222 



ill. 



Volume of air taken .... 148*1 

 After addition of hydrogen . . 236'04 

 After explosion 143-30 



Nitrogen . . . 79 '139 



Oxygen. . . . 20-861 



100-000 



* 

 IV. 



Volume of air taken . . . . 149*14 

 After addition of hydrogen . . 248*57 

 After explosion 155*28 



Nitrogen . . . 79*150 



Oxygen. . . . 20*850 



100-000 



We are still engaged in experiments on this and some other points 

 of gas analysis, and hope to have the honour of communicating our 

 results before long. 



DESCRIPTION OF THE FIGURES. 

 Fig. 1 represents the whole apparatus. 

 Fig. 2 represents the clamp with the fine adjustment attached to it. 



A is the part which slides up and down the vertical rod ; it is furnished on 



the inside with a small steel peg which moves in a groove, thus causing this 



arm always to remain in the same plane. 



C D is a tube through which the rod F carrying the clamp passes. 

 E is a screw which retains the rod F in its place, and by means of which 



the friction of the rod passing through the tube can be increased. 

 G is the fine adjustment. As this small cylinder is turned round to the right 



or to the left, so the string either above or below it is wound on to it, and 



consequently the rod F raised or lowered. 



H is merely an arrangement by which the string can always be tightened. 

 K is a peg so placed with regard to the stop L, that when, by turning the 



clamp round, it is pressed against the stop, the tube is then in the right 



position for applying the final adjustment and reading off. 



