92 Mr. D. Waldie's Experimejital Researches 



Now let carbonic oxide be treated in the same way. 

 Vols. Sp. gr. DifFus. Inv. of quant. 



1 16- oxygen 3*75 x 2 = 7*5 



2 14<'12 carbonic oxide 4* x 1 = 4* 



In this case the flame of oxygen should be larger than that 

 of carbonic oxide (that is, when burning in each other), be- 

 cause their diffusibility is nearly equal, and the larger quantity 

 of carbonic oxide is required. On trial I found that it was 

 so in fact ; the only instance I have seen with unmixed gases 

 where the oxygen flame is larger than that of the other sub- 

 stance. In the same way the flames of oxygen and sulphu- 

 retted hydrogen approximate to each other in size. 



The flames of chlorine and hydrogen in each other ought 

 to depend on their diffusibility alone, as their combining pro- 

 portion is equal volumes. Not having the chlorine in the 

 gas-holder I could not ascertain its size well ; but from the 

 trials I have made it is very small, similar to that of oxygen. 

 So also is that of nitrous oxide, and nitrous acid has also a 

 small flame. The flame of hydrogen in these gases is very 

 large, of a greenish or yellowish colour, darkish in centre, 1, 

 (fig. 2) brightest and hottest about the middle of the outer 

 part, 2, but very diffused in its appearance. 



The flame of oxygen in hydrogen consists of a dark un- 

 mixed central narrow portion, 1, (fig. 3) surrounded by a 

 lilac blue flame of small size, 2, and then by a dark yellowish 

 envelope and tail, 3. The heat is concentrated in the blue 

 portion, where the platinum wire fuses and sparkles brilliantly, 

 the heat being compressed into so small a space. 



The flame of oxygen in olefiant gas is a very beautiful and 

 instructive example. It is necessary to premise, that as the 

 oxygen is the least diffusible of the two gases, and as it re- 

 quires only one third of its volume of olefiant gas to form a 

 proper combustible mixture, both of these circumstances con- 

 spire to make its flame small. In this, therefore, we have a 

 small light blue flame, darkish in centre ; in this blue flame is 

 the strongest heat which fuses the platinum wire, 1 and 2, 

 fig. 4 ; surrounding this and stretching far above it was a 

 dull strong yellow flame, h, red at the edges and dark in the 

 centre, 3, evidently consisting of solid red hot charcoal, a 

 very large quantity of which was separated as smoke, and 

 adhered to the sides of the flask. 



