OF ARTS AND SCIENCES. 51 



Methyl Alcohol. 



Although a small amount of methyl alcohol was contained in the 

 hit^her fractions of (a) and (6), it was evidently condensed foi' the 

 most part in the fraction 65° - 68° of {c). This fraction was slightly 

 yellow in color, but no further attempts were made to determine its 

 purity than an estimation of the percentage of acetone, which will 

 presently be described. 



Dimethylacetal. 



The formation of dimethylacetal during the dry distillation of wood 

 for the preparation of methyl alcohol was not observed until 1864, 

 probably because of the small difference between its boiling point (64°) 

 and that of methyl alcohol. After removing the methyl alcohol and 

 acetone, Dancer* succeeded in separating a product which proved to be 

 identical with dimethylacetal, made by heating methyl alcohol with 

 acetic aldehyde. Kramer and Grodzkyf state that it has since been 

 recognized as a constant constituent of wood spirit. Its formation is 

 probably due to the high temperature of the distillation, which enables 

 the aldehyde to act upon the methyl alcohol. From the large per- 

 centage of aldehyde in the product under consideration, it would seem 

 that this reaction had not taken place to any extent. Since an exami- 

 nation of the distillate below 65° in (c) failed to reveal the presence 

 of dimethylacetal, a second portion of 2,000 grms. was fractioned, the 

 lower fraction saponified and distilled over calcic oxide. The small 

 amount of residue left after removing the methyl alcohol with calcic 

 chloride, distilled at 57° -58°, was readily miscible with water, and 

 its reactions in general were characteristic of acetone. Dimethyl- 

 acetal could not therefore have been formed in quantity sufficient 

 for identification. 



Acetone. 



The first quantitative experiments on the influence of acetone upon 

 the commercial value of methyl alcohol were made by Kramer and 

 Grodzky.l They determined the quantity of dimethylaniline which 

 could be obtained from a given weight of pure methyl alcohol, and also 



* Ann. Chem. Pharm., cxxxii. 240. 



t Berichte deutsch. chem. Gesellscli., 1876, 1920. 



X Ibid., 1880, 1005. 



