34^ On the conjl'ituent Parts of Azot. 



not, as hitherto beheved, a mixture of oxygen gas and azotic 

 gas, but rather a mixture of oxygen gas and hydrogen, and, 

 if I may be allowed the expreffion, water in the form of gas. 

 When by chemical experiments, which very improperly have 

 been called eudiometric, the oxygen is feparated from the hy- 

 drogen, this feparation never can be efle6led entirely or com- 

 pletely: a part of the oxygen remains united to the hydrogen, 

 and forms that chemical combination which we call azot, and 

 which we obtain by the above experinients. Oxygen, fo in- 

 difpenlably necelTary for fupporting the life of organifed be- 

 ings, is, by its combination with hydrogen, converted into 

 azot, which not only is unfit for maintaining life, but is a 

 real poifon, on account of the affinity it has for oxygen, and 

 the avidity with which it takes it from organifed bodies. 



Oxygen has fo great an affinity for hydrogen, when both 

 are found mixed in the atmofphere, that it is very difficult to 

 feparate them entirely : for this reafon, the analyfis of azot 

 has been attended with great trouble. When charcoal, ful- 

 phur, a taper, and metals, ceafe to burn in atmofpheric air, 

 and when animals expire in it, it ftill contains a pretty large 

 portion of oxygen. Phofphorus burns in it exceedingly well, 

 and for a very long time j and even when phofphorus ceafes 

 to burn there always remains a fmall quantity of oxygen 

 united to the hydrogen ; that is to fay, there flill remains 

 azot. Atmofpheric air, however, as I have feveral times ob- 

 ferved, may be deprived of almoft all its oxygen, and the 

 analyfis of it may be rendered almoft complete, by heating 

 phofphorus in it for fome time. Phofphorated hydrogen gas 

 will then be obtained by the convgrfion of a part of the azot 

 into hydrogen. 



It refults from thefe experiments, that eudiometry, fuch as 

 it exifts at prefent, is founded on erroneous principles. The 

 azot obtained by thefe experiments being always a produ6t 

 of the operation, and not having previoufly exifted under the 

 form of azot in the air fubjefted to examination. Von Hum- 

 toldt, who is fond of drawing general conclufions from indi- 

 vidual fafts, feems to have been deceived when he aflJerts, 

 Jba^ garths might be employed tp determine the quantity of 



