THE ROYAL ARTILLERY INSTITUTION. 
309 
Kg. 13. 
Pig. 14. (Top of fig. 13). 
The four figures are one-half of full size. The dotted lines indicate the original figure. 
Experiment 10. A hollow brass cylinder, 
6 inches long, 2 inches in diameter, and T ^th 
of an inch thick, was heated to redness and 
cooled by half-immersion thirty-four times. 
The effect produced was the opposite to 
that which took place with the iron cylinders, 
being an expansion instead of a contraction 
at the water-line, the amount of which was 
*175inch, and it was also expanded on the 
lower edge *1 inch (see fig. 16). 
Experiment 11. A hollow gun-metal cy- 
linder was heated to redness and cooled twenty 
times by half-immersion. 
The thickness of metal being greater than 
in the last experiment, the effect at the water¬ 
line was much less, but the lower edge had 
expanded *1 inch. It began to crack all over 
at the last cooling. 
Experiment 12. A hollow tin cylinder 
was heated in linseed-oil which was brought 
to a temperature of 400° Eahr.; it was cooled by half-immersion in water 
five times. 
