THE EOYAL ARTILLERY INSTITUTION. 
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Experiment 5. A solid cylinder of wrought-iron, 3 inches in diameter 
and 6 inches deep, was heated and cooled by being immersed half its depth 
in water fifteen times. 
The greatest contraction took place a little above the water-line and on 
the lower edge, being in each case -45 inch; the upper edge was reduced 
only T inch. 
Fig. 9. Fig. 10. 
One-half of full size. The clotted lines indicate the original form. 
A swell of metal took place on the two ends, but was greatest on the 
bottom, or that cooled in water, being T5 inch in height. 
The fibre of the iron opened at the fifteenth cooling (see fig. 9). 
Experiment 6 . A wrought-iron cylinder exactly similar to the last was 
cooled by being immersed to two-thirds its depth fifteen times. 
The greatest contraction, amounting to *4 inch, took place a little above 
the water line; the upper edge was ’05 inch smaller, and the lower edge *35 
inch, while the swellings on the ends were nearly the same as in the last 
experiment (see fig. 10). 
The separation of the fibre took place at the fifteenth cooling. 
Experiment 7. Two flat pieces of wrought-iron, each 12 inches long, 6 
inches deep, and *5 inch thick, were heated and cooled twenty times, one 
being immersed to half, and the other to two-thirds its depth in water. 
That immersed one-half had contracted or become indented on the ends 
fully *3 inch; the other had similar indentations, but to only one-half the 
amount. They were both turned up into the form of an arc, had thickened 
