150 THE MICROSCOPE. [July, 



the markings of the cell-wall. These markings can be well made 

 out only upon empty cells ; best of all are those found empty in 

 the gatherings, and some empty semi-cells may usually be had by 

 careful search among the sediment in which the living cells are 

 found. When they are not found patient waiting and occasional 

 examination are the remedy. 



Use of the Microscope in Pharmacy. 



By H. M. WHELPLEY, M. D., 



ST. LOUIS, MO. 



[From a paper read at the A. S. M., 1891.] 



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

 vegetable histology is of 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 histolog}^, 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 different 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 histologv ; 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 



