OP ARTS AND SCIENCES. 49 



The residue of the distillation in each case contained the greater 

 part of the water, though in (a) it consisted chiefly of methyl alcohol. 

 In (b) approximately one half of the residue consisted of ihe higher 

 boiling oils, and in (c) it was composed beside water of furfurol and an 

 oil of low specific gravity. The constituents of the various fractions 

 will be described in detail. 



Acetic Aldehyde. 



In (a) the fraction that came over between 20° and 25° was very 

 soluble in water, and it gave the penetrating odor characteristic of 

 acetic aldehyde. This substance was also recognized in that portion 

 of (b) which distilled below 54°, and in the fraction below 63° in (c). 

 It formed a compound with acid sodic sulphite, crystallizing in 

 flat prisms, which were very soluble in water. In order to estab- 

 lish its identity, an aqueous solution of the fraction 20° - 25° was 

 boiled with an excess of silver oxide, filtered, and concentrated by 

 evaporation. On cooling, silver acetate crystallized in characteristic 

 forms, which, on analysis, gave the required percentage of silver. 



I. 0.2222 grm. of the substance gave on ignition 0.1432 grm. Ag. 

 II. 0.3167 grm. of the substance gave on ignition 0.2050 grm. Ag. 



Ag 



According to Kramer and Grodzky,* in the manufacture of wood 

 spirit acetic aldehyde may usually be found in the first portions of the 

 distillate. It is rarely present in large quantities, since, as they assert, 

 the greater part is converted into dimetbylacetal during the distillation. 



Methyl Formiate. 



This substance was isolated from the fractions 25° - 30° and 30° - 40°. 

 On the addition of water an oil separated, which was purified by frac- 

 tional distillation. There were thus obtained 8 grms. of a substance 

 which distilled between 30° and 35°. It was saponified by boiling 

 with an excess of plumbic hydrate, and the composition of the plumbic 

 formiate determined by analysis. 



* Berichte deutsch. chem. Gesellsch., 1876, 1920. 

 VOL. xviii. (n. 8. X.) 4 



