110 ANNUAL OF SCIENTIFIC DISCOVERT. 



the inner welds, which no subsequent heating and hammering can perfect. 

 By the process Mr. Ames has introduced, the section around the bore is 

 molded first, and by each subsequent heat the molds are extended out- 

 ward. The process in detail is as follows : A bar of round iron 18 feet 

 long, ten inches diameter at one end and 14 at the other, is made to serve 

 as the handle of the gun. Upon the larger end of this are welded one 

 by one large bars of iron of about two feet in length, until a round mass has 

 been formed of 30 inches in diameter, perfectly solid. This is to serve as 

 the breech of the gun, and the end is upset by a horizontal steam hammer 

 until it is perfectly even and true. After this the gun is built up of sections 

 of the full size (circumference) of the gun, of about five inches in length, 

 the entire gun (14 feet long when completed) being composed of 30 trans- 

 verse sections. These sections are made up as follows : A cylindric il 

 block of the best refined iron is turned out seven inches long, ten inches 

 in diameter, and with a 4-inch hole through its length. This is fitted 

 closely into an iron band or hoop made from bars of iron six by seven 

 inches ; and this is again fitted into another band of three inches in thick- 

 ness. These bands are closely welded, and as solid as the best mechanism 

 can make them. When thus put together it will be seen that the whole 

 forms a cylindrical section (or wheel) of 30 inches in diameter : the greater 

 length being near the center. The hole at the center permits the impurities 

 of the metal to be worked out from the inner rings, while being heated and 

 hammered, while the scales which may accumulate on the outer rings, are 

 permitted to fall outward as the weld extends towards the circumference. 



The trials made wiih guns thus constructed, have, it is reported, been 

 most successful. With 20 pounds of powder and 150 pounds of shell, 

 with an elevation of 15, a range of about four miles is attained; and 

 with an elevation of 23 , a range of nearly seven miles. 



Guns vs. Armor. Mr. Fairbairn, the celebrated engineer, stated to 

 the British Association at its last meeting that the conclusion he had 

 arrived at from all the experiments made in England in relation to guns 

 and armor, was " that no ship can be made to carry plates sufficient to 

 withstand our guns, and it would probably be better to have no plating 

 at all. We should thus have ships more lively in the water and better 

 adapted for manoeuvring and at far less cost." 



English Views of Giui-Cotton. As has been stated in a previous 

 article in this volume, the report of the French chemists and military 

 men, in reference to the use of gun-cotton as a substitute for gunpow- 

 der, has not been favorable ; but from a Committee report, presented 

 at the British Association, September, 18G4, by Mr. Scott Russell, it 

 appears that opposite conclusions have been arrived at by the English 

 experimenters. Mr. Russell stated that General Hay, of the Ilytho 

 School of Musketry, had constructed a new form of cartridge suited 

 for the Whitworth rilie ; th^ he had found that the use of gun-cotton 

 was cleanly, and had not the disadvantage of fouling the gun ; that it 

 had much less recoil, although the effect was the same ; that one-third 

 of the weight of charge was the equivalent proportion, and that it did 

 not heat the gun. The General had fired at a target with gun-cotton 

 at oOO yards. Twelve successive shots were all placed in a space one- 

 foot wide by two feet high, and the value of the practice was meas- 

 ured by the fact that the mean radius of deviation from the center was 

 between nine and ten inches. Thus, therefore, the use of gun-cotton 



