The Bell System Technical Journal 



Vol. XV October, 1936 No. 4 



Microchemical and Special Methods of Analysis 

 in Communication Research 



By BEVERLY L. CLARKE and H. W. HERMANCE 



Analysis was beginning: to take its place as an important branch of chem- 

 istry when, in 1828, Wohler synthesized urea and the Age of Synthetic 

 Organic Chemistry was born, destined to overshadow analysis for nearly 

 a century. When interest in synthesis began to diminish, in the late 1800's, 

 physical chemistry arose to intrigue the chemical mind. The analyst, thus 

 neglected, had to work with apparatus, techniques and viewpoints evolved 

 for other chemical purposes. In 1910 the Austrian Pregl found it necessary 

 to analyze a sample too small for the then available technique to handle. 

 His solution was the invention of a new kind of analysis — microanalysis, the 

 essential features of which are: reduction of apparatus size and of scale of 

 operations to a point commensurate with sample size; development of en- 

 tirely new techniques, apparatus and chemical reactions specially suited to 

 analysis; and inculcation in the mind of the analyst of the attitude that 

 analytical problems are, in greater or less degree, research problems, and are 

 to be approached as such, with a mind entirely unrestricted by chemical 

 classicism. This article discusses the applications made by the Bell 

 Telephone Laboratories of microanalytical and related special technicjues to 

 communication research and engineering. 



THE beginnings of chemistry are lost in antiquity. The basic 

 entities of the early natural philosophers, earth, air, fire and 

 water, gradually gave way to the more numerous and fundamental 

 entities, the elements. In the Middle Ages the alchemists concen- 

 trated their talents on an unsuccessful attempt to change base metals 

 into gold. Although these men were, wath several notable exceptions, 

 charlatans and fakers, they did focus attention on matter and its 

 objective properties. As early as the 5th century, B.C., Thales of 

 Miletus proposed an atomic theory; but it was John Dalton who 

 twenty-three centuries later formulated the modern Atomic Theory 

 which is the foundation-stone of chemistry. 



In the intellectual gropings of man, atoms and molecules, in due 

 course of time, became concepts that explained many phenomena. 

 During all these years there has been a search for the single entity of 

 which all matter was made. Front's hypothesis of the early 19th 

 century named hydrogen as this single elemental substance. By the 

 end of the 19th century and the beginning of the 20th the one element 



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