346 sLECTRfcrrr, 



and furnished with a strong cylindrical foot, which 

 is fastened in the middle of the bottom board A. 



At7nospheric Electricity. 



The resemblance between an electric spark and 

 lightning is obvious, but the proof of their identity 

 was reserved for Dr. Franklin. He first observed 

 the power of points in drawing off the electricity 

 from bodies at great distances; and thence inferred, 

 that a pointed metallic bar, if raised to a con- 

 siderable height in the air, would become elec- 

 trical by communication from the clouds during a 

 thunder-storm. 



After having published his hypothesis con- 

 cerning the identity of electricity with the matter 

 of lightning, he was waiting for the erection of a 

 spire in Philadelphia, to make experiments on the 

 subject, when it occurred to him, that by means of 

 a common kite, he would have a readier and better 

 access to the regions of thunder, than by any 

 spire whatever. He therefore prepared a kite for 

 this purpose, and took it into the fields, attended 

 by his son. The kite being raised, the end of the 

 cord was tied to a small key. One very promising 

 cloud had passed over it without any effect; when, 

 at length, just as he was beginning to despair, he 

 observed some loose threads of the hempen string 

 to stand erect, and to avoid one another, just as if 

 they had been suspended on a common conductor. 

 Struck with this appearance, he immediately pre- 

 sented his knuckle to the key; and let the reader 

 judge of the exquisite pleasure he felt at the mo- 

 ment the discovery was complete. He perceived 



