en
well gummed so that no penumbra has been produced upon the edge of the
letters, a perfectly sharp image will be instantly obtained. The
excess of iodine is removed by washing with alcohol and water, and the
leaf is then dried and preserved between the leaves of a book.

It is well before decolorizing the leaf to immerse it in a solution of
potassa; the chlorophylian starch then swells and success is rendered
easier.--_Lartigue and Malpeaux, in La Nature_.

* * * * *

STANDARDS AND METHODS FOR THE POLARIMETRIC ESTIMATION OF SUGARS.[1]

[Footnote 1: Report to the United States Internal Revenue Department
by C.A. Crampton, Chemist of U.S. Internal Revenue; H.W. Wiley, Chief
Chemist of U.S. Department of Agriculture; and O.H. Tittmann,
Assistant in Charge of Weights and Measures, U.S. Coast and Geodetic
Survey.]

Section 1, paragraph 231, of the act entitled "An act to reduce
revenue and equalize duties on imports and for other purposes,"
approved October 1, 1890, provides:

"231. That on and after July 1, eighteen hundred and ninety-one, and
until July 1, nineteen hundred and five, there shall be paid, from any
moneys in the Treasury not otherwise appropriated, under the
provisions of section three thousand six hundred and eighty-nine of
the Revised Statutes, to the producer of sugar testing not less than
ninety degrees by the polariscope, from beets, sorghum, or sugar cane
grown within the United States, or from maple sap produced within the
United States, a bounty of two cents per pound; and upon such sugar
testing less than ninety degrees by the polariscope, and not less than
eighty degrees, a bounty of one and three-fourth cents per pound,
under such rules and regulations as the Commissioner of Internal
Revenue, with the approval of the Secretary of the Treasury, shall
prescribe."

It is the opinion of this Commission that the expression "testing ...
degrees by the polariscope," used with reference to sugar in the act,
is to be considered as meaning the percentage of pure sucrose the
sugar contains, as ascertained by polarimetric estimation.

It is evident that a high degree of accuracy is necessary in the
examination of sugars by the Bureau of Internal Revenue, under the
provisions of this act, inasmuch as the difference of one-tenth of one
per cent. in the amount of sucrose contained in a sugar may, if it is
on the border line of 80 deg., decide whether the producer