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JOURNAL OF THE PLYMOUTTI INSTITUTION. 
properly applied; and they accordingly set to work to see what 
they could make of it. It would be his object in the present 
paper to show to what extent they had succeeded. 
The only form of electrical action with which they were ac- 
quainted was that in which it was developed by the friction of 
glass cylinders, or plates, against silk surfaces coated with an 
amalgam of mercury and zinc. A powerful cylinder machine 
of this kind was on the table, and the lecturer explained its 
various parts and showed its action by drawing long and brilliant 
sparks from its conductors. 
This form of electrical development, he said, was designated by 
the terms frictional, Franklynic, and static, though there were 
other modes of exciting it by means of the voltaic battery, 
the electro-magnetic, sometimes called Faradaic, and magneto- 
electric machines ; but he should confine himself that evening to 
the Franklynic. 
This form exhibited itself in three different ways; viz., by the 
spark, the shock, and the aura. The physiological peculiarities of 
the spark were first explained, and some experimental illustrations 
were given of the mode of applying it. A patient was placed on 
an insulated stool, and sparks were drawn from all parts of his 
body by means of an interrupted director, invented by the lecturer 
for modifying the length of the sparks, and obtaining them through 
clothes which were damp, or composed of conducting materials, 
and to which he had given the name of spintherometer. 
After detailing the cases for which the spark treatment was 
suitable, he passed on to describe the Leyden jar, and the various 
modes of administering the electric shock. He deprecated the use 
of the powerful shocks which were formerly administered, and 
stated that he had obtained the best results by reducing the size of 
the jar, until it became a mere coated tube of glass, which gave 
vibratory shocks precisely analogous to those experienced with the 
galvanic coil machine. These effects had been produced by him 
before Faraday had made his discovery of electro-magnetic reaction, 
or coil machines had been dreamt of. 
He next passed on to review the physiological effects of the aura 
or electrical breeze from a point, which, he said, could not be 
obtained from any of the ordinary electrical apparatus now in use. 
He considered it a most important agent in cases of sub-acute 
inflammation, weak eyes, neuralgic affections, or obstinate ulcers. 
