then and still has a good effect in securing a healthy competition among bidders and in insuring to the United States the needed supplies at fair prices, when the purchases are of any considerable amount. But there are many cases constantly occurring at our manufacturing establishments where small supplies are required, and where the expense of advertising largely exceeds, in some instances, the value of the purchases, to say nothing of the additional loss by the consequent delay in this mode of purchase. I refer now to the minor incidentals, the necessity for which cannot be economically anticipated.

To meet such cases, and in the interest of a true public economy I would recommend that section 3709, Revised Statutes, be amended by inserting after the word "services" on the first line the words "in excess of one hundred dollars," so that the section shall then read:

SEC. 3709. All purchases and contracts for supplies or services in excess of one hundred dollars, in any of the Departments of the Government, except for personal services, shall be made by advertising a sufficient time previously for proposals respecting the same, when the public exigencies do not require the immediate delivery of the articles, or performance of the service. When immediate delivery or performance is required by the public exigency, the articles or service required may be procured by open purchase or contract, at the places and in the manner in which such articles are usually bought and sold, or such services engaged, between individuals.

Existing law permits the Interior Department to make purchases in open market to the amount of $500.

THE ARMAMENT OF FORTIFICATIONS.

The Board on Fortifications or other Defenses appointed under the act of March 3, 1885, rendered its report to Congress on the 23d day of January last. That report gives an exhaustive survey of the subjects that came within the province of the Board, and closes with clear, definite, and practical recommendations, accompanied by estimates, which should they meet with favorable action from Congress, would result in placing our principal ports in a secure state of defense, and in insuring the production within our own borders, at an early day, of the steel forgings requisite for the construction of the heaviest armor and guns. The report indorses the recommendation of the Gun Foundry Board touching the establishment by the Government of two gun factories, one for the Army and the other for the Navy; and Congress also by legis lation at its last session, in enabling the Navy Department to begin the establishment of such a factory at the Washington navy-yard, practically endorsed, and gave effect to that recommendation. A bill embracing similar provisions with respect to the establishment of an Army gun factory at the Frankford Arsenal was indeed passed last session by the Senate, but failed to obtain the concurrence of the House, and still remains in conference. Under one provision of that bill $400,000 were appropriated for completing and testing the guns which the Department has now under construction, for procuring guns, carriages, powders, projectiles, &c., and "for the purchase, manufacture, and

erection of the necessary tools and machinery for the finishing and assembling of heavy ordnance at the Frankford Arsenal, Philadelphia, Pa." By still another provision $6,000,000 were appropriated, to be available for a period of six years from the date of contract, for the purchase of rough-bored, turned, and tempered steel forgings, suitable for heavy ordnance, adapted to modern warfare,-the amount appropriated to be divided equally between the Army and Navy. The feat. ures of this bill as a whole are judicious and well devised, except that the very important question of fortifications is wholly ignored. But no doubt great good would have resulted from the passage of the bill in its present shape by Congress. The want of machine shops under its own control, fully adequate to the manufacture of type guns of various calibers, has been a great obstacle to the Department in its experimental work and in the constructional development of heavy gans. Under the provisions of this bill a start would have been made in the right direction, by laying at least the foundation of a gun factory at the Frankford Arsenal, and which under a fostering legislation would be added to from year to year. Thus the effect of the annual appropriations would be cumulative, and the Department would ultimately possess a fully equipped and organized factory, capable of producing both type guns and, in limited supply, the guns for issue to the service. The advantages accruing to the Government from establishments of its own have been so fully and forcibly presented in the report of the Gun Foundry Board as to require no reiteration or enlargement here. It will suffice to say that an Army gun factory is a great want, and it is most earnestly recommended that Congress take such action at its next session as will place the Department on, at least, an equal footing with the Navy in respect to such an establishment. The appropriation of $6,000,000 for steel forgings is perhaps scarcely sufficient to arouse much competition among steel makers, but it would doubtless prove a healthful stimulus to those manufacturers who are now engaged in supplying the Government with gun forgings. The amount recommended by the Board on Fortifications or other Defenses for gun metal for the first year alone was $8,000,000, while for inaugurating the production of armor plates, laying the foundations for fortifications, manufacturing gun carriages, submarine mines, torpedo boats was $13,500,000, making the total amount recommended for the first year $21,500,000. In these recommendations of the Board this Departmeet fully concurs.

Through the failure of the regular fortifications appropriation bill to become a law at the last session of Congress, serious injury has been sustained by the Department, and its operations as regards the armament for fortifications, for the fiscal year 1886–87, such as the completion and test of the experimental guns under construction, the further development of powders and explosives, and the alterations of carriages for mounting existing guns have practically ceased, except in so far as that work is continued over from last year by existing contracts.

And not only has the work come to a standstill, of itself a great evil, but the personnel of the Department, employed on the work, has been almost entirely discharged. The force of civilians employed at the proving ground, consisting of men of long experience in handling guns and explosives, and doing the technical work in connection with an ordnance proving ground, has been lost to the Department, and the operations now practicable at that point must be carried on by means of enlisted men taken from the arsenals, who will require very considerable instruction and practice to fit them for the proper discharge of their new duties.

