LABORATORY SUPPLIES AND CHEMICALS 



83 



2183 



2183 CALORIMETER Parr's Adiabatic with "Illium" bomb. 



Another form of Calorimeter, and that of the Adiabatic type, has just been per- 

 fected, and its operation in actual use has been so eminently satisfactory that it is now 

 being regularly manufactured for the trade. It is the completion of a design which has 

 been in process of development for some years by Professor S. W. Parr of the Univer- 

 sity of Illinois. 



The adiabatic principle has been 

 secured, not by the use of the Dewar, 

 or vacuum arrangement, with its 

 somewhat questionable immunity 

 from variation, nor is use made of 

 any chemical or electrical method of 

 heating the surrounding water. The 

 principles involved are carried out as 

 follows: 



A supply of hot and cold water is 

 automatically provided immediately 

 underneath the desk on which the 

 calorimeter is installed. This may be 

 drawn upon either to raise or lower 

 the temperature of the water in the 

 surrounding medium. By means of a 

 stop cock and overflow, hot water, 

 for example, can be instantly dis- 

 charged into the jacketing water. The 

 lag, therefore, is only that incident 

 to the stirring of the water and the 

 response as shown on the thermom- 

 eter occurs at once. 



Showing Water Reservoir Heated by 

 Gas Flame 



Price Without Motor or Thermometer $375.00 



