6 Pkoi'. Dixon and Mr. Smith on 



diameter (III.), and lastly (IV.), with an iron bomb made 

 out of an ordinary mercury bottle attached to a firing 

 tube. In the latter, there are only about i,6oo sq, cm. of 

 surface exposed for a volume of 3,075 cc. ; that is to say, a 

 surface only iV as great as that exposed in the 4 mm- 

 tube, the capacities being, however, nearly equal. From 

 the analyses it would appear that although the amount of 

 surface exposed to the gases has some influence on the 

 amount unburnt, the influence is not very great, and there- 

 fore it seems improbable that the incompleteness of 

 combustion is due to the cooling action of the surface of the 

 vessel. 



III. IV. 



I -01 



A number of experiments were made with a mixture 

 of carbonic oxide and oxygen. 



In the first series of experiments the 9 mm. tube was 

 employed, and in the second series the iron bomb. The 

 mean results are given below. 



