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ELECTRICITY. 



1 he term electricity is derived from electron, the 

 Greek word signifying amber. The ancients had 

 observed, that when a piece of amber was rubbed, 

 it acquired the property of attracting straws and 

 other light substances. 



Dr. Gilbert, in 1600, discovered that this pro- 

 perty was also possessed by many other bodies, 

 particularly sealing-wax, sulphur, and glass. Boyle 

 added to the list of such substances. Otto Gue- 

 ricke, the inventor of the air-pump, first mounted 

 a globe of sulphur on an axis, and by whirling it 

 round, excited this power more strongly than had 

 formerly been done, and gave rise to the first elec- 

 trical machines. Mr. Hawksbee, in 1709, was the 

 first person who made an electrical machine with a 

 glass globe ; since which time many philosophers 

 have added to the discoveries in electricity, parti- 

 cularly Dr. Franklin, Dr. Priestley, &c. 



To observe the phenomena of electricity in a 

 simple and easy manner, rub a large stick of seal- 

 ing-wax with a piece of dry flannel, or a glass rod 

 or tube with a piece of dry silk ; the sealing-wax 

 and glass will attract light substances, and also 

 give out a cracking noise ; and in the dark they 

 will exhibit distinct sparks of light. These sparks 



