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*¢ Though my machine is tolerably well known to the public from 
its constant exhibition at the Adelaide-street Gallery since August, 
1833,’ Saxton continues, ‘‘ and my claims as its inventor have been 
acknowledged by Professors Faraday, Daniell and Wheatstone, in 
papers of theirs published in the Philosophical Transactions, yet as no 
description of it has yet been published I will thank you to insert 
the following in the ensuing number of the PAz/osophical Magazine.’’* 
Then follows an illustrated description of the Saxton machine 
of 1833. 
In this article he says: ‘* The first electromagnetic machine, 
that is, an instrument by which a continuous and rapid succession 
of sparks could be obtained from a magnet, was invented by M. 
Hypolite Pixii, of Paris, and was first made public at the meeting 
of the Academie des Sciences on September 3, 1832. .... It 
differs from mine principally in two respects: first in M. Pixii’s 
instrument the magnet itself revolves and not the armature; and 
secondly, the interruptions instead of being produced by the revo- 
lution of points, were made by bringing one of the ends of the 
wire over a cup of mercury, and depending on the jerks given to 
the instrument by its rotation for making and breaking the contact 
with the mercury.’’ With regard to the double armature in his 
machine, Saxton says that he was led to it by the following circum- 
stances: ‘‘ In November, 1833, Count di Predevalli brought from 
Paris one of M. Pixii’s machines, and it was sent to the Adelaide- 
street Gallery in order that its effects might be compared with 
those of mine. Mine was found to excel in the brilliancy of the 
spark, while M. Pixii’s machine was more effective in giving the 
shock and affecting the electrometer. M. Pixii’s machine had a 
larger keeper and a much greater extent of copper wire. Shortly 
after Mr. Newman, of Regent street, made a smaller instru- 
ment on my construction, which gave the shock more power- 
fully than my large one did; this also had a greater length of coil, 
but the effect was at that time partly attributed to the better insula- 
tion of the wire. I then convinced myself by some experiments 
that the increased shock solely depended on the length of the 
wire. ‘The cause of the difference of effect in the two cases ad- 
mitted no longer of dispute after the publication of the experi- 
ments of Dr. Henry, of Philadelphia, of Mr. Jennings and of Dr. 
Faraday ; as their investigations fully proved that the spark is best 
* Phil, Mag., III, ix, 8360, November, 1836. 
