Page:Treatise on Soap Making.djvu/67

51 No 16, in that case the ley is $16⁄128$ parts heavier than water, or 8 drams, reasonably supposed to be alkaline salt.

Notwithstanding that various sorts of alkali are enumerated, it is supposed that there is but one alkaline principle in nature, which, by being variously combined with sundry substances, assumes various particular properties. However, an alkali is never found pure in nature, but it is always combined with other substances, from which it must be separated by art, in order to obtain it sufficiently pure. The fixed alkali is obtained either from sea-salt, or from vegetables; hence it is called fixed mineral alkali in the first case, and fixed vegetable alkali in the second.

Having in the foregoing pages endeavoured to furnish the attentive reader with a tolerable idea of the preliminaries of soap-making, we shall now proceed to what I consider the