304< Royal Institution : — 



This synthesis by series was an incomplete synthesis, there was a 

 gap requiring to be filled up, in order that the regular march might 

 be made up the vinic series. 



From the foregoing, it will be seen that by the year 1854 very 

 considerable progress had been made in the building up of organic 

 bodies from their ultimate elements. 



We now pass on to the consideration of the period comprising 

 the last ten years, from 1854 up to the present time. 



During this period we have had new methods of accomplishing 

 some of the syntheses which had been effected previously. Thus 

 formic acid, which, as we have seen, had been formed from inorganic 

 materials so long ago as 1831, was built up by Berthelot by means 

 of carbonic oxide and caustic potash, 



CO + KHO = CHK0 2 , 



and again by Kolbe by using carbonic acid, moisture, and sodium 

 (the moisture and sodium giving nascent hydrogen), 



C0 2 + H+Na=CHNa0 2 . 



Again, also, the passage from an alcohol to the next higher acid 

 was repeated. Carbonic acid and a compound of an alcohol radical 

 with an alkali-metal coalesced and formed a salt of a fatty acid, 

 thus : — 



C0 2 + NaC 2 H 5 =C 3 H 5 NaO 2 * 



Sodium- Propionate 

 ethyle. of soda. 



Still these reactions, however interesting they might be, were not 

 new syntheses ; they were only new methods of effecting old syn- 

 theses. 



The great problem, how to step from one alcohol to that next 

 above it, has received a general solution from Mendius. Mendius 

 used cyanogen compounds — those hydrocyanic ethers which had 

 already done such good service to organic synthesis — and exposed 

 them to the action of nascent hydrogen, and so obtained amides of 

 alcohol radicals higher than the alcohol radicals started from. The 

 reaction bears a close similarity to the one which takes place 

 between the cyanides and alcoholic solution of potash, and which, 

 as will be remembered, enabled us to pass from the alcohol to 

 the acid next above. 



Here is a scheme to show the parallel : — 



Transformation to Amide. 



fir f n H" 



ivl N iv J H 



L c H Lc 2 H 5 



* The experiment was shown ; and the great evolution of heat which 

 took place on bringing carbonic acid into contact with sodium-ethyle was 

 apparent. 



