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The approved project for the defense of this harbor contemplates, for the present, an armament of twelve 12-inch guns on lifts, fifteen 10inch and five 8-inch guns on disappearing carriages, one hundred and twenty-eight 12-inch mortars, and submarine mines to be operated from four mining casemates.

During the year the concrete masonry of one 10-inch gun position has been completed on an average to the crown of the arches forming the service magazine and shell room. In the two other gun emplacements operations have been confined to the demolition of old masonry, the removal of earth embankments, and the preparation of foundations for the new masonry. Large quantities of concrete material are being collected.

The entire excavation for the masonry of the mortar battery was completed, and in doing this about 8,000 cubic yards of gravel for concrete was obtained and 9,000 cubic yards of embankment built; 6,700 cubic yards of concrete was put in place, thus completing the masonry of the two rear pit walls, the intervening chambers, the central magazines, and connecting passages.

New York Harbor, New York.-Officers of the Corps of Engineers in charge: Col. D. C. Houston, Lieut. Col. G. L. Gillespie, with First Lieut. Harry Taylor under his immediate orders until August 12, 1891, and First Lieut. James G. Warren since that date, and Lieut. Col. W. R. King.

The projects for the defenses of both the southern and eastern entrances to this harbor contemplate, for the present, an armament of nineteen 12-inch guns on lifts, seventeen 10-inch and nine 8-inch guns on disappearing carriages, one hundred and seventy-six 12-inch mortars, and submarine mines operated from five mining casemates.

Colonel Houston reports as to the three emplacements for 8-inch guns, that about 7,600 cubic yards of earth has been excavated and placed in embankment, 8,485 cubic yards of concrete has been made and placed, stone has been cut out and set for magazine-door fittings, and the construction of doors commenced.

The concrete cover of magazines and guns of two positions has been practically completed except a section in front of the pintles, left vacant temporarily. The concrete work of the third position is about one-third completed, and the earth work in front of the concrete of the third position is over half built.

Increased storage and wharfage have been provided.

Relative to the construction of the gun battery for two 12-inch guns and one mortar battery, Lieutenant Colonel Gillespie reports:

The construction of the concrete masonry for the gun-lift battery was continued throughout the year, except when suspended from December 23, 1891, to April 13, 1892, on account of cold weather.

At thé close of the fiscal year the masonry of the battery had been carried to an average height of 32 feet above the bed of the foundations, to reference (39.0); the sand core between the exterior 20-foot wall and the interior 10-foot wall had been filled and compacted. The settlement was done by use of water and averaged about 15 per cent.

The total amount of masonry constructed during the year was 29,875.5 cubic yards; that previously reported was 3,055 cubic yards, making the total to June 30, 1892, 32,930.5 cubic yards. There remain to be constructed 10,167.5 cubic yards of masonry; 76 per cent of the masonry construction is therefore completed.

The masonry consists of 23,815 cubic yards of concrete, mixed and placed, at $4.13 per cubic yard, and 5,512 cubie yards of large stone, delivered and placed, at $3.31 per cubic yard, the average cost of the

two combined during the year, being $3.91, and the average cost of all the masonry laid, from the beginning, being $5.51, inclusive of superintendence, purchase and maintenance of plant, repairs to buildings, office expenses, and general work.

The contract for the mechanism of the northwest lift was practically completed June 30, 1892, at which date all the parts of the mechanism had been completed, delivered, and set in place, except the final adjustment of the ammunition lift and rammer. A test had been made of the connections to the accumulators, resulting in the satisfactory raising of the accumulators. The final test of the mechanism, with its ultimate load of gun and carriage, will be made in August.

The estimated total cost of a completed battery of this type, accommodating two guns, is $457,000 (not including cost of armament), of which $283,000 is applied to masonry and sand covering, and $174,000 to the mechanism of two gun lifts.

Special modifications of the original plans of the gun-lift battery have been approved, which provide for a defensible entrance and for additional security against attack by boat parties on front and flanks.

A building for office purposes was erected at a total cost of $1,548, and a frame building for the general use of the Engineer Department is in process of construction, by contract, at a cost of $5,000.

At the close of the fiscal year the concrete masonry of the mortar battery was completed, excepting the floors of the magazines and passages, the sloping concrete surface capping for restricting damages by blasts in the pits, the retaining walls, and the counterscarp wall and galleries.

The line of the ditch was cleared of undergrowth and stumps and graded ready for the foundation of the counterscarp wall.

There were constructed 13,025 cubic yards of concrete, at an average cost of $5.28 per cubic yard, including superintendence, purchase and maintenance of plant, repairs to buildings, and general work not capable of specification. No sand has been moved, except when required to prepare for laying of masonry. The total estimated cost of Die battery, without armament, is $200,000.

