94= Gerhard? s Organic Chemistry. 



C „ H , ; Berzelius as the bin-oxyd of C 4 H 6 , and Zeise as a hy- 

 druret of C 4 H s O 3 . The inconvenience of this system arises not 

 only from the fact that the radicals are hypothetical, but that 

 their very existence in the compounds is alternately claimed and 

 denied, and the elements are arranged and re-arranged like the 

 letters in an anagram, as the case may require. M. Liebig seems 

 to have felt its deficiencies, for after describing in the first vol- 

 ume of his Traite, a number of bodies as derivatives of compound 

 radicals, in the succeeding portions of the work he returns to the 

 old divisions of acids, alkalies, essential oils, etc. 



This mode of viewing organic compounds resulted from the 

 idea of dualism in chemical compositions, which had found advo- 

 cates m the great majority of chemists since the days of Lavoisier, 

 and has been perpetuated by the received system of nomenclature. 

 And although there have been at different times those who have 



, * 1 "1 • nr% % . • •» - . 



difficulties 



has gained partisans.* This 

 as that of the French school and 



. ~ JVWW xo ^xoLxiiguioiicu as iiicii oi ine rrencn scnooi, aim 



ranks among its adherents the most distinguished chemists of 

 trance. It rejects entirely the idea of a binary arrangement in 

 the composition of bodies, and regards their atoms as constituting 

 a system, m which one or more molecules may be exchanged for 



arrangement. 



type 



M. Gerhardt, who has been long known as one of the most 

 distinguished chemists of France, has attempted the task of sys- 

 tematizing the great accumulation of facts which organic chem- 

 istry presents, and framing a classification that shall embrace all 

 tnose substances whose composition is accurately determined, 

 and in the present work he has given us the result of his labors. 



Kesearches in organic chemistry have shown that we can pro- 

 duce artificially many products of the vegetable and animal or- 

 ganisms. Thus sugar yields by different processes, butyric, oxa- 

 lic and formic acids ; the first of these is one of the acids of 

 butter, the second exists in the fluids of many plants, the last is 

 a secretion of ants. Again bee's wax, when fused with caustic 



forms 



acti 



, 7 J -~»*-.xj w XAUAXXXI-TV^X KJL lit; W KsVJLlXjJVM g 



among which is succinic acid, which exists in amber. These . 



products are less complex in their constitution than the original ( 



substances ; sugar by the action of oxydizing agents yields, be- I 



sides formic acid, carbonic acid gas and water, and wax when I 



converted into succinic acid, undergoes a similar decomposition. I 



nh* ^ r , J ' D Whelpley attempted some years since, to show from the electro- I 



-nem.cal decomposition of the metallic salts of the mineral acids, that they m" st I 



ue regarded I not as binary compounds of an acid with an oxyd, but as ternary com- I 



bv him"l k * m Jf tal ' ox yS en > anfl the other element. This principle was made I 



y mm we basis of a beautiful and ingenious classification of all saline compounds. I 



