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Proceedings of the Royal Society 
might be preserved for examination and study. I have little doubt 
that such an appeal would be attended to. Indeed, in the great 
majority of cases, a proprietor would be pleased to learn, that an 
object of scientific interest had been discovered on his estate, and 
would be glad to have it in his power to accede to any request in 
relation to it coming from a Committee of this Society. 
With regard to the mode of meeting the expenses attending the 
investigation and other proceedings suggested in this paper, it 
occurs to me that subscriptions from individuals should be chiefly 
relied on, and that the Council of this Society should only promise 
such aid as the state of the Society’s funds and their appreciation 
of the proceedings of the Committee, may suggest to them. The 
Committee will, no doubt, make a Report at least once a year of 
their proceedings, which the Council may allow to be read at a 
meeting of the Society, if its contents were sufficiently interesting. 
3. Note of a New Form of Armature and Break for a 
Magneto-Electric Machine. By R. M. Ferguson, Ph.D. 
The magneto-electric machine, which I am about to describe, 
approximates in its general arrangements to Ladd’s hand-machine. 
In it Mr Ladd makes use of a compound Siemens’ armature, con- 
sisting of two separate armatures placed in length, and revolving 
round the same axis, with their coils at right angles to each other. 
The armature revolves between the poles of an electro-magnet, of 
the description introduced by Mr Wilde. The electro-magnet, in 
the present instance, is made of a rectangular piece of boiler-plate, 
three-quarters of an inch in thickness, bent so as to form three sides 
at right angles to each other, as shown (in section) in fig. 1 . The up- 
right sides (P P' P) are nearly 9 inches high and 11 inches in length, 
and the top of the same length is 6 inches broad. Pieces of cast- 
iron (N and S) are put in the open end to form the poles of the mag- 
net. About 300 yards of a double No. 14 wire, wrapped round the 
upright sides, make the coil (COCO) of the electro-magnet. One 
of the armatures in Ladd’s machine furnishes a current to the coil 
of the electro-magnet ; the other gives out an external current. 
To distinguish the two, the counterparts of which occur in the 
arrangement I bring before you, I shall call the first the inter- 