Concerning the construction of emplacements for two 10-inch and one 8-inch guns, Lieutenant Colonel King reports:

Steam hoisting engines and derricks have been placed upon the wharf so that two or even three boats may discharge their cargoes at the same time. A new winding engine has been placed at the head of the incline, of sufficient power to haul heavily loaded cars from the bottom to top in less than one minute, and a small locomotive has been built for handling them when they reach the upper level.

The work of preparing emplacements for two 10-inch and one 8-inch rifles has been continued during the year; one magazine and part of the parapet connecting it with the next emplacement have been completed, and the second magazine is well under way. The earth excavation and concrete work and receiving materials have been carried along together as circumstances would permit, and the daily output of concrete in place has in one case reached 160 cubic yards with a single mixer. This, however, is far above the average, as there are many delays in moving machinery, preparing centers, etc.

The entire quantities of work done on the battery during the year have been as follows, viz:

Cubic yards. Earth excavation

10, 897 Concrete in place

7, 676 Earth embaukwent

6, 346

As to the construction of a mortar battery Lieutenant Colonel King reports:

The buildings for storehouse, office, and blacksmith's shop were completed and derricks and steam drills were kept at work during the year when the weather would permit. Cars and track were bought, and a substantial wharf, with an incline connecting it with the battery, was completed.

A suitable stationary engine was procured and set up at the head of the incline for handling cement, sand, and other heavy materials that will be required in the construction of the battery.

The earth excavation for all the mortar pits and magazines and passages was completed, excepting a part of one mortar pit, and nearly all of this earth and some of the rock was placed in embankment where it will not have to be removed again.

The rock excavation, which is the most serious item of the work required, has also been pushed during the year, and nearly all that required to be removed from two mortar pits and all of the magazines and passageways has been removed and a third pit is partly excavated.

The condition of the work is now such that the concrete work can be commenced at once, and a stone crusher will be set at work at an early day to supply the broken stone. There is enough stone on the ground that has been taken from the pits to supply all the stone needed for concrete on the entire work, and it can be crushed for a mere fraction of what it would cost to buy the stone already broken.

The entire quantities of materials removed during the year are the following, viz: Rock blasted and removed

.cubic yards.. 3,917 Earth excavated and placed in embankment

3, 462 Track laid.

linear feet.. Drain laid

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370

500 Washington, District of Columbia.Officers of the Corps of Engineers in charge: Lieut. Col. Peter C. Hains, uutil November 23, 1891; then Maj. Lewis C. Overman, until December 7, 1891; then Capt. Thomas Turtle, until January 25, 1892, and since that date Maj. Charles E. L. B. Davis, with first Lieut. George A. Zinn under their immediate orders; Division Engineer, Col. William P. Craighill, Corps of Engineers, from January 5, 1892.

Thé approved project of defense contemplates emplacements for four 12-inch guns on lifts, six 10-inch and three 8-inch guns on disappearing carriages, eight 12-inch mortars, and submarine mines operated from two mining casemates. A project for the construction of emplacements for two 10-inch guns was approved July 11, 1891. In July and August, 1891, preparations for the work were made, plans were prepared, and the collection of a plant begun and, in September, 1891, active operations were commenced.

The site of the emplacement being 125 feet above the river, an extensive plant for handling and delivering material at the site of the work had to be constructed. A new wharf was built, 210 feet long, extending to 17 feet at low water, and provided with four derricks and a hoisting engine. An inclined railway was built up to the top of the hill where a large hoisting engine was placed. Bins for storage and high trestle tracks were constructed, and the necessary cars and machinery purchased. A pump and pipe connections for water supply of boilers and concrete mixer from the river were provided. At the close of the fiscal year ending June 30, 1892, the excavation was practically completed.

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Hampton Roads, Virginia.-Under charge of the officers in charge of defenses of Washington, D. C.

The approved project of defense contemplates, for the present, five 12-inch guns on lifts, ten 10-inch gus on disappearing carriages, thirtytwo 12-inch mortars, and submarine mines operated from two mining casemates. At the close of the fiscal year ending June 30, 1891, a project for emplacements for two 10-inch guns had been approved and work commenced. The track for steam railway had been extended, a bridge across the ditch and storage bins for concrete material built, a concrete mixer with its necessary plant installed, and a telephone line established between all parts of the work. In October, 1891, the removal of the old redoubt with its concrete gun platforms and magazines was commenced and proved a difficult and expensive piece of work. In March, 1892, tle mixing and laying of concrete were commenced.

San Francisco Harbor, California.–Officer in charge, Col. George H. Mendell, Corps of Engineers, with First Lieuts. Henry C. Newcomer and Charles L. Potter, Corps of Engineers, under his immediate orders, the latter until July 28, 1891.

