II. Note on the separation of the isomeric amylic alcohols formed by fermentation

At present we are acquainted with two amylic alcohols formed by fermentation. They were discovered by Pasteur, who observed that different specimens of amylic alcohol caused a ray of polarized light to rotate to different degrees. He succeeded in devising a separation of these alcohols, which consisted in converting them into sulphamylates of barium and recrystallizing these salts. The one alcohol is without action on polarized light, and the other rotates it. This method of separation is beset with great practical difficulties, and has, we believe, only once been repeated, viz. by Mr. Pedler. He gives no detailed account of the separation, but gives some of the leading properties of the alcohols. He found that the rotating alcohol caused a ray of polarized light to rotate 17° with a column of 500 millims. of liquid. The following are some examples of the rotations effected by eleven different samples of amylic alcohol in a column of 385 millims. For comparison with Pedler’s number, the observed numbers have been reduced in the second column to observations on 500 millims.