562 THE INTELLECTUAL RISE IN ELECTRICITY. 



fire kindled by the electrical bottle; when the healths of all 

 the famous electricians in England, Holland, France and 

 Germany are to be drank in electrified bumpers, under the 

 discharge of guns from the electrical battery." 



He had then no prescience of the great discovery which 

 he was so soon to make. It may be said that the fulness 

 of time was at hand, the environing conditions were all 

 favorable, and that if the identity of the lightning and the 

 electrical spark had not been shown by Franklin, others, 



in America Part I., 2nd ed. London, 1754. This picture became the 

 frontispiece in the later editions of the work. Figs. I, II, III, IV, and 

 V, are described in Franklin's letter to Collinson, dated July 28, 1747; 

 Fig. VI in letter IV to Collinson, and Figs. VII, VIII, IX and X, in the 

 "Opinions and Conjectures" sent Collinson in 1750. Fig. I represents 

 a Leyden bottle (r) which whenever touched by the finger attracts the 

 thread (b) suspended from the wire (a). Fig. II shows a suspended cork 

 (c) vibrating between the wires (?) (e), one of which enters the bottle 

 and the other is connected to a ring of lead upon which the bottle stands. 

 In Fig. Ill, the bottle rests on wax and is discharged by electrically con- 

 necting the interior and exterior by means of the wire (h] held in a 

 sealing wax handle (g). Fig. IV represents a bottle surrounded by a 

 ring of lead (i) connected by a conductor with the knob () on the in- 

 serted wire such a bottle says Franklin, ''cannot be electrified; the 

 equilibrium is never destroyed." In Fig. V, the jar rests on a book 

 having a gilded design on its cover; a wire (m) touches the gilding and 

 may be brought into contact with the knob of the bottle. "Instantly,'' 

 says Franklin, '' there is a strong spark and stroke and the whole line of 

 gold which completes the communication between the top and bottom 

 of the bottle will appear a vivid flame, like the sharpest lightning." 



Fig. VI is intended to show that particles at the surface of water are 

 less strongly held by cohesion than others in the body of the fluid, and 

 hence when the water is electrified are more easily repelled and thrown 

 off. Fig. VII illustrates Franklin's description of the partition of a 

 charge or "electrical atmosphere" from a Leyden jar to two suspended 

 "apples or two balls of wood" and between the objects themselves. 

 Fig. VIII is in illustration of Franklin's supposition that "electrified 

 bodies discharge their atmospheres upon electrified bodies, more easily 

 and at a greater distance from their angles and points than from their 

 smooth sides." Fig. IX is the first representation of the lightning rod. 

 Fig. X represents Franklin's " electrical fish " a piece of Dutch metal, 

 cut in the shape shown, which flies to the prime conductor of the electric 

 machine and keeps "a continued shaking of its tail like a fish so that it 

 seems animated." 



