332 



BABCOCK. 



Thermometer. 



Platinum resistance thermometer, built into calorimeter. 



Enclosed in flattened steel sheath, similar to heating coil 



sheath. Extended entire length of calorimeter tube. 



Averaged differences of temperature at different levels. 



Vacuum Jacket. 



Wide mouthed ^ Dewar flask, enclosing calorimeter tube. 



Top closed by asbestos board calorimeter cover supported 



on asbestos board ring carried by enclosing vessel. 



EOSON STORAGE CELLS 



5WITCH 



TO CHRONOGRAPH 



POTENTIOMETER CIRCUITS 



Figure 4. 



g. Enclosing Vessel. 



Brass cylinder fitted with screwed-on cover, totally im- 

 mersed in constant temperature oil bath. Cover threads 

 packed with red lead mixed with machine oil. Cover 

 provided with brass tube conveying leads and stirring shaft 

 from the calorimeter to the outside. Leads were insulated 

 by small glass tubes fixed inside the brass tube. 



6 There is no particular advantage in this contracted neck shown on the 

 Dewar flask. This bottle was at hand, so the rest of the apparatus was built 

 to fit it. 



