' THOMPSON. — ON THE EQUILIBRIUM OF THE SYSTEM. 443 



approached from the same side as in Experiment 1. This remark holds 

 good for all the following experiments. 



Experiment 3. 



As the previous experiments agreed fairly well, it was thought desir- 

 able to try a lower temperature, to make sure that the gain in weight 

 of the absorption bulbs was really due to carbon monoxide and not to 

 some impurity in the hydrogen. 



The charge consisted of fresh carbide, lime and carbon. The furnace 

 was evacuated to 0.15 centimeter and was heated to 1000° till the 

 occluded gases coming off gave a pressure of 6 centimeters, which re- 

 quired about ten minutes. It was then evacuated to 0.15 centimeter 

 with the furnace still at 1000°. Hydrogen was let in to 2.4 centimeters 

 and evacuated to 0.15. The furnace was then cooled and filled with 

 hydrogen to a pressure of 67.0 in 1 hr. 40 min. 



Power : 8.24 K. W. 

 Temperature : 1250° 

 Duration of run : 6 hrs. 



The solution of cuprous chloride had been used in a previous ex- 

 periment. 



Initial weight of absorption bulbs 183.6340 grams 

 Final " " " " 183.6372 " 



Gain 0.0032 " 



p x = 67.2 cm. of mercury 

 p 2 = 34.8 " " 

 p 3 = 90.4 " " 



0.000248 X .0821 X 286 X 760 X 90.4 n nn 

 •'■ ^o = - 19.9 X 67.2 " = °- 30 mm - 



Experiment 4. 



The charge was the same material as in the previous experiment 

 with some lime and carbon added and mixed up with the rest. 



The furnace was evacuated to a pressure of 0.2 centimeter and heated 

 to 900° for two hours. It was then evacuated to 0.15 centimeter, hy- 

 drogen was admitted to 2.4 and again evacuated to 0.15. It was finally 

 filled with hydrogen to 67.3 centimeters in 1 hr. 40 min. 



