1863.] 



467 



throughout, and the expansion was least a little above the water-line, 

 t. e. it did not contract to its original dimensions. 



The subjoined figures (half the full size) show the changes pro- 

 duced on the 9-inch cylinders after every five heatings. (Experi- 

 ments 2 and 4.) 



Fig. 22. 



12" Cylinder, 9" high, j" thick. 

 Vide fig. 4. Cooled by ^-immersion. 



Fig. 23. 



12" Cylinder, 9" high, |" thick. 

 Vide fig. 7. Cooled by f-immersion. 



No. 1. External surface, original form. No. 1. External surface, original form. 



2. after 5 coolings. 2. ,, after 5 coolings. 



3. 10 3. 10 



4. 15 4. 15 



5. i. .. ,, 20 ,, 5. ,. ,, ., 20 ,. 



