1876.] 
The Newly -Discovered Force 
179 
President Morton, of the Stevens Institute, Hoboken, also 
generously placed at our disposal, for experiment, the mag- 
nificent apparatus of that Institution, and personally aided 
us in some of the investigations. 
Method of Obtaining the Force . 
All that is necessary to generate the force is a galvanic 
current of considerable strength, interrupted by a tele- 
grapher’s key, and passing through a small coil of fine wire. 
In order to capture the force, a piece of iron or cadmium or 
carbon may be laid across the end of the coil, or within the 
coil if it be a single coil. To this piece of metal a wire of 
iron or copper may be attached, and by this conductor the 
force may be led off to the gas-pipe or any other earth- 
connedtion, or to a stove or stove-pipe, or, indeed, to any- 
thing that adts as a condudtor. Mr. Edison is quite positive 
that cadmium gathers the force somewhat better than any 
other metal. I have not seen or made any experiments in 
the comparative condudtibility of different metals. 
A battery current of considerable strength is needed, 
5, 10, 15, or 20 Bunsen’s cells; the number varying with 
the coil of eledtro-magnet used, and with the size of the 
batteries, and with the strength of the solution. It is pro- 
bable that the force is generated even when fewer cells are 
used, but not always in sufficient quantity to give a spark, 
and hence we have no way of studying it, or of demon- 
strating its existence. The spark has been obtained when 
but four or even two cells were used. The interruptions 
may be slow or rapid. When slow interruptions are used, 
it is found that the spark of the force appears only on the 
opening of the circuit. 
The above is probably the simplest method of obtaining 
the force, and least liable to error, and is therefore better 
adapted for experiments. Instead of a single coil without 
a core, there may be double coils with cores, and across the 
ends of these a piece of iron or cadmium may be placed. 
Small spools of fine wire seem to be preferable to large 
spools of coarse wire, and magnets with large cores do not 
seem to develope the force — at least our experiments with 
very large magnets thus far have been failures. From the 
immense magnet in Stevens Institute, Hoboken, we could 
get nothing. A number of physicists, in different parts of 
the country, who have attempted to obtain the force from 
large magnets, or from magnets with large cores, have en- 
tirely failed. The very natural supposition that the larger 
