260 BENJ. PIKE S, JR., DESCRIPTIVE CATALOGUE. 



Fig. 275. 



Insulated Stool. (Fig. 275.) This consists of a ma- 

 hogany board of well-baked wood, having stout legs, 

 cemented in sockets for the purpose, sometimes having 

 screws for separating them from the top, for convenient 

 transportation. To use ; having wiped it clean and dry, 

 let a person stand upon it, holding in his hand a chain or 

 wire communicating with the prime conductor; on setting 

 the machine in action, sparks of fire may be drawn from any 

 part of his person, he becomes indeed a part of the conduc- 

 tor, and is strongly electrified ; his hair will stand on end, 

 and if he hold in his hand a silver spoon, containing some 

 warm spirits of wine, another person may set it on fire by 

 touching it quickly with his finger. 



Price, $3.00 ; with legs in brass sockets 



to unscrew, - $4.00 and $4.50. 



Fig. 276. LegdenJar(Yig. 276) is so called from 



the circumstance of its properties having been 

 first observed at Leyden. It consists of a 

 glass jar of any convenient size, usually a 

 quart, having the outside and inside coated 

 with tin foil to within two or three inches of 

 the top, and a brass wire, the upper part of 

 which terminates in a ball of the same metal, 

 and the lower part in a fine chain, or a piece 

 of fine wire, that it may touch the inside of the 

 jar, passing through a cap of baked wood 

 which fits into the mouth of the jar. If a jar 

 thus constructed be held by the lower part 

 with the hand, and the knob be brought into 

 contact with the prime conductor while the machine is in 

 action, it will become charged ; and if a communication be 

 then formed between its outside and inside coatings, by the 

 other hand being brought to the knob, that sensation called 



