CHEMISTRY. 187 



3. That the fixed acids are principally acids having a greater 

 atomicity than basicity, and tliey wore originally produced as 

 sodium salts, in which both the basic and typical hydrogen of the 

 acid are replaced by sodium. 



THE ARTIFICIAL FORMATION OF ORGANIC SUBSTANCES. 



Mr. C. Greville Williams made a communication to the Royal 

 Institution, which is published in their " Proceedings" for May, 

 1868, on the above subject. After defining and illustrating the 

 two great engines of chemical research, anal3'sis and synthesis, 

 he proceeded to show that all attempts hitherto made to separate 

 chemistry into two distinct branches, organic and inorganic, had 

 failed, and to argue that chemistry was "one and indivisible." 

 The grand problem, which consisted in taking the chemical ele- 

 ments themselves, and building them up gradatim into the proxi- 

 mate principles existing in the tissues of plants and animals, until 

 lately appeared almost hopeless. This apparent difficulty was 

 shown to arise from the mistake of supposing the proximate prin- 

 ciples of animals and vegetables to result from an occult power 

 vaguely termed the " vital force." He maintained that whenever 

 the proper reagents were made to act upon each other under the 

 proper conditions, the same substances were produced which at 

 one time were supposed to require the aid of vitality for their 

 formation. 



He then proceeded to enumerate some of the principal instances 

 where substances originally derived from animals or vegetables 

 had been formed synthetically. Wohler's synthesis of urea was 

 shown to be one of the earliest in point of date, and his method 

 was described, and also Kolbe's new process by the mere heating 

 of ammoniac carbonate to a point just below that at which urea is 

 decomposed. Other steps in the history of synthesis were shown 

 to be : the conversion of carbonic disulphide into carbonic tetra- 

 chloride or perchlorinated marsh gas, the former being a purely 

 inorganic body ; the production of acetic acid from carbonic d»i- 

 sulphide, or one of the most marked of the so-called organic acids 

 from purely inorganic materials ; the synthesis of oxalic acid by 

 the direct union of carbonic anhydride with sodium, as accom- 

 plished by Dr. Drechsel. As oxalic acid, by mere distillation, 

 yields formic acid, the synthesis of the first leads directly to a new 

 synthesis of the second. 



He then showed how complex bodies, hitherto obtained from 

 animal and vegetable sources, can be built up from elemental 

 carbon and hydrogen. If carbon can only be made to combine 

 directly with hydrogen, no matter how simple the resulting com- 

 pound ma)^ be, it becomes possible to cff'ect the synthesis of a vast 

 number of the most characteristic substances found in animals 

 and vegetables. This result has been accomplished through the 

 agency of acetylene, a most remarkable hydrocarbon first noticed 

 by Edmund Davy in 1836. 



He showed how acetylene can be formed from inorganic mate- 