The approved project of defense contemplates, for the present, eighteen 12-inch guns on lifts, twenty-three 10-inch and thirteen 8-inch guns on disappearing carriages; fifteen 12-inch, five 10-inch, and six 8-inch guns on nondisappearing carriages; one hundred and forty-four 12-inch mortars, and submarine mines operated from seven mining casemates. During the year estimates and working drawings for four emplacements were submitted. Of these one was for a disappearing and three for nondisappearing guns. Wharfage and storage facilities and the water supply were increased. Of the rock used, part was obtained from a Government quarry and part by contract at 89 cents per ton of 2,000 pounds.

The excavation necessary for the six emplacements for three 12-inch and three 10-inch guns was completed. The concrete work of three has been completed as far as it can be now done. Excepting the gaps left in the parapets in front of the three gun positions, the masonry is ready for the 3-inch top layer of bituminous rock. Almost 20,000 cubic yards of concrete have been placed in position, and necessary drains have been placed. Much back filling has been executed.

The final completion of all emplacements for guns must await definite information as to the position and the details of gun platforms for carriages, which can not be had until the models for carriages are adopted.

Estimates are submitted for emplacements for six 12-inch, eight 10. inch, and four 8-inch guns, and for one mortar battery.

Balances on hand from previous appropriations should not be considered as justifying any reduction of these estimates, as these balances pertain to works entirely distinct from those for which estimates are now submitted.

MINING CASEMATES. During the past fiscal year three mining casemates have been com: pleted, forming part of the defenses of Washington, D. C., Hampton Roads, nd San Francisco; one for the defense of Portland, Me., is expected to be completed in about six weeks; two for the defense of Philadelphia, for which allotments were made June 8 and October 10, 1891, will be completed during the present working season, and one at Charleston, S. C., is near completion. Working drawings and estimates of cost of two mining casemates for the defense of Narragansett Bay are about ready to be submitted.

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The defenses proposed for the places named and for Boston include twelve mining casemates, in addition to those completed or under way, and an estimate is submitted for $150,000, in order that the construction of six of these may be undertaken.

Two special storage sheds for submarine-mining material have been completed at New York and San Francisco, and a third required at the former place will be commenced as soon as the site can be graded and prepared.

SITES FOR FORTIFICATIONS.

The act of August 18, 1890, authorized the acquisition by condemnation, purchase, or donation of sites needed for fortifications. By this act and that of February 21, 1891, $1,000,000 was appropriated for this purpose.

In the fiscal year 1891 the greater portion of sites for one 3-gun battery and two mortar batteries at Grovers Cliff, near Boston, about 50 acres, had been acquired. The title to small portions of these sites, not then acquired, has since been passed upon, and the Attorney-General has been requested to initiate condemnation proceedings for some few lots which it has not been practicable to purchase. The sum of $7,045 was obtained by selling at auction buildings which it was necessary to remove from the site of the mortar battery.

At the southern entrance of New York Harbor places selected as sites for fortifications owned by private parties were located at Coney Island, Fort Hamilton, and Bayside (near Keansburg), N. J.

After examination of the site proposed at Coney Island a new site was selected on Plumb Island, immediately in rear of the eastern end of Coney Island.

Failing to purchase the lands referred to near Fort Hamilton and on Plumb Island at reasonable and equitable rates, proceedings were instituted by the Attorney-General, at the request of the Secretary of War, for condemning the lands in the United States courts.

The decree of the court was rendered in the case of the land on Plumb Island July 7, 1891, and the total amount paid for 50 acres to the owners under the decree was $99,547.76.

After properly recording them, the papers in the case were filed with the Chief of Engineers December 26, 1891.

In the case of lands near Fort Hamilton, 56.54 acres, the decree was rendered November 18, 1891, and the amount paid owners was $292,315.86. The Treasury Department paid, in addition, the sum of $10,452.27 for expenses incurred by the United States district attorney, making the total cost of the land $302,768.13.

The land near Keansburg, N. J., 25,3 acres,' was purchased, on authority of the Secretary of War, by agreement, September 11, 1891, at $200 per acre, and the title papers were approved by the AttorneyGeneral of the United States June 6, 1892. Payment will be made in July.

Other sites at this entrance lie west and southwest from the Fort Wadsworth reservation, and amount to about 129 acres. T'ourteen acres, with improvements thereon, were purchased for $110,000, its value, as appraised by an expert employed by the Government. Condemnation proceedings have been initiated for the acquisition of other portions of this property.

At Sheridans Point, below Washington, D. C., on the Potomac River, the purchase was authorized of 291 acres of land at a cost not exceeding $65 per acre.

But as the owners declined to sell at this figure,.con

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