WESTPHAL SPECIFIC GRAVITY BALANCE
THE ANALYST'S COLUMN
with
Non-rusting,
Stainless-steel Beam end Support
Agate Bearings, Cobalite
knife-edge High
Sensitivity
Specific gravities o f liquids a r e determined
to
the
fourth
Direct
Honvitz, secretarytreasurer of the Association of Official Agricultural Chemists, writes:
zero.
The plummet, which is accurately
placement o f 5 grams of distilled w a t e r at 1 5 ° C, is then submerged in the liquid riders a r e moved along the beam
until the pointer zeros a g a i n .
The value
of the specific g r a v i t y is indicated b y the positions o f the riders on the b e a m .
No. 4 0 2 8 A . EXTRA RIDERS. Set of five, for No. 4 0 2 8 W e s l p h a l Balance. No. 4028. Complete with calibrated plummet having internal thermometer, durable hardwood storage box (not illustrated), glass cylinder, stainless-steel counterpoise, forceps, set oF five riders, and instructions. Each, S45.00
PETERSON
Each, $5.45 No. 4 0 2 8 B . EXTRA PLUMMET. For N o . 4 0 2 8 W e s t p h a l Balance.
Each, $ 9 . 8 5
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As is customary in this association, all methods and proposals are approved anil published as first action, so that all mayhave an opportunity to submit their comments, suggestions, or criticisms of any proposals pending for final adoption. The proposals in this report are particularly important at, this time, since if they are adopted at the 1954 meeting of the association, the Eighth Edition of "Official Methods of Analysis of the Association of Official Agricultural Chemists," which is scheduled for publication late in 1955, will be edited to comply with these recommendations. We would therefore be very interested in having this report on spectrophotometry called to the attention of all interested analytical chemists. . . . T h e report itself will be published in the February issue of the Journal of the Aslociation of Official Agricultural Cfiemi.iti, and reprints will be available either from the chairman of the committee, Mr. Jones, or from the office of the association on approximately March 15.
S e n d for Illustrated Catalog
FREE
LEONARD
T h e following a r e from t h e " P r e 2 6, N O . 2, F E B R U A R Y
Reading
c a l i b r a t e d t o 15 grams weight a n d dis-
and
VOLUME
place.
To use, the beam is first adjusted to
VI/~ILLIAM
About a year ago the Association of Official Agricultural Chemists appointed a committee on spectrophotometry to recommend a uniform nomenclature and methods of presentation of data for use in its publications. This committee consisted of John H. Jones and Jonas Carol of the Food and Drug Administration, W. T. Mathis, Connecticut Agricultural Experiment Station, G. M. Wyman, National Bureau of Standards, and B. A. Brice, Eastern Regional Research Laboratory of the U. S. Department of Agriculture. The committee presented its preliminary report, at the last meeting of the association, based upon the recommendations of the Joint Committee on Nomenclature in Applied Spectrophotometry published in ANALYTICAL CHEMISTRY, 24, 1349 (1952). The present report, however, was considerablyabridged, since the committee desired to formulate a system of spectrophotometry terminology as applied specifically to analytical chemistrj'.
decimal
Values up to 2 . 0 0 0 m a y be measured.
L.T. HALLETT, Science Editor
P E T E R S O N & co., INC.
1230 Fullerton Ave. 1954
Chicago 14, Illinois 13 A
