possible to throw from the two guns at least 20 shots, each containing 50 pounds of the highest explosive. The probable chances of destructive effect from such a hail of bursting explosive can readily be conceived.

For countermining it is believed that this gun would prove particularly valuable, and far more effective than any known device; for this purpose, if for no other reason, one at least should find its place on every war vessel. When approaching waters where there is reason to believe that there are fixed mines, it will be possible by ahead fire to effectually clear the passage, destroying such mines by using shells fuzed for delayed action.

For auxiliary vessels, such as merchant craft, steam yachts, etc., that are likely to be pressed into service in case of an emergency, a battery of these guns would create a fighting strength far beyond that obtainable with any other type of gun that could be mounted on such craft. In this connection the light weight and absence of violent recoil would permit their being mounted without the necessity of strengthening decks, which would be absolutely required in mounting other guns, even of light caliber. The equipment of such vessels would thus be greatly facilitated.

ASHORE.

The gun has evidently an important place in coast defenses both in large and small calibers. The great advantage in this case is economy, as well as effectiveness. There is no known weapon approaching its effectiveness which can be furnished and mounted ready for service for less than double the cost of one of these guns. It is an undoubted fact that no gun (excepting the so-called dynamite gun) is capable of throwing a shell so destructive in its effect in proportion to total weight. It is so simple in construction, and therefore so easily taken care of, with a positive surety of its being at all times in perfect condition for service, that but slight attention need be given it when once mounted. The slight report from these guns and the entire absence of smoke and flame would make it possible to mount them in exposed places, with little or no protection, and with but slight chance of their exact location becoming known to the enemy. Particularly would this be the case during a night

attack.

For siege work the lightness of the gun and mount is of great

importance. It is readily possible to construct say a 6-inch gun of steel, weighing not over 3000 pounds, which will throw a shell containing 50 pounds of explosive gelatine to a range of at least 4500 yards. For this purpose the ease with which it may be dismounted, separated, and reassembled in the field gives it a peculiar advantage. The weight of the heaviest piece of a 6-inch gun would be 950 pounds (of a 4-inch it is 260 pounds). The practicability of transporting such a gun to localities and positions where it would be impossible to take an ordinary gun of equivalent effectiveness is of evident value. One single wrench and sledge-hammer are the only tools necessary to take it apart and reassemble, each operation being easily performed within an hour.

The 4-inch gun described weighs complete 1300 pounds, its mount 750 pounds. The gun has been fired about 200 rounds with full charges. It has functioned perfectly in every particular, the recoil easy, the breech mechanisms have worked well, and whenever attempts have been made at target practice remarkable uniformity and accuracy have been attained. Pressures have been repeatedly measured, and at no time, using same weight projectile and powder charge, has there been a perceptible difference. The limit of available range has been 2300 yards, and whenever desired this has readily been reached and could have been exceeded.

A number of full charges of explosive gelatine and also of gun-cotton have been fired, although most of the experiments have been with either dummy projectiles or for testing fuzes, with shells loaded with small charges of sporting powder.

This being the first and only practical gun built on this system, the action of the powder and in fact the whole principle being out of the ordinary, it is not to be expected that the best attainable results have been reached. So far as smoothness, easy action, recoil, and uniform action of powder is concerned nothing better could be desired.

Range of course depends entirely on the amount of force applied behind the projectile, and it will be seen that this can be increased simply by increasing the diameter of the side tubes, that is, increasing the volume of air-space between powder and projectile. Increase of this volume will permit the burning of more powder without increasing the maximum pressure.