

The progress sheet forwarded herewith (Pl. 1*) shows the total masonry constructed to June 30, 1893; also, in detail, that for each month of the fiscal year. The same drawing shows the embankment to date.

The total estimated amount of sand filling inside the ditch is 125,184 cubic yards; the amount in place June 30, 1893, was 127,927 cubic yards, an excess over the quantity estimated of 2,743 cubic yards. This excess is not due to an error in the estimate, and is easily accounted for. The sand at the battery site is dry and shifting; high winds frequently prevail, during which sand deposited on the higher portions of the embankments is blown away and again deposited in the ditch and upon those slopes not exposed to the wind. This will be checked when the sod which is to cover the upper and more exposed parts of the slopes is in place, and the surplus sand can all be utilized economically in filling in the covering of sand exterior to and resting against the counterscarp wall. Experiments made during the year indicate that the long slopes adjoining the ditch can be successfully and economic

* Omitted.

ally protected from wind and weather by planting thereon a kind of heath, native to the locality, which is found in situations quite as exposed, both to sun and wind, as are the slopes mentioned above.

The following tables show in detail the cost of the operations during the year, the plant in use, and the average daily number of employés of each class:

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NOTE.-The first cost of cement and concrete stone for the year, in the above table, is obtained by combining the prices under the contracts of the Lawrence Cement Company (terminated July 25, 1892) and Calvin Tomking for cement, and those of Johu A, Bouker (terminated July 29, 1892) and Calvin Tompkins for coucrete stone, as follows:

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II. COST OF MATERIAL AND MANUFACTURE OF ONE CUBIC YARD OF CONCRETE.

Composition: 1 cement, 2 sand, 5 broken stone.

NOTE.—One charge of the mixer is equal to 1.05 cubic yards of masonry, machine mixed and deposited by derrick.

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