P L A 
We know that the gas in which we live afts thus at defi¬ 
nite diftances, in proportion to the clofenefs of the place 
of experiment; and we mud not forget, that in the only 
fituation in which a good experiment could be made, the 
efteft of this continuous power in mere gas was very re¬ 
markable: viz. when Blanchard and Jeffreys eroded the 
Straits of Dover, they threw from their car, when at the 
elevation of two miles, an empty bottle, the fall of which 
on the water produced aJharp cuncuffion in the car, thereby 
affording proof of the continued impulfe of gas, even 
when the impulfe is made in free fpace. The afeent of 
found, and its propagation through diftances of three or 
four hundred miles near the earth, is a further proof of 
fuch capability, though the vibrations of found are not 
exaftly of the fame nature as the propulfion of impulfe. 
This important confequence follows ; “ that, as impulfes 
in a gafeous medium muff adit in cones diverging from 
the moving power, fo the force of the impulfe muff necef- 
l'arily diminifh as the fquares of the diftance ; the impulfe 
from a focus through gas being of the nature of the im¬ 
pulfe of light, heat, and all emanations.” 
Thefe are the poltulata on which I propofe to raife a 
new theory of the univerfe, without the aid of gravita¬ 
tion. And on thefe bafes it cannot be difficult fo to com¬ 
bine the laws of motion as to account for all the ordinary 
phenomena of the univerfe. In fuch coniiderations, the 
governing principle is an exaft fitnefs and harmony be¬ 
tween caufes and efteft; and thefe impofe the neceffity of 
a balance of powers. A balance of powers requires, 
however, equal momenta; and equal momenta grow out 
of equal quantities of motion, on two fides of a fulcrum, 
centre, or axis. 
In univerfal nature there is no up nor down ; there is 
no natural difpofition of bodies to fall together, or to re¬ 
cede from one another; and no phenomenon is produced 
but by analogous caufes exaftly equal to the efteft. 
Thus motion neceffarily produces motion, and the exift- 
ence of motion affords proof of the exiftence of a caufe 
in tome fuperior motion. Difturbanceis always counter¬ 
acted by the inertia of matter, and the mutual conteft be¬ 
tween the moving agent and the moved patient caufes 
both to turn round the centres of their maffes, or round 
a fulcrum, on each fide of which the quantities of motion 
are forced to feek equality. 
In the folar fyftem, the Sun is the moving power of all 
the planets. Whatever be the origin of its own motions, 
the Sun adits, in the economy of the planetary bodies of 
the folar fyftem, like the heart in the economy of the ani¬ 
mal fyftem. Its own motion may be created by fome ar¬ 
rangement within itfelf; -by a perpetual motion of di¬ 
vine contrivance; by the crofs and reciprocal aftions of 
the planets; or, according to an hypothefis of Herfchel, 
it may have a fuperior orbit among fyftems of funs ; and 
our planets and their fatellites may be its fecondaries and 
fub-fecondaries! It will, however, fatisfy the fpirit of 
philofophy, if we can trace all thofe motions, which have 
hitherto baffled enquiry, to the natural aftion of a primum 
mobile like the Sun ; and we maybe content there to ter¬ 
minate our inquiries, at lead for fome ages. Thus much 
feems certain, that the motions of the folar fyftem may 
be correftly likened to that of a pentagraph or polygraph ; 
the planets mimicking the motions of the central mafs, 
juft as the tracing points mimic thofe of the original in 
the aftion of that machine. Or perhaps the motion of 
the Sun may be compared to that of the hand while 
whirling a firing with a weight at the end; the hand 
moving through a circle of one or two inches, giving 
thereby an orbit of feveral yards to the weight at the 
end of the firing. In univerfal fpace, however, and in 
performing abfolute motion, the planets move in no re¬ 
lations like that of the weight to local and relative 
powers; and therefore have no inclination to fly off in a 
tangent. Indeed the difpofition to fly off in a tangent, 
and fall to the Sun, given to the planets by the Newto¬ 
nian philofophy, are gratuitous affumptions, which one 
Voji. XX. No. i 394 . 
