1876.] 
The Newly -Discovered Force . 
185 
of the tongue was produced when he applied the tip to the 
conductor, and his head did really move up and down as 
though the muscles were affedted, but upon my breaking the 
connection unknown to him his tongue kept moving as 
before, synchronously with the respiration. It was a case 
of mind adting on body ; he expedted some effedt, and un- 
consciously produced it himself. Mr. Edison and two of his 
collaborateurs were taken sick in various ways one night, and 
it was supposed that the illnesses were caused by the force, 
but in this also they were probably mistaken ; mind adting 
on body or coincidences may account for their symptoms. 
It is certain that I have experimented many hours by day 
and by night with this force, and a considerable portion of 
the time it was passing through me or into me, and I was 
not unfavourably affedted, nor were any of those employed in 
the establishment, including Mr. Edison and the others who 
fancied their illness was caused by it. What effedt the 
force evolved from a much more powerful apparatus, and 
passed through or into the body for a long time, may have, 
primarily or secondarily, I cannot say. Some who tested 
the matter thought that a very slight tingling sensation was 
experienced on the tongue, but closer examination did not 
confirm this. 
3. The force, when generated in sufficient amount, causes 
the galvanoscopic frog to contradt. It is well known that 
the irritability of frogs varies with the season of the year, 
and also with other conditions ; hence the galvanoscopic 
frog cannot be an absolute standard or measure for eledtrici- 
city. For this reason, in all these experiments, the irrita- 
bility of the frog was tested by a galvanic current passing 
through definite resistances. We tested the frog used in 
these experiments, and found it so sensitive that one eledtro- 
poion cell, placed in a circuit having a resistance of 
400,000 ohms, or nearly 35,000 miles of telegraph wire, 
caused contradtion, and yet it did not contradt when this 
force was passed through it. That the force in these expe- 
riments passed through the frog (which was insulated) was 
proved by the spark that appeared at the distal end. In this 
experiment, the result of which was most remarkable and 
unexpedted, all conceivable elements of error seemed to be 
excluded. Subsequently — with a different apparatus, a 
Ruhmkorff’s coil — a contradtion of the muscles of the frog 
was obtained. The experiment was made at the establish- 
ment of Mr. Chester, and repeated in Newark. 
In a subsequent series of experiments, made with Mr. 
Edison, contradtion s were obtained in the frog’s leg, although 