At the Watertown Arsenal, where the Department has had under con. struction the experimental 10-inch wire guns, the alteration of sea-coast carriages, and the manufacture of gun-sights and other supplies pertain. ing to the armament of forts, work has practically ceased, and the large force of skilled men has been discharged. The expense and labor at tending the recommencement of work, like the installation of new work, is very considerable, and is made apparent in the increased cost of the articles produced. The difficulty also of getting skilled men for such technical work, of organizing, of instructing, of getting the right man in the right place, and of determining the best and cheapest manner of doing the work-all matters of great moment-has to be again encountered and overcome after a period of enforced idleness. But the difficulty of procuring good men, when work is resumed, becomes more difficult than ever, from the feeling of uncertainty regarding the permanency of their employment.

The interruption of the work in hand has proved a source of great discouragement, nevertheless every effort has been continued to perfect the plans of the Department and to maintain the well-reputed interest and ability of its officers on these subjects, under the hope, which is believed to be well grounded, that this embarrassment is but temporary. Following is a brief summary of the present condition of the work, and of the results obtained in experimental trials during the year.

Experimental 12-inch B. L. Rifle, cast iron.

The trial of this gun has been continued during the past year, under the supervision of the Board for Testing Rifled Cannon, &c., who have submitted a progressive report (Appendix 10). The total number of rounds thus far fired is 137; of which number 123 have been with the full charge of 265 pounds of powder, and 79 rounds with an 800-pound projectile. The mean pressure for one hundred observations has been 27,998 pounds per square inch of powder chamber, and the maximum pressure registered in any single round 34,400 pounds per square inch. This statement of course discredits the result obtained in the 5th round, where 47,250 pounds pressure per square inch was registered. But as in that round only the light charge of 150 pounds hex

agonal powder, with a 700-pound projectile, was employed, and the velocity obtained was but 65 feet greater than in the preceding round, where with the same charge of powder, though fired under a somewhat less density of loading, only 24,600 pounds pressure was registered, it is clear that in this instance the indication of the gauge was erroneous. All the preceding rounds fired confirm this conclusion. The record was at the time reported as being unreliable from the fact that the gauge was displaced in firing, from want of a solid support. The different lots of brown powder tested have shown some variation from one another with respect to velocity and pressure; but limiting the pressure to about 28,000 pounds per square inch, as the highest safe limit for cast iron, the muzzle velocity for an 800-pound projectile will probably not average above 1,750 feet even with the exercise of the greatest care in the manufacture of the powder. The total energy thus imparted to the projectile is about the same as would be obtained from a full power 103-inch steel rifle, the weight of which is 21.5 tons less than that of this 12-inch castiron gun.

At the 50th round erosions were observed in the bore, which increased in number and in gravity of character as the firing progressed. At the 137th round the erosion had become so pronounced along the front slope of the powder chamber and in the shot recess that the Board decided to discontinue the firing, believing the gun to be unsafe (Appendix 10). It is thought that by means of a lining tube, inserted either at the outset or after the bore has begun to suffer from erosion, the life-time of such a gun would be prolonged; but the Department has now partly completed a 12-inch cast iron gun, to be lined with a steel tube, and it is thought expedient to await its trial before lining the present 12-inch gun. It is well understood that erosion of the bore is one of the chief sources of deterioration in modern guns firing heavy charges, and that its action is so energetic that a renewing, by some means, of the surface of the bore is necessitated after a comparatively small number of rounds have been fired. The larger the powder charge and the higher the pressures exerted by the gases, the more aggravated will be the effects from erosion; while, on the other hand, those effects will be diminished as the bore is straight, or free from slopes or shoulders that obstruct the free passage of gas, and as the metal of the bore is dense, smooth and infusible. In the latter respects, steel has obvious advantages over cast iron; but there are also, great differences between different grades of steel. The erosion of the 12-inch cast-iron gun, after the 137th round, is well shown by the photographs accompanying the report of the Board. (Appendix 10.)

The trial of the 12-inch cast-iron gun, tubed with steel should furnish useful information with respect to the limit of endurance that may be attained with cast-iron guns, when thus protected against the destructive effects of erosion.

Experimental 12-inch B. L. Rifles.-Cast-iron tubed with steel; cast-iron hooped and tubed with steel.

The contracts for the manufacture of the above guns, although extended about one year in each case, were not completed by June 30, 1886, the end of the fiscal year, at which time the appropriations made under the act of March 3, 1883, and applicable to their manufacture, expired by limitation of law. Accordingly a fresh appropriation is now necessary in order to complete the guns, and a provision to that effect was made a clause of the fortifications bill at the last session of Congress, but failed, with the fortifications bill, to become a law. The present stage of progress on the guns is as follows:

The 12-inch B. L. rifle, hooped and tubed, has been assembled, and the breech mechanism is ready to be fitted, so that there remains in order to complete the gun only the finishing of bore and exterior of chase, and the rifling. The body for the 12-inch B. L. rifle, tubed, having been successfully cast at the fourth trial, is now rough bored and turned, and counter bored for receiving its tube; the tube is rough turned and the breech mechanism is in readiness to be fitted to the gun. Should Congress reconsider its action on the fortifications bill for the year 1886-'87, this coming winter, and appropriate the necessary money, it will be practicable to complete both guns within the present fiscal year.

Experimental 12-inch M. L. Rifled Mortar, cast-iron steel-hooped.

The trial of this piece has been in progress, under the supervision of the Board for Testing Rifled Cannon, &c., since July, 1885, and a progress report is contained in Appendix 11. The full charge for the mortar was fixed at 52 pounds and the weight of the charged shell 610 pounds. With full and half charges the velocity and pressures were as follows:

The following ranges were obtained with full and half charges: