General Account of the Nitrous Oxide. ' 285 



becomes converted into nitrous acid, and a gas analogous to atmofphertc air, but con- 

 taining a little lefs oxigen.* 



The nitrous acid formed in this procefs is very fmall in quantity, but the unabforbaWe 

 gas equals about ,8 of the original volume of the nitrous oxide. -'' ^^■^' ' '^s'-* 



V. On the Decompofttion of Nitrous Oxide hy Comhflihle Bodies. 



Se£l:. I. The changes produced in nitrous oxide by heat, are probably intimately con- 

 nected with the phenomena of its decompofition by the inflammable bodies, which in 

 general require, for their combuftion in this gas, much higher temperatures than thofe at 

 which they burn in atmofpheric air or oxigen. When they are intenfely heated, they a£t 

 upon it, and become oxigenated, nitrogen being evolved, and much heat and light generated. 



During the combuftion of folid and fluid bodies producing flame in nitrous oxide,, 

 nitrous acid is formed, moft likely in confequence of a new arrangement of principles pro- 

 duced by the ignition of a part of the gas not in eontaft with the burning fubftance. 

 Likewife when nitrous oxide ia excefs is decompofed by inflammable gafes, nitrous acidj 

 nitrogen, and a little oxigen, are produced, probably from the fame caufe. 



a. Pyrophorus, which inflames in nitrous gas and in atmofpheric air, at or even below 

 40", Fahrenheit, requires for its combuftion in nitrous oxide a temperature nearly equal to 

 that of ignition. 



b. Phofphorus may be f-ufed and even fublimed in nitrous oxide without efi^eding any 

 change in it ; but when it is introduced into it in a ftate of adlive inflammation, it burns 

 with intenfely vivid light. 



c. Sulphur does not ail in nitrous oxide when introduced into it, burning with the 

 feeble blue flame ; but if in a ftate of vivid inflammation, it decompofes it with the pro- 

 du£lion of a beautiful rofe*coloured light. 



d. Iron and charcoal, when heated white, burn in nitrous oxide with much greater 

 vlvidnefs than in the atmofpherc. 



e. The lighted taper, introduced into nitrous oxide, burns at firft as in oxigen ; but 

 afterwards with a flame, white in the centre, and blue at the circumference ; a pheno- 

 menon apparently depending upon the nitrous acid formed in the procefs. 



f. Hidrogen, and the compound inflammable gafes, when mingled in certain propor- 

 tions with nitrous oxide, and a£ted on by the eledtric fpark, explode, with the produdtion 

 of much light and heat. + 



* Dr. Prieftley firli obferved, that nitrons oxide, after being- afted upon by the eleftric fpark, became im- 

 mifcible with water; but he dfd not notice the nitrous acid produced in the procefs : neither did the Dutcfar. 

 chcmifts, who repeated his experiments. 



•fc The Society of. Chemifts at Amfterdam thought that hidrogen was the only body capable of dficom- 

 pofing nitrous oxide. Journal de Phyfique, torn. XLIII. p:\rtll. page 331. From their experiments itf 

 appears probable that in many cafes they did not raife the tempwatures of other inflammable bodies 'fuffi- 

 (yeiuly high for this purpofe. 



Sea:l. 



