Flames of Carbonic Oxide and Hydrogen. 



495 



a great extent dependent on the time during which the pressure 

 works. In order, then, to measure this force under the same 

 circumstances as when the experiment is going on, the following 

 plan was adopted. The pan of a balance was fastened by means 

 of string to the adhering glass plate, and weights were placed 

 on it by degrees until the point was reached at which, when the 

 explosion-vessel was quickly raised, the adhering plate was re- 

 moved without any marked raising of the balance-pan. The 

 weight at which this occurred was then added to that mea- 

 sured on the lever-arm. The uncertainty which attends a cor- 

 rection made in the way described does not, however, affect the 

 accuracy of the method, since the weight for this correction is 

 only a very small proportion of the entire pressure which is mea- 

 sured. The exactness of measurements conducted in this way is 

 only small ; but, as the following experiments show, it is still great 

 enough to show the remarkable laws which govern the combustion 

 of gases. By a series of experiments the volume of gas in the ex- 

 ploding-tube was found to be 18*5 cubic centims. The cylin- 

 drical flame produced was 8*15 centims. in height and 1*7 cen- 

 tim. in diameter. For the first and second of the following 

 seven experiments, a mixture was used of h parts by weight of 

 carbonic oxide with o parts by weight of oxygen, which exactly 

 serves for complete combustion. For the experiments 3 to 7 

 the same mixture was used with successive additions of n parts 

 oxygen. The pressures P and V x are, in these and in all subse- 

 quent experiments, given in atmospheres. 





Exp. 1. 



Exp. 2. 



Exp. 3. 



Exp. 4. 



Exp. 5. 



Exp. 6. 



Exp. 7. 



h 



1-0000 



1-0000 



10000 



10000 



1-0000 



10000 



1-0000 







05715 



0-5715 



0-5715 



0-5715 



0-5715 



0-5715 



0-5715 



n 



00000 



0-0000 



01850 



1 -4664 



1-8620 



2-9390 



3-6980 



P 



0-9934 



0-9804 



0-9590 



0-9658 



0-9699 



0-9763 



0-9768 



Pi 



101197 



10-5600 



8-6940 



8-1662 



76057 



6-5130 



5-6867 



fC. 



4-5 



100 



10-7 



8-5 



8-8 



8-6 



100 



The following values were found for the constants entering 

 into the calculations : — 



<r h = 0-1753 

 a =0-1547 

 <r n =0-1547 

 o-„,=0-1702 



s h = 0-9674 

 s = 1-1056 

 s n =1-1056 

 *„ = 1-5202 



w= 2403 

 «= 0-00366 

 H = 140000 

 0= 80000 



In the following experiments 8 and 9, instead of excess of 

 oxygen, the mixture of 1 part by weight of carbonic oxide with 

 0*5715 part by weight of oxygen was mixed with increasing 



