A HUNDRED YEARS OF CHEMISTRY. 67 



the manufacture of diamonds by Moissan, the synthesis of sugars 

 by Fischer, the discovery of soluble forms of silver by Carey Lea — 

 all these achievements and many more must be passed over. Some- 

 thing, however, needs to be said upon the utilitarian aspects of 

 chemistry, and concerning its influence upon other sciences. Por- 

 tions of this field have been touched in the preceding pages; the 

 interdependence of chemistry and physics is already evident; other 

 subjects now demand our attention. 



Medicine and physiology are both debtors to chemistry for 

 much of their advancement, and in more than one way. From the 

 chemist medicine has received a host of new remedies, some new 

 processes, and advanced methods for the diagnosis of disease. The 

 staining of tissues for identification under the microscope is effected 

 by chemical agents, the analysis of urine helps to identify disorders 

 of the kidneys; nitrous oxide, chloroform, ether, and cocaine almost 

 abolish pain. The disinfection of the sick-room and the antiseptic 

 methods which go far toward the creation of modern surgery all 

 depend upon chemical products whose long list increases year by 

 year. Crude drugs are now replaced by active principles discov- 

 ered in the laboratory — morphine, quinine, and the like — and in- 

 stead of the bulky, nauseous draughts of olden time, the invalid is 

 given tasteless capsules of gelatin or compressed tablets of uniform 

 strength and more accurately graded power. A great part of 

 physiology consists of the study of chemical processes, the transfor- 

 mation of compounds within the living organism, and practically 

 all this advance is the creation of the nineteenth century. Mod- 

 ern bacteriology, at least in its practical applications, began with 

 a chemical discussion between Liebig and Pasteur as to the nature 

 of fermentation: step by step the field of exploration has enlarged; 

 as the result of the investigations we have preventive medicine, 

 more perfect sanitation, and antiseptic surgery. The ptomaines 

 which cause disease and the antitoxins which prevent it are alike 

 chemical in their nature, and were discovered by chemical methods. 

 Physiology without chemistry could not exist; even the phenomena 

 of respiration were meaningless before the discovery of oxygen. 

 The human body is a chemical laboratory, and without the aid of 

 the chemist its mysteries can not be unraveled. 



To agriculture also chemistry is a potent ally, whose value can 

 hardly be overrated. It has created fertilizers and insecticides for 

 the use of the farmer and taught their intelligent use, and in the 

 many experiment stations of the world it is daily discovering facts 

 or principles which are practically applicable to agriculture. The 

 beet-sugar industry was developed by chemical researches and chem- 

 ical methods; the arts of the dairy have been chemically improved ; 



