ELECTRICITY. 



127 



trical appearances which he would have to represent in the plates. While 

 Richmann was describing to Sokolow the nature of the apparatus, a thunder- 

 clap was heard louder and more violent than any which had been remembered 

 at St. Petersburg. Richmann stooped toward the electrometer of the appara- 

 tus to observe the force of the electricity, and " as he stood in that, posture, a 

 great white and bluish fire appeared between the rod of the electrometer and 

 his head. At the same time a sort of steam or vapor arose, which entirely be- 

 numbed the engraver, and made him sink on the ground." Several parts of 

 the apparatus were broken in pieces and scattered about. The doors of the 

 room were torn from their hinges, and the house shaken in every part. The 

 wife of the professor, alarmed by the shock, ran to the room, and found her 

 husband sitting on a chest, which happened to be behind him when he was 

 struck, and leaning against the wall. He appeared to have been instantly 

 struck dead.* 



During 1752 and the succeeding years the subject of atmospheric electricity 

 engaged the attention of persons devoted to physical science in different parts 

 of Europe. The climate of England being less favorable to such researches 

 than more southern latitudes, fewer opportunities of observation were offered ; 

 nevertheless, Canton, Wilson, and Bevis, soon repeated and verified the Phila- 

 delphia experiments. Canton showed that the clouds were electrified, some- 

 times negatively and sometimes positively, and carried such observations fur- 

 ther than Franklin. A 



But the most acute and indefatigable follower of Franklin at this time, in at- 

 mospheric electricity, was Beccaria, who, in 1753, published a treatise on 

 electricity at Turin, and a series of letters on the same subject, at Bologna, in 

 1758. He erected numerous conducting rods in different places of observa- 

 tion, and elevated kites according to Franklin's method. By raising these to 

 various heights, he observed the electricity of different atmospheric strata, and 

 he improved this mode of observation by interlacing the strings with metallic 

 wire. To keep his kites constantly insulated, and at the same time to give 

 them more or less string, he rolled the string upon a reel, which was supported 

 by pillars of glass, and his conductors were placed in metallic communication 

 with this reel. 



This profound philosopher, and acute and accurate observer, has left in the 

 history of electricity traces of his genius second only to those with which 

 Franklin and Volta impressed it. Beccaria was the first who diligently studied 

 and recorded the circumstances attending the phenomena of a thunder-storm. 

 He observes that the first appearance of a thunder-storm (which generally hap- 

 pens when there is little or no wind) is one dense cloud or more, increasing 

 rapidly in magnitude, and ascending into the higher regions of the atmosphere. 

 The lower edge is black and nearly horizontal, but the upper is finely arched 

 and well defined. Many of these clouds often seem piled one upon the other, 

 all arched in the same manner ; but they keep constantly uniting, swelling, and 

 extending their arches. When such clouds rise, the firmament is usually 

 sprinkled over with a great number of separate clouds of odd and bizarre forms, 

 which keep quite motionless. When the thunder-cloud ascends, these are 

 drawn toward it ; and as they approach they become more uniform and regular 

 in their shapes, till, coming close to the thunder-cloud, their limbs stretch mu- 

 tually toward one another, finally coalesce, and form one uniform mass. But 

 sometimes the thunder-cloud will swell and increase without the addition of 

 these smaller adscititious clouds. Some of the latter appear like white fringes 

 a', the skirls of the thunder-cloud or under the body of it, but they continually 

 grow darker and darker as they approach it. 



* Phil. Trans., vol. xlix., p. Cl. 



