59 



expected from the far distant scientific investigations of the future. 

 Here then we find ourselves face to face with one of the many questions 

 to which scientists must answer, We don't know yet. Perhaps the 

 activity and functions of nitrogen may bye and bye be located else- 

 where in the body, and it is not impossible that it may have a closer 

 connection with the nervous system than is now generally supposed. 

 But what we are now quite certain of is that comparatively little of the 

 nitrogenous substances or proteids of the vegetable kingdom remain 

 permanently in the bodies of animals. A much larger quantity, or 

 rather of their nitrogen, is made use of in simply sustaining the vital 

 processes. Ot the albuminoids thus consumed, say by the live stock 

 on a farm, their carbon finds its way to the lungs in the shape of 

 carbonic acid and their nitrogen is expelled chiefly in the liquid manure 

 of the animals. This is a fact not yet sufficiently appreciated by our 

 agriculturists generally, and much of the nitrogen thus expelled finds 

 its way back to the atmosphere. When it is properly cared for by the 

 farmer it does, or should, not escape from the soil of his fields. Our 

 nitrogen thus travels back to soil or atmosphere after having completed 

 its life giving circulation through the vegetable and animal kingdom. If 

 it is allowed to reach the atmosphere then the agency of the legum- 

 inosae is required to recapture it. If it again becomes a part of mother 

 earth it is pretty securely held and is subject to some changes which 

 we have now to consider 



Animal matter containing nitrogen, when it finds itself in a 

 soil which is destitute of bases such as potash, soda or lime, usually 

 gives rise to the formation of ammonia, but when bases are also present 

 further oxidation takes place to nitric acid with simultaneous forma- 

 tion of nitrates such as saltpetre. It was this fact which caused 

 Chaptal to suggest nitrogen as a name for that element from words 

 signifying "I give rise to nitre." 



(Here the following experiments were introduced and explanations 

 given ; combustion of phosphorus and carbon in nitrous oxide ; oxida- 

 tion of nitric oxide to nitrogen tetroxide ; production of nitric acid 

 from saltpetre. The lecturer also referred to the oxidation of nitrogen 

 in the soil, and the manufacture of nitre in the the East Indies.) 



The instability of the compounds of nitrogen has been referred to, 



