THE SPECIFIC HEAT OF AMMONIA. 

 By Henry A. Babcock. 



Presented by Henry Crew. Received Dec. 1, 1919. 



CONTENTS. 



Page 



I. Introduction 327 



II. Experimental Method 327 



III. Apparatus 330 



1. Calorimeter 330 



a. Calorimeter Tube 330 



b. Calorimetric Fluid 330 



c. Liquid Container. Calorimeter Stirring . . . 330 



d. Heating Coil 331 



e. Thermometer 332 



f. Vacuum Jacket 332 



g. Enclosing Vessel 332 



2. Energy Measuring Apparatus 333 



a. Circuits 333 



b. Heating Coil 333 



c. Potentiometer and Galvanometer 333 



d. Batteries 333 



e. Standard Cell 333 



f. Standard Resistance 333 



g. Chronograph 333 



3. Thermometric Apparatus 333 



a. Standard Thermometer 333 



b. Observing Thermometer 334 



c. Wheatstone Bridge 334 



d. Thermometer Switch 336 



e. Galvanometer 336 



f. Apparatus for Calibration of Standard Ther- 

 mometer 337 



g. Apparatus for CaUbration of Observing Ther- 

 mometer 337 



4. Constant Temperature Bath 337 



a. Tank 337 



b. Oil 337 



c. Stirring 337 



d. Adjusting Heater 337 



e. Main Heater 338 



f. Regulating Heater 338 



g. Temperature Regulator 338 



h. CooUng Coils 338 



i. Removable Cover 338 



IV. Laboratory Equations and Methods of Measurement . . . 338 



1. Laboratory Equation for specific heat at constant specific 

 volume of a mixture of liquid and vapor 338 



2. Laboratory Equation for Energy Input to Calorimeter . 339 



3. Ratio of Volt-box Coils 340 



4. Laboratory Equation for the Calorimeter Temperature 

 Change: CooHng Correction 340 



