LECTURES ON ELECTRICITY. 
357 
blisbed law that two positive bodies repel each 
other, that the comet will be repelled with a 
velocity corresponding with the intensity of 
the charge in each of the two bodies, and as 
negative and positive bodies attract each other, 
it will be attracted with an equal power into 
the region of negative electricity ; but as the 
attractive power of this region is equal on all 
sides, the comet will not be attracted to any 
given point, but will follow the original curva- 
ture of its orbit first imparted upon its emission 
from the sun ; as the comet penetrates into 
the region of negative electricity, its charge will 
be gradually withdrawn or dissipated; and as 
this process proceeds, the velocity with which 
it moves must necessarily decrease, and, at a 
certain point, the attractive and repulsive 
forces must be in equilibrio, until at length 
the whole, or nearly the whole, of the charge 
is withdrawn, and the comet being now ne- 
gative, is attracted by the sun, and repelled 
by the region of negative electricity. As 
the nucleus and materiel of the comet has a 
strong affinity for the electric fluid, as it ap- 
proaches the denser part of the sun's electric 
atmosphere, it will imbibe the fluid, and, 
consequently, cannot enter into the body of 
the sun, but will be again repelled in an orbit 
less elliptical than that described in its first 
revolution. In order to form a competent 
conception of the manner in which this effect 
is produced, we must refer to the electrical 
phenomena exhibited by a stream ofelectricity 
in its passage between the two points of a 
positive and negative conductor ; here we 
perceive, that “ the velocity will carry the 
particles that have deviated from a direct 
course somewhat beyond the point to which 
they are attracted ; while the attraction to this 
latter point will tend to deflect them from the 
line of their path, and gradually turn them 
back, so that they wall arrive at the point of 
attraction by a retrograde motion.” Now as 
the deflection must necessarily correspoml with 
the size of the point of attraction, and as the sun 
is a body of immense magnitude, it follows that 
the comet will be deflected in its path in a 
curve corresponding with the circle of the sun’s 
electrical influence; and as the repulsion 
between the sun and comet is an increasing 
force at the peiiod of the latter’s perihelion ; 
and as this repulsive force is exei ted equally 
on all sides of the sun, a portion of this force 
must press laterally on the comet in its orbit, 
thereby tending to widen the ellipsis. This 
part of our theory derives a support almost 
amounting to demonstration, from the fact 
that “ when comets first make their appear- 
ance, they generally resemble a round film or 
vapour, with little or no pretensions to a tail, 
but they increase in brilliancy and the acquisi- 
tion of a tail as they draw near to the sun ; 
but it is after they have [)assed their perihelion, 
when emerging from the brilliancy of the 
solar light, in which they have been for a short 
time obscured, that they assume their greatest 
splendour the tail which, during the 
approach to the perihelion, had followed the 
comet, now precedesit generally with asmall 
degree of curvature, probably arising from the 
resistanceof the ether, which is supposed to 
pervade all space.” The increased brilliancy 
must be ascribed to the increased quantity of 
electiic fluid that the comet has imbided in 
its passage near the sun; and the tail being 
projected from the sun, is plainly to be referied 
to the repulsive force exerted between two 
bodies both positively charged, or, perhaps, 
with more strict propriety, to the inductive 
influence ofelectricity, repelling and concen- 
trating the electric fluid in the remotest part of 
the comet’s tail. Now as tliecometcannot be 
so highly charged by passing through the 
electric atmosphere as when first disengaged 
from the sun, it follows that the repulsive 
power is weaker, and that, consequently, it 
will not be projected to the same distance as in 
its first revolution. From these considerations 
we draw this conclusion, that in the course of 
“ series of revolutions, the orbit of a comet 
becomes less elliptical ; its projected distance 
from, and its approximation to, the sun 
becomes less in nearly an equal ratio,” VVe 
must further observe, that during the come- 
tary state, the materiel of the comet undergoes 
certain specific changes relative to its electiic 
functions; the tail is gradually absorbed by 
the nucleus, and when its orbit is reduced to 
the planetary form, it takes its station in the 
exterior circle of the planets, a well-matured 
and compacted body, a fit recipient and sup- 
porter ofvegetable life. 
5. VVe have laid it down as a fundamental 
law in this tlieory, that the eaith and all the 
planets of the solar system are maintained at 
ihcir respective distances from the sun, and 
each other by the relative proportions of posi- 
tive and negative electricity with which each 
is charged ; and we further assume, that the 
positive cliarge is a continually decreasing 
quantity Irom the time of a comet’s first emis- 
sion fiom the sun, until it finally falls back 
into that body a worn-out and exiiausted pla- 
net. We have no data whatevei wluc-h would 
enable us even to attempt to fix the time occu- 
pied in accomplishing these vast operations of 
nature, each specific change in bodies of such 
immense magnitude must require i>eiiods of 
vast duration ; compared with which, the 
age of human records is but as one day. We 
are assured by experiment, that the attractive 
and repulsive forces ofelectricity follow the 
same law as to its intensity, that is, the inverse 
ratio of the square of the distance. Lelthishe 
compared with the laws of Kepler, and 
we think the conclusion cannot be resist- 
ed, that the motions and distances of tlie 
planets are regulated and determined by 
this powerful and all-pervading agent. If 
we endeavour to estimate by the operations 
of sense the manner in which the planets 
aresaid to be propelled in their orbits with 
such amazing velocity, we feel a difficulty 
in perceiving tlie cause of motion — tiie effect 
is admitted, hut the cause is not discernable , 
but if we refer all motion to the agency of 
electricity, the cause and effect are joined 
before our eyes ; we refer it to an ev. r-active 
and known power, appreciable by the senses, 
pervading all known space, and whose rapid 
motion corresponds with the motion of the 
heavenly bodies ; and if we allow the assump- 
tion, that the quantity of positive electricity 
with which the earth and all the planets is 
