and Laboratory Methods. 2525 



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LABORATORY PHOTOGRAPHY. 



L. B. ELLIOTT. 

 Devoted to Methods and Apparatus for Converting an Object into an Illustration. 



The Lantern in Class Room of Pharmacognosy. 



The primary object of Pharmacognosy, as more especially adapted to the 

 needs of students of pharmacy, is to enable him to recognize drugs, to determine 

 their quality, to detect their adulteration and to distinguish the characteristic 

 elements of those to which they are closely allied. The study of the develop- 

 ment of different organs of plants and of histological changes of their growth 

 and the botanical relations of orders, genera and species, while helpful and 

 important in many ways, is not so directly applicable to his needs as the study 

 of histological elements, by the aid of the microscope. 



This microscopical study has been applied especially to powdered drugs and 

 in this work considerable progress has been made within the past few years. It 

 is now quite possible to identify most of the official drugs of the materia medica, 

 even in the powdered form, when the gross characteristics have disappeared in 

 the progress of pulverization. This has been accomplished by the faithful 

 workers who have devoted much time to the study of what may be termed the 

 inner morphology and the investigation of the air dry material as it exists in the 

 somewhat changed vegetable cell — changed in the process of dessication. 



As evidence of this work there have been most excellent papers and mono- 

 graphs upon powdered drugs published, and during the past few years, also,, 

 there have been issued text-books and volumes upon the subject, such as : " Pow- 

 dered Vegetable Drugs," by Albert Schneider, M. D., Ph. D.; "A Course in 

 Botany and Pharmacognosy," by Henry Kraemer, Ph. D., Ph. B.; " Microscopical 

 Examinations of Foods and Drugs," by Henry George Greenish. Last year there 

 was completed the " Anatomischer Atlas, Der Pharakognosie und Nahrungsmit- 

 telkunde von Dr. A. Tschirch und Dr. O. Oesterle." 



Formerly it was considered sufficient for identification of vegetable drugs to 

 describe gross characteristics only, such as color, odor, taste, and such other 

 characters as might be brought out by the simple microscope, magnifying, say 

 ten to fifteen diameters, but this method has become inadequate because of the 

 new factor in drug supplies — the drug miller. He supplies these in powdered 

 form, and the process of pulverization the druggist is glad enough to transfer to 

 those who have laboratories especially provided for that purpose. But it is easy 

 to see that adulteration is made easier and its detection more difficult, hence it 

 is necessary to teach every student in pharmacy methods of microscopical analy- 

 sis of drug powders. 



In order to detect adulteration in a vegetable powder it is necessary to 

 become thoroughly acquainted with the structure of the drug of which the pow- 

 der is made and to have a knowledge of the different elements contained in the 



