ELECTRICAL AND THE SIPHON RECORDER. 363 
poles of a powerful electro-magnet, and the electricity coming 
from the cable is led through this coil, which thereupon expe- 
riences a force, and is deflected. The siphon, with ink con- 
tinually jetting from it in a fine rain, is connected with the 
coil so as to move when it moves from side to side across 
a narrow riband of paper which travels past the point of the 
siphon. The paper “moves with a certain velocity, and receives 
upon its surface the track of the ink-shower in a straight line 
when no message is being sent, but in an irregular, wavy line 
when the siphon is recording. 
The siphon (s) upon fig. 1 [next page] is about the thickness 
of a horse-hair, and is made of capillary tubing so fine in the 
bore that ink will not run in it owing to the influence of capillary 
attraction. In order to make it squirt upon the paper, the ink 
requires to be electrified to a higher (positive or negative) 
potential than the paper. This is effected by an arrangement 
which generates electricity of high potential, and, as its form 
in the recorder bears a strong resemblance to one of those 
drums turned by white mice* and the force necessary to rotate 
it has been reckoned in 66 mice-power,” it has been termed the 
“ mouse-mill.” 
The principle of the mouse-mill is that of statical electric 
induction — the name given to that property by which elec- 
tricity on a body is enabled to draw forth electricity of an 
opposite kind to itself upon the nearest parts of any neigh- 
bouring conductor, and to drive electricity of the same kind as 
itself into the parts remote* The mill-wheel is a noncon- 
ducting disc of ebonite, with composite carriers of brass and 
soft iron set all round its circumference. The poles of an 
electro-magnet are placed so as to attract the iron parts of the 
u carriers,” and there are special arrangements for effecting this 
so as to keep the wheel rotating uniformly in one direction at 
certain velocities. Part of the electricity stored upon the 
inductor a is milked off by a wire and led to the ink, which it 
electrifies strongly, and, by virtue of a repulsion among its 
own particles, the ink escapes down the siphon, and breaks in 
spray upon the paper. A rapid vibratory motion, given to the 
point of the siphon by electric attraction and repulsion between 
it and the paper, helps also* to produce the dotted character of 
the markings. 
The coil itself c is made of extremely fine copper wire, and 
is so light that one of 100 ft. in length of this wire weighs 
only about 26 grains. It is made of a rectangular form, about 
2 in. long, and J broad, being stiffened with shellac varnish. 
The sides of a central piece of soft iron i and the poles of 
the electro-magnet m m outside, are hollowed out so as partly 
to surround the convolutions of the coil and concentrate upon 
