152 Professor 31. 0. Forster [May 5, 



WEEKLY EVENING MEETING, 



Friday, May 5, 1911. 



SiE William Crookes, O.M. LL.D. D.Sc. F.R.S., Honorary 

 Secretary and Vice-President, in the Chair. 



Professok Maetin 0. Forster, D.Sc. Ph.D. F.Pt.S. 31. R.I. 



New Organic Gompowuls of Nitrogen. 

 [with expeeimental illustrations.] 



It may be stated without fear of contradiction that the most versatile 

 form of elemental matter is nitrogen. Rivalled only by argon and 

 its associates in reluctance to take part in chemical action, its entrance 

 into combination with other elements leads to interesting forms of 

 activity in great profusion. Union with hydrogen in different pro- 

 portions, for example, produces ammonia, hydrazine and hydrazoic 

 acid, three highly reactive substances having characteristics which 

 stand in marked contrast with one another. If oxygen be brought 

 into the system, hydroxylamine, nitrous acid and nitric acid may be 

 mentioned as typical materials capable of entering into chemical 

 changes of the most diverse order. 



Organic derivatives of nitrogen, however, present an even greater 

 display of individuality. Prussic acid, the alkaloids, nitro-glycerine, 

 gun-cotton, celluloid, artificial musk, lyddite, indigo, the azo-dyes, 

 haemoglobin and the enzymes are a few of the conspicuous nitrogen 

 compounds which suggest themselves in this connection, and a survey 

 of their activities would justify a reference to nitrogen as 



" An element so various it seems to be 

 Not one, but all Hermetic Art's epitome." 



It is not the occasion, however, to discuss the foregoing materials, 

 my present purpose being rather to deal with some new organic deri- 

 vatives of nitrogen which, although not associated with any important 

 industrial development, nevertheless display properties of considerable 

 interest to chemists. 



The extraordinary inertness of elemental nitrogen has been already 

 mentioned, and the underlying cause of this feature is the tenacity 

 with which two atoms of the substance remain in combination with 

 each other. But in circumstances which will be expLdned later, three 

 atoms of nitrogen may be brought into and maintained in combina- 

 tion, the resulting complex being known as the triazo-group. It is a 

 remarkable fact that although, as has just been seen, nitrogen is dis- 



