sure gauges at different points along the whole length of the barrel, by which it was possible to ascertain not only how much pressure was exerted behind a projectile at the instant of firing, but how well the pressure was maintained behind it all along the bore. From this gun a torpedo shell, made thin and filled with Maximite and having a very heavy base portion filled with lead to act as tamping, was fired against an armor plate three and one-half inches thick and four feet square, demolishing it completely. The quantity of high explosive carried was only two pounds.
After the completion of the experiments at Maxim, N. J., and the successful testing of the Maxim-Schüpphaus powder by the United States Government, followed by its adoption, I went to England, with a view to the disposition of the foreign patent rights. On the 24th of June, 1897, I delivered a lecture before the Eoyal United Service Institution of Great Britain, on 'A New System of Throwing High Explosives from Ordnance.'
I explained and illustrated how a torpedo gun could be constructed which would weigh no more and cost no more than the ordinary twelve-inch seacoast rifle, but which should have a caliber twice as great, and which would stand a chamber pressure sufficiently high to throw a projectile carrying half a ton of high explosive at as great a velocity as that imparted to the usual 1,000-pound shell thrown from the 12-inch gun, and which carries only 37 pounds of black rifle powder.
I showed diagrams giving the range of destructiveness of such aerial torpedoes when striking in the water adjacent to a battleship, and claimed that such a quantity striking on board or against the armored side, under high velocity, would, without question, throw the vessel out of action.
This lecture was very widely commented upon in both the general and the scientific press, and it was stated in the House of Parliament, by one of the members who was opposing the appropriations for so many large battleships, that it would be necessary, in the event of war, and after the aerial torpedo was introduced, to keep battleships snugly in harbor and roof the harbors over to protect them.
THE GATHMANN GUN.
The Gathmann Gun Company, last year, secured an appropriation from Congress for a large torpedo gun, which was constructed by the Bethlehem Ironworks, and now lies at the Sandy Hook Proving Grounds, awaiting tests.
This gun is very like that proposed by me in the above-mentioned lecture, excepting that the caliber is not quite so large for the weight,