NET. 597 
almoft blufhes to name, and are unfupported by any ana¬ 
logy unwarranted by the univerfal ffmplicity of the ma¬ 
chinery of nature. 
In tracing the effefts from their caufes, let 11s fuppofe 
the folar fyftem to be llationary : let the Sun, whofe mafs 
is a given number of times greater than either of the 
planets, be moved one foot; then will each of the pla¬ 
nets be moved in the fame direftion, according to a ra¬ 
tio governed by the pofitions and bulks of the whole, a 
certain number of feet, as 100,000 or 1,000,000 feet, ac¬ 
cording to circumftances. Such a circular motion of a 
preponderating central mafs, ailing on and through the 
medium of fpace upon the planetary bodies, or upon any 
aggregations of matter, would propel them into corre- 
fponding motions, with forces varying reciprocally as the 
fquares of the diftances, and direftly as the quantities of 
matter to be moved. Hence the orbicular motions of the 
planets. If the velocities were as the forces exerted, and 
the momenta were as the matter compounded of the 
fquare of the velocities, then the quantities of motion at 
each end of the line of aftion would in theory be equal. 
If the refuit of this aftion were a balance of the mo¬ 
menta in the moving bodies, as direftly exerted and dif- 
fipated in the medium of fpace, then the orbicular motion 
would terminate the phenomena; but, if the continuous 
mafs of the planetary body were unequally afted upon, 
owing to its fides being of different denfity, then the 
equal action of the prime mover would drive the lighter 
hemifphere round the heavier (as the Pacific Ocean round 
the old continent) ; and a rotary motion would neceffarily 
be generated, whofe axis would equalize the quantities 
of matter on each of its fides. 
Of courfe fuch an aftion, conftantly exerted on various 
bodies diftributed through fpace, would caufe them to 
vary their refpeftive motions, according to their pofitions 
in relation to each other; becaufe the force on each 
would be as their mutual pofitions in regard to the Sun. 
Hence the mutual diflurbances of the uniform motions of the 
planets. 
The motion thus created in every mafs would, from a 
like caufe, occafion each to aft on the other, in propor¬ 
tion to its bulk and quantity of matter. The Earth and 
Moon would be afted upon by the Sun ; but the Earth 
would alfo aft upon the Moon more than the Moon 
upon the Earth, in the proportion of their matter. The 
common aftion of the Sun on both would occafion them 
of neceffity to endeavour to turn on the centre of the 
quantity of motion generated by each. Hence the revolu¬ 
tion of fmall maffes round large ones. 
But, as the fecondary planets would be governed chiefly 
and proximately by their primaries, and thefe would 
poffefs a power of varying the centre of motion by the 
motion of their fluids, which would, from that caufe, rife 
in the parts prefented to the fecondary; fo the fecondary 
would not turn on the centre of its own mafs, but its 
difpofition to do fo would be deftroyed by the varying or 
accommodating energies of the primary. Hence the pe¬ 
culiar motions of a fecondary planet, and the necejfary con¬ 
nexion of thofe motions with the tides of the primary. 
Of courfe alfo, as the axis of each mafs, or of the joint 
maffes of primaries and fecondaries, would be conftantly 
turning round the phyfical axis or centre balancing their 
quantity of motion, and as the moving power in the Sun 
would be conftantly impelling that moving axis, the 
centre of denfity of the fingle or conjoined maffes would 
deferibe the orbit round the Sun, and its variations would 
tend to vary the curve of the orbit. 
The diameter of the orbit, or the radius veftor, would 
therefore be (lightly and regularly varied by any arrange¬ 
ment within the planet which enlarged the diftance 
between the centre of motion and the centre of matter, 
as a preponderance of water in one hemifphere, either 
from conftruftion or the melting of congealed maffes. 
It feems to be a neceffary fact, that the caufe which varies 
the direftion of motion, or the equal orbit of a planet, 
7 N (hould 
