1892.] MICROSCOPICAL JOURNAL. 89 



Use of the Microscope in Pharmacy. 



T^Y 11. M. WIIELPLEY, M. D.. 



ST. LOUIS, MO. 



[From a paper read at the A. S. M., iSgi] 

 [ Continued from fnge jo.] 



2. Use of the Compound Microscope. — a. The study of 

 vegetable histology is ot" much importance to the educated phar- 

 macist, as animal histology is to the qualified physician. While 

 work in vegetable histology does not require the use of an instru- 

 ment with as high powers or present as many difficulties as are 

 found in animal histology, still the microscope is just as essential 

 in this line of investigation as in the one followed by physicians. 

 The different vegetable tissues are as readily recognized as bone 

 and muscle. A pharmacist can as easily distinguish a section of 

 wood from a section of bark as an animal histologist can tell a 

 section of bone from a section of epidermis. The arrangement 

 of the various tissues in corresponding organs of diflerent plants 

 are quite characteristic ; thus it is that one who is versed in the 

 work can distinguish a transverse section of dandelion root from 

 a similar section of chickory root. 



This is simply one example of how the microscope will enable 

 the educated pharmacist to identify a genuine drug or detect an 

 adulteration. 



b. The United States Pharmacopoeia, the dispensatories, which 

 are commentaries upon the Pharmacopoeia, and all works on 

 materia medica for pharmacists, recognize the importance of 

 studying the microscopical appearance of transverse sections of 

 vegetable drugs. While the Pharmacopoeia is not an illustrated 

 work, it gives quite explicit descriptions of the appearance of drugs 

 as seen under the microscope. In the commentaries on the Phar- 

 macopoeia and the works on materia medica, we find illustrations 

 of the drugs as seen under the microscope. The study enables 

 the pharmacist to identify drugs, tell the quality, detect substi- 

 tutions, adulterations, sophistications, and admixtures. 



c. The study of the microscopical appearance of powdered 

 drugs has not been carried to that degree of perfection which has 

 been reached in vegetable histology ; however, the field is an 

 inviting one, and it is here that the pharmaceutical microscopists 

 of the future will be able to do the most valuable work. Some 

 idea of what can be done is shown by the work that the Depart- 

 ment of Agrriculture of the Government is doing in the examina- 

 tion of spices. .See " Bulletin No. 13" of this Department. 



Many of the histological elements of plants are such that they 

 are readily recognized, even in the mutilated condition found in 

 powders. It is often possible to identify cells from pith and other 

 characteristic tissues, like the bast in cinchona, the stone of cin- 

 namon, and the pitted ducts of red cedar. I remember an instance 

 where a sample of powdered red pepper was simply fine red cedar 



