334 HISTORY OF SCIENCE. 



of science in particular. To the subject of atmospheric electricity the 

 attention of everybody was drawn in 1753 by the tragical death of 

 Professor Richman at St. Petersburg. RICHMAN (1711 1753), who 

 was a native of Sweden, had been appointed to the professorship of 

 experimental physics in the Imperial Academy of Sciences at St. 

 Petersburg. He was engaged upon a work on electricity, and was 

 very desirous of obtaining some data as to the intensity of the electri- 

 city of the air during thunder-storms. He had an iron rod fixed on 

 the roof of his house, and this rod was connected by a chain with some 

 apparatus which he had arranged to indicate the degree of electric 

 .action. On the day of his death, Richman had attended an ordinary 

 meeting of the Academy, and hearing the rumbling of distant thunder, 

 he hastened home in order to make observations with his electrometer. 

 He took with him an engraver named Sokolow, who had undertaken 

 to prepare the figures for the projected work, in order that the artist, 

 seeing the actual working of the electrometer, might the better repre- 

 sent the apparatus in his plates. Richman was describing his appa- 

 ratus, when a terrific clap of thunder alarmed the whole city, and from 

 the rod a ball of fire leapt to the head of the unfortunate professor, 

 who was standing at the distance of about a foot. He instantly fell 

 backwards, dead. Sokolow was stupefied for a few minutes, but was 

 not otherwise injured. 



When the great body of facts connected with electricity had been 

 'comprised under some comparatively simple general theory or prin- 

 ciple, such as those suggested by Du Fay, Franklin, Cavendish, and 

 others, little progress could be made in the science as such until its 

 chief phenomena could be under the control of mathematical laws by 

 means of exact measurement. The person who did this was COULOMB 

 (1736 1806), a French military engineer, who, after having at a very 

 early age shown extraordinary capacity for the mathematical sciences, 

 engaged in several original scientific investigations involving elaborate 

 measurements and calculations. He was a member of the commission 

 for the determination of those new weights and measures decreed by 

 the Revolutionary Government, which gave the metric system to France 

 .and to science. Coulomb himself has, by his invention of the torsion 

 balance, furnished the experimental investigator with one of the most 

 delicate and accurate instruments of measurement that can be placed 

 in his hands. 



The phenomena to be measured were the forces which displayed 

 themselves in the attractions and repulsions, that are among the 

 most obvious effects of electricity. The questions to be answered 

 would relate to the amounts of those forces under given circumstances, 

 and to the laws of their variation by distance. The way in which 

 Coulomb solved the problem presents one of the most elegant ex- 

 amples of such determinations to be met with in physical science. 

 The research was a difficult one, because the forces to be measured 



