104 Mr Graham on Phosphuretted Hydrogen. 



10. Properties of nitrous phosphuretted hydrogen. 



(1.) This gas loses its self-accendibility when kept over mer- 

 cury, in a period varying from six to twenty-four hours, accord- 

 ing to the amount of nitrous impregnation. 



It is remarkable that this gas continues, in general, inflam- 

 mable for a longer time, when confined over water, than over 

 mercury, which is the reverse of what occurs with the gas from 

 phosphuret of lime. 



( c 2.) The factitious gas is deprived of its spontaneous inflam- 

 mability by charcoal and other porous absorbents, by essential 

 oils and hydrocarburets, and by amalgam of potassium, and quite 

 as rapidly as is its natural prototype. 



(3.) Phosphorous acid, and concentrated sulphuric acid, appear 

 likewise to withdraw the nitrous principle, although phosphoric 

 acid does not. The agency of these acids probably exemplifies 

 the disposition of nitrous acid to combine with other acids. The 

 action of potassium and of essential oils upon nitrous acid, requires 

 no explanation. Potassium has, I find, no action upon pure ni- 

 tric oxide in the cold. 



(4.) A cubic inch of this gas, passed up into a receiver, of 

 which the inside was moistened with caustic alkali, had its accen- 

 dibility sensibly impaired in fifteen minutes, but not completely 

 destroyed in less than an hour. 



In conclusion, the statement of the above properties is abun- 

 dantly sufficient to prove that a strong analogy subsists between 

 our nitrous phosphuretted hydrogen and the self-accendible gas, 

 which has been so long in the hands of chemists. The peculiar 

 principle of the last may therefore possibly be an oxygenated 

 body. That principle cannot be nitrous acid, but it may be a 

 compound of phosphorus and oxygen, P, analogous to nitrous 

 acid. In all the reactions by which self-accendible phosphuretted 

 hydrogen is produced, we have the simultaneous formation of 

 compounds of phosphorus and oxygen, such as hypophosphorous 

 and phosphoric acids. The compound P is hypothetical, however, 



