OP ARTS AND SCIENCES. 223 



Soda Lime Tube. 



Grams. H T^ 



1st weight of soda lime tube 42.8731 299.54 26.G 



2d " " " " 43.1857 299.87 27.4 



Correction insensible 0.3126 



Phosphoric Anhydride Tube. 



1st weight of anhydride tube 39.5196 299.50 27.0 



2d " " " " 39.5493 300.00 27.2 



Correction insensible 0.0297 



Standard Solution of Baric Hydrate. 



Before absorption, 50 c. c. required 46.60 c. c. solution of oxalic acid. 

 After " « " 43.65 " " " 



2.95 



One c. c. of decinormal solution of oxalic acid contains 0.0126 gram 

 of H2C2O4 . 2 H.O, corresponding to 0.0044 gram of COj. 



2.95 X 0.0044 = 0.0130 gram of COo. 



»' 



r 



Total Weight of Carbonic Acid. 



Grams. 



From potash bulb 8.6740 



(( 



soda lime tube 0.3126 



" anhydride tube 0.0297 



« titration 0.0130 



9.0293 

 Reduction to vacuum 45 



9.0338 



Tare of balloon and gas 11.5907 



Tare of empty balloon 2.5569 



. Value by Regnault's method 2.5573 



The value of tlie tare of the empty balloon found by the new chemi- 

 cal method is directly comparable with that obtained by the Regnault 

 method, since there was no change in the balloon meanwhile. But 

 after this determination was finished, the balloon, as it remained stand- 

 ing in its case, having been exposed to the direct sunshine of an un- 

 usually hot June day, some of the cerate lubricating the stop-cocks 

 melted and ran down into the tnbulatures below, from which it had to 

 be removed. Thus the tare was lessened by nearly a centigram. It 



