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SCIENCE 



[N. S. Vol. XLin. No. 1104 



truth, regardless of its possible utility ; an- 

 other strives to apply the truth to the mate- 

 rial welfare of mankind. The truth comes 

 first, however; its applications only follow. 

 The great edifice of applied science rests 

 upon foundations of pure research. The 

 work of Gilbert, of Galvani, of Volta, of 

 Faraday, preceded the electrical advances 

 of to-day. The seemingly useless discov- 

 eries of one generation have made modem 

 inventions possible. In every department 

 of science this principle holds true, and in 

 none more than in chemistry. A single 

 fact, insignificant by itself, may be the final 

 link in an important chain of evidence. 



The uses of a discovery can not be fore- 

 seen. Aniline was useless for many years 

 after its discovery, but its importance is 

 much in evidence to-day. Bromine and 

 iodine were chemical curiosities at first, but 

 they had much to do with the development 

 of photography; an art which came into 

 existence years after the two elements were 

 first made known. So-called rare metals, un- 

 important only thirty years ago, have now 

 found applications and are commercially 

 valuable. Tungsten and vanadium are used 

 in hardening steel, and tungsten also forms 

 the filaments of incandescent lights. 

 Thorium is utilized in the Welsbach mantle, 

 chromium and titanium have found new 

 uses; and the list might be iadefinitely ex- 

 tended. Discovery came first, utilization 

 was always much later. Modern bacteriol- 

 ogy grew out of a controversy between two 

 chemists, Pasteur and Liebig, who held op- 

 posing views as to the nature of fermenta- 

 tion. They fought over principles, and the 

 practical consequences of the final decision 

 could hardly have been anticipated. 



Every argument has two sides. If ap- 

 plied chemistry owes much to pure chem- 

 istry, it has given much in return. It has 

 stimulated research and suggested new 

 problems. An honest investigation in the 



field of applied science is likely to yield 

 some data of no immediate use in industry, 

 but nevertheless of real scientific interest. 

 Such data are often more than isolated 

 facts, for they may fill gaps in our knowl- 

 edge, or serve as evidence in the establish- 

 ment of some principle. The search for 

 useful derivatives of coal-tar, for example, 

 has led to the discovery of thousands of 

 compounds which, although commercially 

 unavailable, have yet helped to build up 

 the colossal structure of organic chemistry. 

 Theory has aided practise, and practise has 

 done much to strengthen theory. Neither 

 side can claim absolute supremacy. 



In all that I have said so far there is 

 nothing new, at least to men of scientific 

 training. We all know the outlines of 

 chemical history, and can agree in a gen- 

 eral way as to fundamental principles. But 

 knowing and realizing are two different 

 things. "We become so accustomed to ob- 

 jects immediately about us that we often 

 fail to realize their presence unless they 

 are constantly used. It is the same with 

 principles and ideas. The work we are 

 actually doing absorbs our thoughts, and we 

 forget or unconsciously ignore the equal, 

 perhaps greater importance of other things. 

 "We know but do not realize. The most 

 obvious truths are those which oftenest 

 need to be recalled. They are so obvious 

 that they no longer attract attention. On 

 occasions like this it is permissible to em- 

 phasize them, and truisms become respect- 

 able. 



I speak now to experts; but what of the 

 layman, the employer of labor, the con- 

 sumer of scientific results ? How far can he 

 be made to realize that his applications of 

 science rest, not upon empirical experi- 

 mentation, but upon a long line of seem- 

 ingly abstract researches, guided by theories 

 which to him appear to be visionary f 



To this question no general answer can 



