1856.] the Chemical Type: Ammonia. 277 



The modern progress of Organic Chemistry has removed those 

 difficulties. 



Organic Cliemistry deals with compound molecules, consisting 

 of carbon and hydrogen, occasionally associated with nitrogen 

 and oxygen. These compound molecules, often called compound 

 radicals, simulate the deportment and exercise the functions of 

 elementary substances. One of the most familiar illustrations of 

 organic radicals is the radical Ethyl, consisting of four equivalents 

 of carbon, and five of hydrogen, C4H5 = E, and which chemists 

 assume to exist in alcohol and ether, the derivation of which from 

 water becomes obvious by a glance at the following formulae : — 



Water .... {|{0 

 Alcohol . . . . \y\r\ 

 Ether .... {|g 



Alcohol may be regarded as water, in which one equivalent of 

 hydrogen is replaced by ethyl, ether, as water, for the two hydro- 

 gen-equivalents of which ethyl has been substituted. The general 

 characters of these three compounds greatly differ from one 

 another; but some of the fundamental properties of water, ils 

 neutral character for instance, are retained in the two substitution- 

 products.* 



Recent researches have proved that in ammonia likewise the 

 hydrogen-equivalents are replaceable by ethyl. Three new com- 

 pounds are thus produced, which have received the names ethyla- 



manufacture of ammoniacal salts was, moreover, illustrated by a series of painted 

 diagrams, and a set of large and beautiful specimens furnished by Messrs. Simp- 

 son, Maule, and Nicholson, Kensington. Ammonia was evolved by the action of 

 lime upon sal-ammoniac, phosphoretted hydrogen by that of hydrochloric acid 

 upon phosphide of calcium, antimonetted and arsenetted hydrogen lastly, by 

 introducing antimony- and arsenic-solutions into flasks from which hydrogen was 

 l)eing evolved. Cylinders were filled with the four gases over mercury. The 

 phosphoretted hydrogen evolved proved to be spontaneously inflammable. 

 Antimonetted and arsenetted hydrogen were inflamed by a taper, and am- 

 monia was shown to be capable of combustion by directing the current of the 

 gas through a gas-flame. It was demonstrated that phosphoretted, antimonetted, 

 and arsenetted hydrogens are not absorbed by water or even acids, and that 

 they exhibit no alkaline reaction with vegetable colour's; whilst ammonia is 

 absorbed by water and acids, and possesses the character of a strong alkali. 



* Specimens of water, alcohol, and ether placed in juxta-position. Ethyl- 

 gas, obtained by the action of zinc upon the iodide of ethyl in a strong copper 

 digestor, exhibited and burnt. 



