28 MEDIUM BETWEEN MIND AND MIND. 



holding communications between mind and mind 

 all over the earth ; and is naturally employed in 

 transmitting the twinkling telegraphic communi- 

 cations which pass between the distant stars and 

 the earth. 



HEAT AND LIGHT TRANSMITTED BY MECHANICAL 

 IMPULSES IMPARTED TO THE ELECTRIC ETHER. 



Every impulse that moves portions of matter 

 disturbs the surrounding electric medium, and is 

 transmitted to the human brain through the con- 

 ducting nerves, to produce sensations of heat and 

 light when sufficiently intense. Otto Guericke 

 ( the inventor of the air-pump ). and Volta took 

 the lead in experimentally verifying the fact, that 

 every movement of one body near another dis- 

 turbs and puts in motion the electric ether in 

 both bodies, diffusing the action in various ways ; 

 as by vibrating undulations of the electric medium 

 to reach the brain through the sensorial nerves, 

 recognized as the sensations of light and heat, 

 and by movements of light bodies, such as pith- 

 balls, flexible threads, or hairs, gold leaf, &c. 

 From the ready movement of all such light bodies 

 used as tests of electric excitation, they are descrip- 

 tively denoted ELECTROSCOPES ; from the Greek 

 words ELEKTOR, solar action, and SKOPEO, / 

 behold. 



A simple mode of verifying electric dis- 

 turbances by the movements of bodies was 



