396 Royal Society : — On the Change of Form assumed by 

 Fig. 9. Fig. 10. 



One-half of full size. The dotted lines indicate the original form. 

 Fig. 11. 



One-fourth of full size. 

 Experiment 8. — Two hollow wrought-iron cylinders, 9 inches 

 deep and 12 inches in diameter, were heated and cooled, one by- 

 simple exposure to air (fifteen times), and the other by total 

 immersion in water (ten times). No alteration occurred in the 

 form of either*. 



* The cylinder which was cooled in air weighed, before the experiment, 49 lbs. 

 14*5 ozs., and after the experiment 49 lbs. 11 ozs., showing a loss by scaling of 

 3-5 ozs. 



During the progress of the experiment, however, it was frequently weighed, and 



