Electroluminescence 285 



possible to draw such powerful sparks from human beings that they 

 " nearly fell down with giddiness." A letter in the Phil. Trans, for 

 1745 by Georg Mathias Bose (1710-1761) , professor of experimental 

 philosophy at the Academy of Wittemberg and the man who added 

 the metal prime conductor to the electrical machine around 1733, 

 alleged " the Motions of the Heart are very sensibly increased " 

 when a man is electrified in a chair suspended by silk ropes. " In 

 the dark a continual Radiance or Corona of light appears incircling 

 his Head, in the manner Saints are painted." This was spoken of as 

 beatification. If a vein were opened while electrified the blood that 

 flowed out appears " lucid like phosphorus, and runs out faster than 

 when the man is not electrify 'd." It was also observed that water 

 spouting from an artificial fountain " scatters itself in little lumi- 

 nous drops; and a larger quantity of water is thrown out in any 

 given time, than when the fountain is not made electric." ^° 



According to Priestley (1769: 149) , Bose's experiment on beatifi- 

 cation set the electricians of all Europe to work but none were able 

 to repeat the experiment and observe the luminous halo, and Bose 

 later ^^ admitted that he had used a suit of armor rather than a 

 man, and that when the electrification was very vigorous the edges 

 of the helmet shot forth rays such as are painted on the heads of 

 saints. Many other marvellous virtues of electricity, the passing of 

 odors through glass by J. H. Winkler and effects of a medical nature 

 were announced at this time but later shown by W. Watson to be 

 without foundation.^2 



Bose also ignited ether and other inflammable vapors, and ob- 

 served the discharge in exhausted glass vessels, a light which " flowed 

 and turned and wandered and flashed," so that he compared it with 

 the aurora borealis. He was perhaps the first " electrical wizard," 

 who delighted in theatrical display of electric effects and helped to 

 start the vast popular interest in lectures and exhibition of electrical 

 phenomena which lasted for years. 



A contemporary of Bose, Christian August Hansen (1693-1743) , a 

 professor of mathematics at the University of Leipzig, in 1743 dis- 

 tinguished three kinds of electric light, the spark, the brush, and 

 the glow. He regarded the ether of Newton and electric matter to 

 be the same because both can glow and argued that this matter 

 must be present in the blood, because electric fire can be drawn 

 from human beings. Hence the blood may be the seat of the soul. 



^"Francis Arago collected many instances of luminous rain drops, mentioned in 

 T. L. Phipson, Phosphorescence, 45-46, 1862. 



" In a letter published by W. Watson (1750) . 



"See W. Watson, Phil. Trans. 46:348-356, 1750 on Bose and 47:231-241, 1751, on 

 Winkler. 



