THE WELCH SCIENTIFIC COMPANY

Page 1 ... tion, but seemingly no one company uses a logical, consistent system. For example, Schleicher and Schuell in order of ... similar plan. Pap...
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THE EDITOR'S COLUMN /

C O M E TIME AGO we received a let-

ter from a university professor commenting on t h e lack of standardization in filter paper nomenclature. H i s letter read in p a r t as follows: Much work has been done toward standardization in chemistry: nomenclature of chemicals, standard taper joints, etc. However, there is one need yet, the need for a standard system of filter paper nomenclature. Various manufacturers not only do not use the same system of designation, but seemingly no one company uses a logical, consistent system. For example, Schleicher and Schuell in order of increasing coarseness, has numbers 507, 590, 589 (various colored ''ribbons'*), and 589-1 H. In the same order are Whatman 42, 44, 40, 41, and 41-H. Munkigill uses OK and 0 0 . The qualitative''papers listed are just as confusing. S&S papers, in order of increasing coarseness, are 576, 402, 602, 596, 497, 597, etc.; Whatman in the same order are 50, 32, 5, 52, 30, 2, 1, 3, etc.; while Munktell are 100, OB, IF, 2, 3, 0. I t is a small but definite and useless, nuisance. Speaking from the viewpoint of the chemist, having talked with many of them, I believe that a survey of users would show virtual unanimity in favor of a standardized nomenclature. A suggested standard system might be with numbers 500 to 599, finest to coarsest, for quantitative papers, and 400 to 499 for qualitative, or some similar plan. Papers now manufactured could be given appropriate numbers in the series, with letter suffixes for special treatment, as H for hardened, A for acid-washed, etc. Each manufacturer feels that his product is unique. However, I have never had any detectable bad effects from changing brands. I do agree that a numbering system should be used in connection with, rather than as a substitute for, trade names and numbering systems, possibly being placed in parentheses after the usual designation. There is more than a little wishful thinking in the idea that users of different papers are familiar with the designations of different manufacturers. The familiar charts are often consulted. The use of government specification symbols would be rather unwieldy, if past experience serves.

L T. Hallett,

There is no question that setting up the system would be a hard and involved process. I believe this to be an excellent opportunity for some work by a good committee. W e did n o t know whether a standard system of filter paper n o menclature was desirable, or if d e sirable, whether it was feasible. I t is our feeling, however, t h a t m a n y chemists have considered this m a t t e r a n d have wondered w h y some s t a n d a r d system was n o t adopted. T o ascertain t h e reasons, we, therefore, polled t h e major manufacturers and distributors for their comments and opinions. T h e y were asked whether their classification system h a d a n y significance; whether they favored a s t a n d a r d system, a n d if so what form it might t a k e (in this regard

IVelcll

Editor

the proposal of a four digit number to indicate qualitative or q u a n t i t a tive papers, t y p e of material, t y p e of surface, flow rate, etc., was presented) ; whether a standard system might be used in conjunction with their existing system and thus protect existing t r a d e names or numbering systems ; and what group might be best qualified t o develop a s t a n d a r d system (National B u reau of Standards, A S T M , or ACS, for example). Results

There is no clear cut agreement between either manufacturers or dealers as to t h e desirability or need for a s t a n d a r d classification system. Some in each category favor t h e idea while others oppose.

C r y s t a l Lattice a n d M o l e c u l a r M o d e l Kit

Illustrated

Set has

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54 foam-

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spheres plus connectors

Paradichlorobenzene Crystal lattice of Sodium Chloride

Difference between covalent and ionic bonding may be shown. Crystal Lattice and Molecular Model Kit Cat. No. 5739 Each $27.50 Ses our exhibit at Booffr 95—Hal'l Inst, of Health, Ocf. 10-13. 7967

Bethesda—

THE WELCH SCIENTIFIC COMPANY ESTABLISHED 1880 1515 Sedawiclc Street, Dept. A - 1 , Chicaao 10, Illinois, U. S. A .

VOL. 33, NO. 10, SEPTEMBER 1961



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