875 



and important views — views which furnish at once the foundation 

 and the touchstone of all accurate chemical analysis. From this 

 period he was for several years actively engaged in perfecting and 

 applying the theoiy, and in determining the chemical equivalents or 

 combining proportionals of the elementary substances. The progress 

 of this long and laborious inquiry, which has furnished the most 

 valuable series of constants chemistry possesses, obliged him to exa- 

 mine almost all the elementary bodies and the principal inorganic 

 compounds then known, and which, besides enabling him to add 

 greatly to the extent and accuracy of our knowledge of these sub- 

 stances, was also the occasion of the discovery of a multitude of new 

 combinations. His researches revealed to us the existence of three 

 elementary bodies before unknown, viz. of selenium, the remarkable 

 analogue of sulphur ; of thorinum and of corium, the metallic bases 

 of two bodies of earthy character. To him also we owe our know- 

 ledge of the properties of zirconium and of silicium ; he it -was who 

 established the acid character of silica, a discovery which he subse- 

 quently applied with such happy results to the systematic classifica- 

 tion of minerals. Among compound bodies which he investigated, 

 his careful examination of the fluorides, and of the compounds of the 

 sulphurets with each other, is perhaps the most important. 



Having thus determined the chemical equii-alents of the elements, 

 Berzelius proceeded to apply his results to the science of mineralogy. 

 His well-kno-^Ti treatise on the use of the blowpipe, an indispensable 

 manual for every one who desires to derive the full advantage from 

 the employment of this useful instrument, must be considered as one 

 of his most important contributions to the literature of mineralogy 

 and of chemistry. But it is the systematic application of the doc- 

 trine of definite proportions to the analysis of mineral bodies in ge- 

 neral, which will be regarded as one of the most remarkable and 

 successful of his labours as a philosopher. So highly did the Royal 

 Society estimate this -establishment of mineralogical classification 

 upon the basis of chemistry, that they marked their sense of it with 

 the highest honour in their power to bestow, by awarding to him 

 the Copley Medal for the year 1836. The Philosophical Transac- 

 tions contain one paper by Berzelius, published in conjunction with 

 his friend Dr. Marcet, in the year 1813 ; it is entitled * Experiments 

 on the Alcohol of Sulphur, or Sulphuret of Carbon.' 



A man of such universal acquirements and acknowledged accuracy 

 w'as well-qualified to act as the historian and the censor of his sci- 

 ence, and for twenty-five years he faithfully performed these im- 

 portant ofiices. 



Careful, patient and indefatigable, he was a true personification 

 of the inductive philosopher. No labour was too great, no subject 

 too repulsive, no precaution too minute, if it promised to repay the 

 object for which the investigation was made : always relying on facts, 

 collecting, extending and multiplying them in all directions, before 

 he attempted to theorize, his theories always .naturally arose out of 

 the facts they represented, and when promulgated generally com- 

 manded ready acceptance. 



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