THE ROYAL ARTILLERY INSTITUTION. 
205 
Pig. 3 shows the difference in the indent made by 
a cast-iron and a wrought-iron spherical shot—559 
was made by a wrought-iron shot of 71 lbs, weight, 
the depth of indent was 3 A" and its diameter 9*"; 557 
was a cast-iron service 68-pr. shot, the indent being 
2‘5" in depth and 8*5" in diameter, both these shot 
were fired with the service charge, the velocities being 
1413'with the cast-iron and 1385' with the wrought- 
iron shot. 
In Table B will be found the results obtained from 
wrought-iron shot of various natures which have been 
fired against iron plates. 
Fig. 3. 
Steel Shot. 
The first trial of steel shot in this country was in January, 1859. On the 
6th of that month six flat-headed steel shot were fired from an Armstrong 
32-pr. B. L. rifled gun with 6 lbs. charges at the “ Trusty” floating battery, 
the ranges varying from 50 yds. to 480 yds.; two shot which struck at the 
junction of the plates penetrated and 9 \ ,r respectively; the remainder, 
after ricochet from water, merely caused indents, varying from 0*75" to 
1*25". Purther experiments were made in September, 1859, with puddled 
steel and homogeneous* iron flat-headed shot. They were fired from Sir W. 
Armstrong's 80-pr. rifled gun, at iron plates of various thicknesses up to 3 in., 
attached to a target of oak, representing the scantling of a 50 gun frigate; 
the result of this experiment is thus reported :—• 
“ Puddled steel and cast-iron shot were fired at the 3" plates, and as the target 
was now much shattered similar shot were fired at the 2J" target. In each case 
the shot passed through both plate and scantling, the puddled steel shot entire, the 
cast-iron in fragments ; the cast-iron damaging both plate and timber to a greater 
extent than the puddled steel.” 
In a further trial of the “ Trusty," which took place at this time, shot of the 
same description were fired. Prom the report on this experiment it appears 
that at 400 yds. range a puddled steel shot drove in a large portion of plate 
“ strewing the main-deck with fragments of plate and timber," the report 
goes on to state,— 
“ The only shot which on the first day, fairly penetrated both plate and timber 
was one of homogeneous iron, which struck near the centre of one of the upper 
plates, broke off a portion of plate 21" X 11" and forced its way through the 
scantling on the upper deck where it lay partially imbedded.” 
The shot weighed 78 lbs., and were fired with 12 lbs. charges. At 
200 yds. range, a shot penetrated the plate and 10" into the timber; a 
second shot, striking near the previous one, penetrated the side, and drove a 
portion of plate to the opposite side of the vessel, “ on which it was buried 
* “Homogeneous metal is evidently a variety of cast-steel, containing a small proportion of 
carbon, and is intermediate in that as well as other respects between malleable iron and cast-steel.’* 
—Percy’s Metallurgy. 
