26 



SUBMARINE CABLE LAYING AND REPAIRING. 



the right have compressed air in them. Mercury is filled in 

 the bent portion of the tube and rises a certain height in each 

 stem. As the temperature rises the spirit expands, forcing 

 down the left column of mercury and raising the right-hand 



40- 



50= 



60: 



SO: 



90- 



FiG. 18. 

 Buchauan-Miller-Casella 

 Deep-Sea Thermometer. 



Fig. 19. 



Miller-Casella Thermometer 



in Case. 



column against the compressed air ; and on the temperature 

 falling the spirit contracts, and the mercury in the left-hand 

 column rises and follows up the contraction by the force of 



