18 The Bulletin. 



Analysis of Samples. 



Each one of the samples reported in this bulletin was subjected 

 to a chemical and microscopical analysis to determine as far as pos- 

 sible the ingredients of which they are composed. 



Microscopical Analysis. 



In the microscopical analysis the base material or diluent is first 

 determined. This is usually a simple matter as the diluent is present 

 in such large amount that its nature is evident without examination. 

 The microscopical analysis is the only accurate means of detecting 

 the vegetable drugs used in compounding these preparations. As 

 has been seen from the list of drugs the number of vegetable drugs 

 which may be used is very extensive, and consequently the accurate 

 analysis requires a very detailed study of each sample, and an accu- 

 rate knowledge of the histological structure of the medicinal plants 

 which may be used. A great many of the drugs used possess certain 

 histological characteristics which makes their identification positive. 

 But, with some there is no characteristic element and consequently the 

 indentification can not be so positive. In all cases of identifying 

 drugs the microscopic slide made from the sample has been com- 

 pared with a slide made from a known powder of the drug in ques- 

 tion, so as to verify each identification as completely as possible. It 

 is not claimed that the microscopic analysis as reported in this bulle- 

 tin includes all the drugs used in each preparation, for some of them 

 are used in very minute quantities, but it is believed that each analy- 

 sis is so complete that it includes all of the drugs present in suffici- 

 ent amount to have any effect in the preparation. 



Chemical Analysis. 



Each one of the samples has been subjected to a complete quali- 

 tative analysis to determine the mineral ingredients present. In 

 many cases the amount of salt, epsom salts, glauber's salt, iron oxide, 

 etc., have been determined quantitatively. Sulphur, which is present 

 in many of the preparations, has been determined quantitatively by 

 the author's method.^^ The preparations which are sold under the 

 name of foods have been subjected to a complete feed analysis by the 

 official methods of the Association of Official Agricultural Chemists. 

 In determining the fat in the samples which contained sulphur the 

 ether dissolved a considerable amount of the sulphur. This was 

 determined quantitatively in the extract and the proper correction 

 made. 



On the following pages will be found the results of the chemical 

 and microscopical analyses of the samples examined. 



"J. Ind. and Eng. Chem., 3, 1, 1911. 



