THE PURITY OF GLYCERIN. 



By L. F. KEBLER and H. C. FULLER. 

 SCOPE OF INVESTIGATION. 



The question of the purity of glycerin has assumed great impor- 

 tance during recent years because of the extensive use of this product 

 in the preparation of medicinal agents. This has been impressed on 

 the manufacturers to such an extent that the quality of glycerin on 

 the market has been greatly improved and the best grades may now 

 be procured without difficulty. 



The claim has often been advanced that the present glycerin 

 standard is too rigid and in certain respects can rarely be attained; 

 hence the Pharmacopreia should be so modified that it will be con- 

 sistent with conditions which actually exist. To confirm or refute 

 this statement it was necessary to investigate the quality of the 

 glycerin on the market in the United States, and to determine exactly 

 to what extent samples from different sources conformed to the tests 

 prescribed in the Pharmacopoeia. Another purpose was to learn 

 whether there were any glycerins which would not reduce Fehling's 

 solution, the claim that no such article was obtainable being of impor- 

 tance owing to the use of glycerin in the preparation of Haines's 

 solution, an alkaline copper liquid which has been recommended for 

 detecting sugar in urine and whose value as a testing reagent would 

 naturally be impaired if reduction occurred when no sugar was 

 .present. 



Letters were sent to manufacturers in different parts of the country 

 requesting samples, the scope of the inquiry being outlined suffi- 

 ciently to give them every opportunity to submit glycerin of as high 

 quality as possible, together with any comments and suggestions 

 deemed desirable. When the examination had been completed, the 

 several dealers who had responded were sent analyses of their own 

 makes of glycerin, with a request for further criticisms before the 

 publication of the results. Samples were received from the following 

 11 firms in the United States, two additional samples of foreign 

 manufacture having been purchased on the open market: 



Armour Soap Works, Chicago (two samples). 

 Colgate & Co., New York. 



Harshaw, Fuller & Goodwin Co., Cleveland, Ohio. 

 Wm. A. Jobbins, Aurora, 111. 

 Jas. S. Kirk & Co., Chicago. 

 Larkin Co., Buffalo, N. Y. (two samples). 

 Marx & Rawolle, New York. 



Peet Bros. Manufacturing Co., Kansas City, Kans. 

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