W e l c hTRANSMISSIONDENSITOMETER for QUANTITATIVE PAPER CHROMATOGRAPHY combines
ΤΤ7Έ COMMENTED editorially in the Feb» * ruary issue on the streamlined name of the "Society of Public Analysts and Other Analytical Chemists" to "The Soci ety of Analytical Chemistry." Analysis in Britain started with the demand for con trol of food and drug products, so that the public could be protected against fraud and poisoning. The same conditions in this country brought into being the food and drug laws which necessitated develop ment of adequate analytical procedures for the guidance of enforcement agencies. For those whose libraries subscribe to Food, Drug, Cosmetic Law Journal, we recommend as interesting reading an arti cle by George Taylor in the March issue, Vol. 9, page 133, dealing with the history of analytical chemistry in Britain begin ning with the formation of the Society of Public Analysts in 1874. For those who do not have the article available, we quote : Despite its name, the membership of the society was not confined to public analysts, although it was restricted t o "analysts in practice" until 1899, when it was broad ened to include persons having a bona-fide interest in analytical chemistry. But the appointment as a public analyst was the handiest of instruments for the endeavor to establish the science of analytical chem istry with particular reference to the com position of foods and their methods of analysis. Even so, the work was not omitted nor circumscribed ; the laboratory of the public analyst was often the center of activities dealing with matters of the health and amenities of the public within the pur view of the particular local authority con cerned. . . . Following the historical outbreak of ar senical poisoning in 1901—consequent on the use of arsenical glucose in a brewery which resulted in beer containing poison ous amounts of arsenic—which caused a number of deaths and many cases of seri ous illness, t h e society was associated with the Society of Chemical Industry in de vising methods of analysis. Members gave evidence before a royal commission whose final report recommended limits for arsenical contamination in foods which have been generally accepted and have been officially acted on for more than 50 years. The recent recommendations of the Ministry of Food in respect of statu tory limits. can scarcely be said to differ significantly from those earlier recommen dations. . . . In 1929 the society collaborated with the Association of British Chemical Manufac turers in recommending permissible limits for the arsenical contamination of coloring matters for foodstuffs, in 1930 with the Food Manufacturers Federation in recVOLUME
2 6, N O . 6, J U N E
1954
the DENSICHRON
with
Transmission
Light
Source
PATENT NO. 241493a
The special Welch Transmission light source with a filter paper guide for holding and advancing the papergram at 3 mm increments, when used with the Densichron becomes a complete transmission densitometer for quantitative paper chromatography. The quantitative analysis of complex compounds such as PRO TEINS, SUGARS, V I T A M I N S , etc., has been simplified by reading maximum densities of papcrgrams with the DENSICHRON. This new apparatus and procedure will speed up your work and permit the analysis of very small samples. Works equally well for quantitative paper electrophoresis. This Instrument was demonstrated last December at the Chemical Industries Exposition in Philadelphia. Write for literature describing the production of papcrgrams and the use of the Densichron for quanti tative determination by the maximum density method. $425.00
iS o i
W.
M. WELCH SCIENTIFIC
COMPANY
uf« DIVISION OF W. U. WKT,CH MANUFACTURING COMPANY &
A n i m p o r t a n t service p r o v i d e d by A N A L Y T I C A L C H E M I S T R Y is t h e R E A D E R S ' INFORMATION SERVICE section. T h i s section provides a n easy a n d simplified m e a n s for t h e r e a d e r t o o b t a i n a d d i t i o n a l i n f o r m a t i o n o n p r o d u c t s offered in t h e Advertising Pages a n d t h e New Product releases. T h e e d i t o r s believe s t r o n g l y t h a t t h i s m a t e r i a l offers t h e c h e m i s t a n d e n g i n e e r , y o u n g a n d o l d , i n f o r m a t i o n of g r e a t p r a c t i c a l v a l u e . M a n u f a c t u r e r s c o n t i n u a l l y s e n d i n for review t h e i r p r o d u c t a n n o u n c e m e n t s a n d i n d u s t r i a l l i t e r a t u r e . T h e s e a r e s c r e e n e d b y t h e ACS e d i t o r s t o m a k e s u r e t h a t t h e i n f o r m a t i o n p u b l i s h e d is r e a l l y n e w a n d c o n t a i n s v a l u a b l e scientific o r t e c h n i c a l d a t a . A d d i t i o n a l i n f o r m a t i o n c a n b e o b t a i n e d simply by m a r k i n g u p a n d mailing t h e h a n d y r e t u r n coupon or card provided. T o a s s u r e y o u r c o n t i n u e d s u c c e s s i n t h e m o s t k a l e i d o s c o p i c field, ANA L Y T I C A L C H E M I S T R Y ' S e d i t o r s s u g g e s t t h e p r a c t i c a l v a l u e of b u i l d i n g u p a r e a d y r e f e r e n c e l i b r a r y of m a n u f a c t u r e r s ' l i t e r a t u r e — t h e c o u p o n i n t h i s p u b l i c a t i o n is t h e b e s t m e a n s of d e v e l o p i n g s u c h a s o u r c e of d a t a . Y o u r R E A D E R S ' I N F O R M A T I O N S E R V I C E c o u p o n a p p e a r s o n page of t h i s i s s u e .
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