leting the clarification, precipitating excess of lead,
and facilitating filtration. In many cases of high grade sugars,
especially beet sugars, the use of alumina alone will be sufficient
for clarification without the previous addition of subacetate of lead.

[Footnote 2: Prepared as follows: Shake up powdered commercial
alum with water at ordinary temperature until a saturated
solution is obtained. Set aside a little of the solution, and to
the residue add ammonia, little by little, stirring between
additions, until the mixture is alkaline to litmus paper. Then
drop in additions of the portion left aside, until the mixture
is just acid to litmus paper. By this procedure a cream of
aluminum hydroxide is obtained suspended in a solution of
ammonium sulphate, the presence of which is not at all
detrimental for sugar work when added after subacetate of lead,
the ammonium sulphate precipitating whatever excess of lead may
be present.]

The solution is now made up to the mark by the addition of distilled
water in the following manner. The flask, grasped by the neck between
the thumb and finger, is held before the operator in an upright
position, so that the mark is at the level of the eye, and distilled
water is added drop by drop from a siphon bottle or wash bottle, until
the lowest point of the curve or meniscus formed by the surface of the
liquid just touches the mark. If bubbles hinder the operation, they
may be broken up by adding a single drop of ether, or a spray from an
ether atomizer, before making up to the mark. The mouth of the flask
is now tightly closed with the thumb, and the contents of the flask
are thoroughly mixed by turning and shaking. The entire solution is
now poured upon the filter, using for this purpose a funnel large
enough to contain all the 100 c.c. at once, and a watch glass is
placed over the funnel during filtration to prevent a concentration of
the solution by evaporation.

The funnel and vessel used to receive the filtrate must be perfectly
dry. The first portion of the filtrate, about 20 to 30 c.c., should be
rejected entirely, as its concentration may be affected by a previous
hygroscopic moisture content of the filter paper. It may also be
necessary to return subsequent portions to the filter until the liquid
passes through perfectly clear.

If a satisfactory clarification has not been obtained, the entire
operation must be repeated, s