2:^4 REpoiiT—isro. 



Volume of nitric oxide used 20-99 



Volume after the admission of nitrous oxide . . 102'44 



Volume after the admission of hydrogen 233-90 



Volume after explosion 123-10 



Volume after the admission of oxygen 167-62 



Volume after explosion 122-08 



Hence we find, on the supposition that the nitrous oxide is pure, the 

 amount of nitrogen and oxygen in the nitric oxide in 100 volumes : — 



By experiment. Calculated. 



Nitrogen .' 52 50 



Oxygen 47 50 



99" Too 



But, on the supposition that the nitric oxide is pure, this analysis gives re- 

 BultB according with my own. 



In 100 volumes of nitrous oxide we find- 

 By experiment. Calculated. 



Nitrogen 100-98 100 



Oxygen 49-18 50 



The general result of these analyses is : — 



(1) The volume of the oxygen in the nitrous oxide is smaller than the 

 volume of the nitrous oxide used by 0-61 to 2-13 per cent. 



(2) The volume of the nitrogen is larger than the volume of the nitrous 

 oxide used by 0-38 to 1-66 per cent. 



That the volume of the oxygen is smaller than half the volume of the 

 nitrous oxide used can be explained by the presence of a certain quantity of 

 nitrogen, ranging from 0-61 to 2-13 per cent., a quantity much smaller than 

 the total amount of nitrogen mixed with the nitrous oxide, which was found 

 to be between 3-5 and 5 per cent. 



That the volume of the nitrogen contained in the nitrous oxide is larger 

 than the volume of the nitrous oxide used could be explained by the presence 

 of a gas containing more nitrogen in a molecule than nitrous oxide, for in- 

 stance N3 ; such a gas, however, is not known. 



It will be observed that these analyses do not agree among themselves 

 very nearly ; and having been prevented from making more experiments, I 

 will not venture to draw any conclusions from these results, as more analyses 

 should be made, chiefly because the apparatus with which they were per- 

 formed was somewhat defective vdth regard to the diameter of the glass 

 tubing connecting the absorbing with the measuring tube. 



Faraday was the first who observed an anomaly with nitrous oxide ; his 

 results were very uncertain as to the pressure of its saturated vapour. At a 

 temperature of 0° F. this pressure amounted to 19-05 atmospheres when 

 working from lower to higher temperatures ; but after waiting a day he found 

 24-40 atmospheres, consequently a difterence of 5-35 atmospheres. This dis- 

 crepancy he ascribed to the gas being a mixture of two different bodies solu- 

 ble in each other but differing in the elasticity of their vapour. 



Stefan (Sitzungsber. der K. Akademie der Wissenschaften zu Wien, Bd. Ixxii. 

 1875), in his researches on heat-conduction of gases, also found the nitrous 

 oxide mixed with another gas. He says, " Von diesem Gase wurde vor dem 

 Abschlusse der Durchleitung durch den Apparat eine Probe in einer Absorp- 

 tionsrohr iiber "Wasser aufgefangen. Nach zwei Tagen war das Gas bis auf 

 cinen etwas iiber 10 Procent des urspriinglichen Volumens betragenden 

 Biickatand (Stickstoff) verschwunden." 



