120 ANNUAL OF SCIENTIFIC DISCOVERY. 



Pressures {Maximum). First shot, 21,000 pounds per square 

 inch; second shot, 21,000 pounds per square inch; third shot, 

 25,000 pounds per square inch ; fourth shot, 21,000 pounds per 

 square inch. 



Time of loading, running into battery, elevating, and priming, 

 8 minutes. Army and Navy Journal. 



LARGE GUNS. 



Krupp\s Cannon. One of the most important establishments 

 of Prussia is that of Mr. Krupp, which, from the character of its 

 work, must be ranked among the first manufactories on the Euro- 

 pean continent. 



This establishment was represented at the Paris Exhibition by 

 4 or 5 steel cannon, ranging in size from the smallest field piece to 

 the heaviest calibre, the latter being perhaps the most powerful 

 cannon in existence. This immense gun is a dried breech-loader 

 of 14 inches bore, constructed wholly of cast steel, and \yeighs 

 1,000 cvvt., and the cannon (intended for the armament of a coast 

 fortification) consists of an inner barrel having several cast-steel 

 rings or reinforces welded around it while hot. 



The inner barrel, the most important part of the whole, weighs 

 400 cwt. and is wrought from a pig of 850 cwt., under a hammer 

 of 1,000 cwt. The loss of its original weight is caused bv the fall- 



c* / 



ing off of the head or mould end, by forging, turning and boring. 

 The cast-steel rings weigh all together 600 cwt. The breech 

 stopper is Krupp's own invention. A charge of gunpowder of 

 100 pounds is required to project the shot, which weighs 1,100 

 pounds. 



The cannon is mounted on a steel carriage 40 feet long by 9 



^j Cj ' 



feet wide, and weighing 500 cwt. The mechanism for manoeu- 

 vring this enormous mass of metal is so arranged that the proper 

 elevation, declination, etc., can be given by one or two men with 

 the greatest facility, and with such rapidity that a passing vessel 

 can be aimed at with accuracy. 



Euelle Great Gun, at Paris Exhibition. Tt consists of a cast- 

 iron body, strengthened by 2 steel coils ; the weight is a little less 

 than 37 tons, and the diameter of the chamber rather less than 17 

 inches. It is a smooth-bore breech-loader. Its solid spherical pro- 

 jectiles are of 600 pounds weight, and the shell of the same form 

 weighs 420 pounds, and contains 18 pounds of powder; the 

 charges for the two are respectively 100 and 66 pounds. It is 

 mounted on a cast-iron carriage, weighing 29 tons. The shape is 

 long and bottle-like, longer in proportion to its diameter than the 

 Prussian big gun. It is intended for port service. 



American Guns. The 15-inch gun is to be regarded as the lowest 

 grade of the heavy smooth-bore ordnance of the future. This, 

 with a charge of 100 pounds of powder, is a more formidable 

 weapon than any European gun ; the 20-inch gun, with 175 

 pounds of powder, has proved entirely successful, and no foreign 

 iron-clad could resist a single well directed shot from such a gun, 

 with this charge, within a distance of 100 yards. This monster 



