EXPERIMENT XXXIV.

Twenty drops of syrup of violets mixed with a glass-full of water were

changed into a lively red by the addition of one drop of dilute spirit

of vitriol. The season of the year did not allow us to use the fresh

juices of vegetables, but this trial shews the genuineness of the syrup

of violets, and that it was a sufficiently delicate test of acidity.

Experiments and Observations on the Following Subjects 1. On the preparation, calcination, and medicinal uses of Magnesia Alba. 2. On the solvent qualities of calcined Magnesia. 3. On the variety in the solvent powers of quick-lime, when used in different quantities. 4. On various absorbents, as promoting or retarding putrefaction. 5. On the comparative antiseptic powers of vegetable infusions prepared with lime, &c. 6. On the sweetening properties of fixed air. · 第 86 / 93 题