April 19, 1894] 



NA TURE 



589 



but the mountains which have come to him. In other words 

 the study of the chemical affinities of dead matter has revealed 

 to us the secrets of the living cell. 



The Appearance of "Vital Phenomena" in Certain 

 Chemical Solutions. 



We have been accustomed to regard the neutral solution of 

 sugar or of some neutral alkaline salt in water as an inert 

 liquid deprived of all molecular power. We know to-day 

 that such a solution must be held to possess the same kinetic 

 power as if the substance dissolved were present in the 

 gaseous state. Placed in contact with other solutions it will | 

 exercise pressure according to the laws that Avagrado and I 

 Dalton have discovered for gas. It will exercise an osmotic 

 pressure in direct proportion to its molecular weights. But 

 this is not all. We have to remember the electrolytic pheno- 

 mena of such solutions by which their kinetic power may be 

 rendered enormous. This conception of the molecular pro- 

 perties of solutions is of the highest importance both in biology 

 and pharmaco-therapeutics. It is not by accident that life is so 

 closely leagued, as it were, to water. It is not by accident 

 that living organisms contain without exception more water 

 than solid properties, that they contain much more of 

 it in proportion than any other terrestrial object of palpable 

 and visible formation. It is not by accident that 

 the youngest and most energetic organisms, those in 

 which life is, the most intense, are distinguis-hed by containing 

 the most water, while the tis ues in which life is ready to 

 expire have the least. Life has been compared to a torch. 

 From a chemical point of view life is not only a torch — 

 it may also be compared to a river. It is an ocean 

 in which the molecules of the chemical substances there con- 

 stantly dissolve, constantly develop chemical, electrical, ther- 

 mal, and mechanical energy, an energy whuse seat is the living 

 cell. 



From all of this it follows as an absolute necessity that the 

 chemical actions which constitute vital phenomena become 

 stimulated, troubled, or altogether upset from the moment that 

 we introduce into the system some new complicated substances 

 in solution, whose molecular forces are now added to those of 

 the cellular system. We are only embarrassed what example 

 to choose when we seek in organic and inorganic chemistries 

 proof of this point. I only wish to name one to you which 

 seems to me conclusive. By warming pure chlorate of potas- 

 sium we obtain pure oxygen, but the presence of the smallest 

 quantity of chloride of potassium is sufficient to change part of 

 oxygen irito ozone. In giving rise to this development of ozone 

 the chloride of potassium remains itself completely unaltered ; 

 but, what is more remarkable yet, this chloride of potassium 

 itself has, like peroxide of manganese — which acts in an iden- 

 tical manner — the property of destroying ozone. 



We find, then, here, as M. Brunck, to whom belongs the 

 honour of having discovered the reactions, has said, a most 

 remarkable phenomenon. \Ve see a chemical substance, 

 without itself appearing to undergo the least appreciable 

 molecular change, favours the formation of a new chemical 

 body, which, on the other hand, it has the power to destroy 

 the moment that it is formed. There is, in fact, in the 

 domain of organic chemistry, with no question of fermenta- 

 tion, a catalytic force, in considering which we have to make 

 for dead nature a complete pendaut of that which should we 

 scarcely consider characteristic for therapeutic actions — 

 the phenomena of excitement and paralysis, manifested 

 by the slightest possible quantities of one and the same sub- 

 stance which itself remains unaltered ! And speaking always 

 with these phenomena before our eyes and looking on the 

 cell as a colloid or membranous mass coniaining several sub- 

 stances organic and inorganic at the same time dissolved in 

 water, there is no longer any reason to be astonished that 

 slight changes in the quantity of one substance or the other, 

 or that the presence in one of a body that is absent in the 

 other, suffice perfectly to change the chemical affinity of the 

 cells, as well as to differentiate them in such a manner that each 

 of them seems to be endowed with an elective affinity peculiar 

 to itself. As for the manifestation of therapeutic and toxic 

 action by bodies considered to be insoluble,, of which Nageli in 

 a posthumous work has made so profound a study, they are 

 also capable of the simplest interpretation. The insolubility of 

 these bodies is not absolute, but only relative. If we throw, 

 for example, metallic copper into water, and wait for some 



NO. 1277, VOL. 49] 



days, we shall find that a certain proportion of the copper has 

 dissolved, i.e. one part to seventy-seven million parts of water. 

