This agent, although used very extensively in preserving meats, vegetables, and canned goods, does not seem to have been applied to malt liquors to any great extent, although it has been found in wines. Its use is prohibited in France and Germany. The test for boracic acid is best applied to the ash. If this is rubbed up with water acidulated with a little hydrochloric acid and a piece of turmeric paper dipped into the solution and then dried, it will show a peculiar reddish tint if borax be present. For a very delicate test a large quantity of the liquid to be tested may be evaporated to a sirup, with a slight addition of sulphuric acid, the residue extracted with alcohol, and the latter ignited. The edges of the flame will be colored green if borax is present. None of the samples examined gave any test for borax.

In conclusion of the work on preservatives, it may be noted that it was done during the cold weather of January, February, and March. It is quite probable that during warm weather the use of preservative agents is still more general than shown by the analyses.