900 



SCIENCE 



[N. S. Vol. XXXII. No. 834 



gressive of our physicians are calling for 

 a thorough revision along lines suggested 

 by the advances of modern chemistry, with 

 the elimination of much of the old matter. 

 On the other hand, certain things should 

 be added from the newer remedies and the 

 work of the council should give an insight 

 into the value of some of these. A study 

 of our work will show that by far the 

 larger part of it is devoted to an examina- 

 tion of things which have, or claim to have, 

 a fairly definite chemical composition, and 

 this illustrates an extremely important 

 point, viz., the gradual passing of an old 

 system. The pharmacopoeias of earlier 

 times contained the descriptions of a large 

 number of vegetable drugs and their 

 aqueous or alcoholic extracts, and very 

 naturally constancy or uniformity in com- 

 position was hard to secure. Extracts 

 were made by percolating or otherwise 

 treating a certain weight of the criide drug 

 with a certain weight of the solvent, but 

 there was no evidence to show that a tinc- 

 ture of aconite, for example, made from one 

 lot of the root would contain the same 

 amount of the active principle as a tinc- 

 ture made from the same weight of 

 another and different lot of the drug. Be- 

 fore the day of chemical assays the same 

 uncertainty obtained for all galenical prep- 

 arations, and even yet is not entirely 

 avoided. It must be remembered that 

 crude drugs differ as do gold mines ; some 

 are rich and some are poor in the thing 

 desired. 



The tendency in recent years has been to 

 replace the uncertain root or leaf or bark 

 by a definite weight of the active principle 

 present, the tinctures of cinchona, for ex- 

 ample, by the proper weight of the alka- 

 loids, and nux vomica by the pure 

 strychnine. The preparation of new 

 remedies becomes therefore largely a mat- 

 ter of chemistry, and in the end the chem- 



ist will be called upon to answer as to the 

 probable value. I use the term "chemist" 

 here in the broader sense, including the 

 specially trained pharmacologist, and 

 wish simply to emphasize my belief that in 

 the pharmacopoeias of the future the cri- 

 terion of chemical purity must be much 

 more rigidly enforced than in the past. 

 The developments of organic chemistry 

 have made this possible. 



It is also probable that in the pharma- 

 cology of the future the study of the re- 

 lation between intimate chemical structure 

 and physiological action will play an in- 

 creasingly important part. Pharmacology 

 is indeed concerned largely with just such 

 studies, and the prediction of action from 

 the constitution is a not impossible ad- 

 vance. There is already the accumidation 

 of a great deal of evidence bearing on the 

 effect of introducing various substituting 

 groups for hydrogen of aromatic radicals. 

 Consider, for example, the different toxi- 

 cities of the several hydroxybenzenes, the 

 difference between benzoic acid and sali- 

 cylic acid, the difference between acetani- 

 lide and phenacetin due to the presence 

 of an ester group in the molecule of the 

 latter. The possibilities in this direction 

 are shown most emphatically in the re- 

 markable series of artificial cocaine deriva- 

 tives. Hundreds of these have been made, 

 and among them we have bodies of consid- 

 erable usefulness, the eucaines and sto- 

 vaine, for example, along with many of no 

 apparent value. With the great number 

 known it should be now possible to dis- 

 cover by experiment the reasons for the 

 activity in some cases, or the inertness in 

 others. The question of therapeutic value 

 should be worked out for all such sub- 

 stances and as knowledge advances it is 

 hoped that the measure of value may be 

 based on chemical properties and struc- 

 ture. 



