46 BENJ. PIKE'S, JR., DESCRIPTIVE CATALOGUE. 



struments, that his machines have been purchased, unso- 

 licited, and used by all the hospitals, infirmaries, and medical 

 institutions in the city and vicinity, by nearly all our physi- 

 cians, and over one thousand of our best citizens, as well as 

 by numerous distinguished persons in various parts of this 

 country and foreign lands. Abundant references of its 

 efficacy can be given. Many of the cures have been pro- 

 nounced astonishing. 



Description and Directions. The machine represented in 

 the previous page consists of a double coil or helix of coarse 

 copper wire, insulated, over which is wound about 1000 feet 

 of very fine insulated copper wire, in the interior of which 

 can be placed a number of soft iron wires, from one to fifty, or 

 more, and which, when the machine is in operation, become 

 powerful magnets, and regulate the strength of the power 

 according to the number used. At one end of the machine 

 is an electro-magnet, to which is attached a revolving arm- 

 ature, to distribute the power of the battery alternately, by 

 means of a silver break-piece and a silver spring, and to the 

 supports of which are soldered the wires of the two inner 

 coils, and through which the power flows by means of the 

 two brass cups (for the wires of the battery) at the side of 

 the machine. The fine wires are connected with two cups 

 at the end of the machine, and in which are secured wires 

 communicating with handles, buttons, or balls, for receiving 

 the effect. The cylindrical battery consists of a double 

 cylinder of copper, with a bottom of the same metal, and a 

 movable cylinder of zinc, with three branches to support it 

 between the cylinders of copper. The branches are covered 

 with wood, to insulate it from the copper. There are cups 

 with binding screws on each, to receive the wires from the 

 machine. The liquid employed is the sulphate of copper 

 (blue vitriol) dissolved in boiling hot water, about two 

 ounces to the quart of water, but left to cool before using. 

 The liquid requires to be renewed when the acid is entirely 

 taken up by the zinc, which will depend on thetime that the 

 zinc is left in the liquid. With care, it may be made to last 

 for 100 or more applications. The zinc cylinder should be 

 left in the solution only while the application is made, as it 

 soon becomes coated with a deposit, which should be scraped 

 off with an old knife, as a clean surface of zinc is requisite to 

 the perfect operation of the machine ; the solution may remain 

 in the copper any length of time, as it does not act on it. 



