ELECTRICAL APP1MTCT 



PIKE'S IMPROVED PLATE ELECTRICAL MACHINE. 



THIS elegant electrical machine (Fig. 266, opposite page) 

 is mounted on a large base, supported from the floor by four 

 stump feet, and on the top there are fastened by screw bolts 

 two turned columns, with a cap also fastened by screw 

 bolts ; near the centre of the columns, the axle, made of 

 polished steel, is supported, bearing the plate, which is 

 pressed at opposite sides of its circumference, by two pairs 

 of elastic rubbers, secured between the columns ; the press- 

 ure of the rubbers may be regulated at pleasure ; to one 

 end of the axle the winch and handle is fixed, by which the 

 plate is easily turned. The conductor consists of two up- 

 right brass tubes, two and a half to three inches in diameter, 

 having large brass balls at each end and in the middle, 

 also a cross tube connecting the two together at the top, 

 and having a ball in the centre. From the lower balls and 

 opposite the centre of the plate; there are brass arms extend- 

 ing half across the plate, with rows of teeth for collecting 

 the fluid from both sides of the plate. The conductor is 

 supported on bases, by four strong glass pillars, set at each 

 end in brass sockets, and secured to the base by screw bolts, 

 all of which may be taken apart for convenient transporta- 

 tion. These machines are made with plates of 24, 27, 30, 36, 

 and 44 inches in diameter, with framework in proportion 

 made of mahogany or rosewood, handsomely polished, and 

 with conductors of brass, highly finished, from four to seven 

 feet high, having balls, wires, and suitable holes for connect- 

 ing other apparatus. These machines are by far the most 

 durable and elegant in their construction of any in use ; 



