294 A CENTURY OF SCIENCE 



It may be mentioned that for a number of years the 

 decision in regard to the atomic weights to be accepted 

 has been in the hands of an International Committee of 

 which our fellow countryman F. W. Clarke has been 

 chairman. In connection with this position and pre- 

 viously, Clarke has done valuable service in re-calculat- 

 ing and summarizing atomic weight determinations. 



Analytical Chemistry. 



Analysis is of such fundamental importance in nearly 

 every other branch of chemical investigation that its 

 development has been of the utmost importance in con- 

 nection with the advancement of the science. It attained, 

 therefore, a comparatively early development, and one 

 hundred years ago it was in a flourishing condition, par- 

 ticularly as far as inorganic qualitative and gravimetric 

 analysis were concerned. There is no doubt that Ber- 

 zelius, whose atomic weight determinations have already 

 been mentioned, surpassed all other analysts of that time 

 in the amount, variety, and accuracy of his gravimetric 

 work. He lived through three decades of our period, 

 until 1848. 



During the past century there has been constant prog- 

 ress in inorganic analysis, due to improved methods, 

 better apparatus and accumulated experience. An 

 excellent work on this subject was published by H. Rose, 

 a pupil of Berzelius, and the methods of the latter, with 

 many improvements and additions by the author and 

 others, were thus made accessible. Fresenius, who was 

 born in 1818, did much service in establishing a labora- 

 tory in which the teaching of analytical chemistry was 

 made a specialty, in writing text-books on the subject 

 and in establishing in 1862 the ' l Zeitschrif t fiir analy- 

 tische Chemie," which has continued up to the present 

 time. 



Besides Berzelius, who was the first to show that min- 

 erals were definite chemical compounds, there have been 

 many prominent mineral analysts in Europe, among 

 whom Rammelsberg and Bunsen may be mentioned, but 

 there came a time towards the end of the nineteenth cen- 

 tury when the attention of chemists, particularly in Ger- 

 many, was so much absorbed by organic chemistry that 



