The invaders who have most affected the Berber race are the Arabs, but the two races, with a common religion, often a common government, with the same tribal groupings, have failed to amalgamate to any great extent.
Constitution of the Diazo Compounds.-P. Griess (Ann., 1866, 137, p. 39) considered that the diazocompounds wereformed by theaddition of complex groupings of the type C 6 H 4 N 2 - to the inorganic acids; whilst A.
The aldo-ketenes are colourless compounds which are not capable of autoxidation, are polymerized by pyridine or quinoline, and are inert towards compounds containing the groupings C :N and C :O.
It is well known that singly, doubly and trebly linked carbon atoms affect the physical properties of substances, such as the refractive index, specific volume, and the heat of combustion; and by determining these constants for many substances, fairly definite values can be assigned to these groupings.
those containing the groupings CH 2 NO 2 and >CH NO 2) form metallic derivatives; for example, sodium salts, which according to A.