The estimates for the next fiscal year are bases on expenditures for a similar period last year, taking into consideration remaining balances and supplies on hand.

The supplies produced during the past fiscal year include 1,750 pieces of ordnance, 2,361 artillery carriages and caissons, 802,525 small-arms, 794,055 sets of accouterments and harness, 1,674,244 projectiles for cannon, 12,740,146 pounds of bullets and lead, 8,409,400 pounds of gunpowder, 169,490,029 cartridges for small-arms. These are complete articles, in addition to large quantities of the same kind of supplies partially made up at the arsenals.

The ordnance supplies furnished to the military service during the fiscal year include 1,141 pieces of ordnance, 1,896 artillery carriages and caissons, 455,910 small-arms, 502,144 sets of accouterments and harness, 1,913,753 projectiles for cannon, 7,624,685 pounds of bullets and lead, 464,549 rounds of artillery ammunition, 152,067 sets of horse equipments, 112,087,553 cartridges for small-arms, 7,544,044 pounds of gunpowder. These supplies were in addition to large quantities of parts provided for repairs in the field.

The capacity of the arsenals for the manufacture of munitions of war has been increased during the year, and that increase is still going on, so far as the means appropriated will admit. Supplies manufactured at the arsenals are of better quality and less cost than similar articles abounded by contract or purchase.

The National Armory at Springfield, Mass., can turn out 300,000 of the best quality of rifle muskets annually.

Possession has been taken of Rock Island, Ill., in pursuance of an act of Congress, and the requisite buildings for an arsenal there are in progress.

There is on hand a stock of three-quarters of a milition of first-class rifle small-arms, exclusive of the arms in the hands of the troops, since increased to a milion and a quarter.

The introduction of breech-loading arms for the military service generally is recommended.

The selection of a site for a general depository of gunpowder and the erection of suitable magazines thereon is recommended. In that connection the construction of a Government powder mill of sufficient capacity to make standard and proof powder and gun cotton is also recommended.

The procurement of a suitable ground for the proof and experimental firing of ordnance and small-arms is urgently advised as a most essential want of the military service.

A heavy 20-inch gun has been successfully cast and finished, and is ready for trial. The object of the trial is to demonstrate whether the destructive effects of such a gun, warranted by theory, will be practically realized, and to settle the question of the largest effective caliber for sea-coast cannon.

The armies in the field have been amply supplied with good and effective arms, equipments, and ammunition, and the armament of our fortifications has been kept in good other and strengthened during they year.

The Chief Engineer reports that the operations of his bureau for the last year embrace special efforts to prepare the coast defenses to receive the heavier and most suitable artillery for combating ironclad vessels, the construction of field-works and lines with the armies in the field; the preparation and service of pontoon bridge equipage,