This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
Our own process of preparing vanilla extract or tincture is somewhat modified; we use no sugar, and employ diluted alcohol. Slice one pound of the vanilla bean, and cut in small fragrants. Then macerate for ten days with five pints of equal parts of alcohol 95° and water, draw off and filter. Where much material is operated on, the extraction is preferably accomplished by the procedure of re-maceration. When tonka is conjointly used the operation need not be varied, as its relation to the menstruum is even more favorable than that of vanilla. The crude material may be exhausted with diluted alcohol, separately or coincidently. Their combined ex-tracton is, as a rule, more convenient.