Prof. Graham ok the Law of I he Diffusion of Gases. 135 



1085*7 measures hydrogen were replaced by 278*1 mea- 

 sures air. 



— - — - = 3*900 = diffusion- volume of hydrogen. 



Exp. 6. — Same bulb, but in this and the succeeding experi- 

 ment, the bulb was attached to the end of a balance, and 

 counterpoised, so that it adjusted itself spontaneously in the 

 jar filled with water, in which it floated. Thermometer 60°. 



1085*7 measures hydrogen were replaced by 279*1 mea- 

 sures air. 



1085-7 



2791 



== 3-890 = diffusion-volume of hydrogen. 



Exp. 7. — Same repeated. Thermometer 61°. 

 1085*7 measures hydrogen were replaced by 282*2 mea- 

 sures air. 



1095*7 



282-2 



= 3*847 = diffusion- volume of hydrogen. 



The results of these five last experiments, with the same 

 instrument are, in one view, 



New hydrogen gas was made for each experiment by the 

 moderate action of dilute sulphuric acid on zinc, and it was 

 collected in the diffusion-instrument from the beak of the re- 

 tort. The observations could not be made with so much ac- 

 curacy as to entitle us to place any reliance on more than two 

 decimal places of the calculated diffusion-volumes. A great 

 variety of experiments were performed on the diffusion of 

 hydrogen with the diffusion-bulbs employed above, and se- 

 veral others of similar construction, principally with the view 

 of discovering the cause of the slight variations in the re- 

 sults, and why the quantity of return-air was pretty uniformly 

 somewhat less than the theoretical quantity, which has the 

 effect of increasing the proportion of the hydrogen diffusion- 

 volume. 



It appears, that when the stucco-plug is in a parched state, 

 Thin! Series. Vol.2. No. 9. March 1833. 2B 



