ld it be
required, add another drop of the ammonia. Repeat this until the proper
tone of color has been reached, neither red nor blue. After thus fixing
the precise point of the saturation of the acids, the burette is held
upright, and the quantity of the solution of ammonia consumed is
accurately determined,--that is, to what line on the scale the burette
has been emptied. The quantity of the solution so used corresponds with
the quantity of acids contained in the must--the larger division lines
opposite the numbers indicating the thousandths part, and the smaller
lines or dots the ten thousandths part.

"Until the eye has learned by practice to recognize the points of
saturation by the tone of color, it can be proven by means of litmus
paper. When the mixture in the bottle begins to turn blue, put in the
end of a slip of litmus paper about half an inch deep, and then draw
this end through your fingers, moistened with water. So long as the
ends of the blue litmus paper become more or less reddened, the acids
have not been completely saturated. Only when it remains blue, has the
point of saturation been reached.

"In examining _red_ must, the method should be modified as
follows:--Instead of first filling the pipette with tincture of litmus,
fill it with water to the line A, and transfer it into the bottle.
After the quantity of must has been added, drop six-thousandths of the
solution of ammonia into the mixture, constantly shaking it while
dropping, then test it, and so on, until, after every further addition
required with litmus paper, it is no longer reddened after having been
wiped off."

DR. GALL further gives the following directions, as a guide, to
distinguish and determine the proportion of acids which a must should
contain, to be still agreeable to the palate, and good:

"Chemists distinguish the acid contained in the grape as the vinous,
malic, grape, citric, tannic, gelatinous and para-citric acids. Whether
all these are contained in the must, or which of them, is of small
moment for us to know. For the practical wine-maker, it is sufficient
to know, with full certainty, that, as the grape ripens, while the
proportion of sugar increases, the quantity of acids continually
diminishes; and hence, by leaving the grapes on the vines as long as
possible, we have a double means of improving their products--the must
or wine.

"All wines, without exception, to be of good and of agreeable taste,
must contain fr