 The copper dissolves in this manner without the least inter- 

 vention of any living organism. In the same way it is not the 

 vital function of the human organism which makes arsenic, 

 cannabis indica, and lead, display active properties when intro- 

 duced in a metallic state under the skin. It is the mass of 

 water which is the agent (for the human body may be regarded 

 as a jug of water containing forty-five litres) and the tempera- 

 ture. 



The view that regards the solutions of salts as mediums in 

 which the chemical molecules are perpetually striving to 

 assert their individuality has contributed, on the other hand, 

 in the mo5t efficacious manner to elucidate the action of 

 some of the drugs that are most in use I have particularly 

 in my eye now the purgative and diuretic salts, the chlorates, 

 iodides, and bromides, whose therapeutic effects are obtained 

 upon doses that may be called massive when comparing them 

 with the infinitesimal doses of which we have just spoken. 

 Since my dear and honouted colleague of the University of 

 Amsterdam, Prof. Hugo de Vries, discovered the law of 

 i^o-tonic solutions, and since the admirable work of Prof. 

 Hofmeister of Prague and his pupils, the effects of purgative 

 and diuretic salts have been recognised to depend uniquely 

 upon their pure chemico-physical properties. On the other 

 hand, we owe to the zeal and perseverance of Prof. Hof- 

 meister of Prague again a series of very beautiful researches on 

 the imb'bition of salt solutions by tablets of jnire agar-agar 

 gelatine, which demonstrate to proof that all that we have 

 hitherto considered the elective affinity of the livin.^ cell can be 

 explained in the most natural manner in the world by its colloid 

 condition and chemical constitution. Add to this that the quick- 

 ness of chemical action, according to the interesting chemical 

 researches of Vladinarsky, is in no way impaired by the colloid 

 state of the medium in which the substances are placed, and you 

 will easily arrive at a conception of the immense progress that 

 pharmaco-therapeutics has made by the agency o( physical 

 chemistry. Among the salts that I have named, the iodides 

 and bromides are also to be found. Their therapeutic eftects are, 

 I need not say, altogether specific. What is more natural than 

 the belief that we ought to attribute the results to the iodine and 

 bromine themselves ; and we all know that some long time ago, 

 my colleague at the University of Bonn, Prof. Binz, has been 

 able to demonstrate that it is the living cell which frees the 

 iodine and bromine from solution. The fact is not, however, 

 proved to universal satisfaction. 



I should never finish my task if I tried to place before you 

 all the points of the new view on the action of drugs, poisonous 

 and otherwise, whose pharmaco-therapeutics are traceable to 

 the theories of modern chemistry. Let us glance only at the 

 catalytic fermentative action which takes place everywhere in 

 live protoplasm, and which without doubt plan a preponderat- 

 ing role ill the therapeutic effects of drugs. These can no 

 longer be considered the appanage of the living cell. They also 

 take place in dead matter. 



Chemistry in Relation to Materia Medica. 



If I now stop theorising it is not from fear lest anyone in this 

 Areopagus of science should say : To what practical good does 

 all this tend? Evidently it is not to-day or to-morrow that the 

 art of medicine will profit by chemistry. But all these new 

 ideas have rendered necessary new methods of experimentation, 

 and new methods of investigation ; and a new track is now 

 being traced by human geniu?, along which there is much to 

 discover ; and from the moment that the new physical methods 

 shall have been applied to the study of drugs (all honour to 

 M. Dreser, who has here taken the initiative in his investigation 

 into diuresis) medical art will profit and will find in chemistry 

 a sure and trusty guide in its eftorts to serve humanity. 



In speaking of chemistry in its relation lo materia medica I 

 do not employ the words materia medica in the sense in which 

 Di^corides used them. I employ them in their strictest and 

 primitive sense to mean the collection of drugs Lnd medicaments 

 in use in our days — our thesatirics 7iiedicainiiiu))i. Materia 

 medica recruits from botany, zoology, and above all from 

 chemistry; but its immense progress of late is due to chemistry. 

 The active principle of almost all our drugs are now known to 

 us. They have been isolated, prepared, and elaborated ; the 

 chemical constitution of their active principles is no longer a 

 secret. We know that sugar and glucosides, and aromatic oils 



