The first great fact to be noticed is that the planets revolve around the sun in the same direction.
These furnaces possess a large cylindrical shell (e), lined with fire-bricks, and made to revolve round its horizontal axis by means of a toothed wheel fixed on its exterior; (if) are tire-seats holding tires (gg), which work in friction rollers (h).
Also, if the axis is made to revolve at half the apparent diurnal motion of the stars, the image of the celestial sphere, viewed by reflection from such a moving mirror, will appear at rest at every point - hence the name coelostat applied to the apparatus.
Again, any plane w is the locus of a system of null-lines meeting in a point, called the null-point of c. If a plane revolve about a fixed straight line p in it, its ntill-point describes another straight line p, which is called the conjugate line of p. We have seen that the wrench may be replaced by two forces, one of which may act in any arbitrary line p. It is now evident that the second force must act in the conjugate line p, since every line meeting p, p is a null-line.
The shell thus formed is then cut along the line of the intended equator into two hemispheres, they are then again glued together and made to revolve round an axis the ends of which passed through the poles and entered a metal meridian circle.
But, as has been remarked by Dr Robert Grant (History of Physical Astronomy, p. 515), we are no more warranted in drawing so important a conclusion from casual remarks, however sagacious, than we should be justified in stating that Seneca was in possession of the discoveries of Newton because he predicted that comets would one day be found to revolve in periodic orbits.
(The wheel continued to revolve by its own impetus, and Princess Mary long remembered the dying creak of that wheel, which merged in her memory with what followed.)
The synchronous revolutions of the transmitting cylinders are effected by making one cylinder revolve slightly faster than the other; after each revolution the cylinder which is accelerated is arrested for a moment by means of a special relay until the difference of speed is accurately compensated for.
Discarding those of Uranus, in which the orbits of the satellites are highly inclined to the ecliptic, and in which manifestly some exceptional influences have been at work, we find that the satellites revolve around the primaries also in the same direction (Exceptions are Saturn ix.
There are also two vertical racks, one at each end of the casing, in connexion with - the two springs, and these actuate pinions on the axle of the drum and cause it to revolve as the springs extend.
The shafts revolve in the same or opposite directions, according as the belt is open or crossed.
In this case the two bodies really revolve round their common centre of gravity; but a very slight modification of the equations of motion reduces them to the relative motion of the planet round the sun, regarding the moving centre of the latter as the origin of co-ordinates.
When bodies revolve at different distances around a centre, their velocities must be such that the centrifugal force of each shall be balanced by the attraction of the central mass, and therefore vary inversely as the square of the v(m i v -+m 2 vz+
The absolute direction of the line of nodes changes but slowly as the earth and moon revolve; cerse"uently, in the case shown in the figure, the line M7 /Ma M6 of nodes will pass through the sun after the earth has passed through an arc nearly equal to the angle M 1 N.
But in other cases the encrusted star settles in that portion of the revolving vortex which has a velocity equivalent to its own, and so continues to revolve in the vortex, wrapped in its own firmament.
The unbalanced masses of a locomotive may be divided into two parts, namely, masses which revolve, as the crank-pins, the crank-cheeks, the couplingrods, &c.; and masses which reciprocate, made up of the piston, piston-rod, cross-head and a certain proportion of the connecting-rod.
In this way we account most simply for the uniformity in the direction in which the planets revolve, and for the mutual proximity of the planes in which their orbits are contained.
It consists essentially of two rollers either both of wood, or one of wood and one of iron, geared to revolve in contact in opposite directions; the seed cotton is fed to the rollers, the lint is drawn through, and the seed being unable to pass between the rollers is rejected.
It has been supposed that certain electrons revolve like satellites in orbits around the atoms with which they are associated, a view which receives strong support from the phenomena of the Zeeman effect, and on this assumption a theory has been worked out by P. Langevin, 2 which accounts for many, of the observed facts of magnetism.
It was probably in Paris, the chief intellectual centre of his time, that Neckam heard how a ship, among its other stores, must have a needle placed above a magnet (the De utensilibus assumes a needle mounted on a pivot), which needle would revolve until its point looked north, and thus guide sailors in murky weather or on starless nights.
Inside, with the necessary division plates for the knives to cut against, and instead of making 140 to 150 revolutions the disks revolve only 60 to 70 times per minute.
One type comprises two separate ploughs, one right hand and one left, which revolve on the beam, one working, while the other stands vertically above it.
The fillet is drawn between two little steel cylinders which do not revolve and are held rigidly in position.
As the disk is thus made to revolve, the coins are pushed forward, and falling down a shoot are received in a bag.
If the forks are not of exactly the same frequency the ellipse will slowly revolve, and from its rate of revolution the ratio of the frequencies may be determined (Rayleigh, Sound, i.
The current to be measured passes transversely across the disk and causes it to revolve in the magnetic field; at the same time the copper brake, geared on the same shaft, revolves in the field and has local or eddy currents produced in it which retard its action.
The back rollers revolve slowly, the front rollers quickly, thus drawing the rovings out into a thinner size or count.
Erasmus Darwin, the grandfather of Charles Darwin, set forth ',in' Zoonomia a much more definite theory of the relation of variation to evolution, and the following passage, cited by Clodd, clearly expresses it: "When we revolve in our minds the metamorphoses of animals, as from the tadpole to the frog; secondly, the changes produced by artificial cultivation, as in the breeds of horses, dogs and sheep; thirdly, the changes produced by conditions of climate and season, as in the sheep of warm climates being covered with hair instead of wool, and the hares and partridges of northern climates becoming white in winter; when, further, we observe the changes of structure produced by habit, as shewn especially by men of different occupations; or the changes produced by artificial mutilation and prenatal influences, as in the crossing of species and production of monsters; fourth, when we observe the essential unity of plan in all warmblooded animals - we are led to conclude that they have been alike produced from a single living filament."
For them Israel is the centre of the world, the point around which all other things revolve - every other people derives its claim to consideration from its relation to Israel - the only subject deserving attention is the extent of the Jewish nation's obedience or disobedience to its divinely given law, on which depends its prosperity or its adversity.
When this distance is compared with those prevailing in the solar system, it seems an extraordinarily small separation between two such large bodies; we shall, however, presently come across systems in which the two components revolve almost or actually in contact.
Two stars are supposed to revolve about one another nearly or actually in contact.
In Newton's method, two angles of constant magnitude are caused to revolve about their vertices which are fixed in position, in such a manner that the intersection of two limbs moves along a fixed straight line; then the two remaining limbs envelop a conic. Maclaurin's method, published in his Geometria organica (1719), is based on the proposition that the locus of the vertex of a triangle, the sides of which pass through three fixed points, and the base angles move along two fixed lines, is a conic section.
The distance of the moon can also be computed from the law of gravity, the problem being to determine the distance at which a body having the moon's mass would revolve around the earth in the observed period.
As the earth revolves from west to east the celestial sphere appears to us to revolve in the opposite direction, turning on the line j oining the Celestial Poles as on a pivot.
Let OZ be an axis, as nearly vertical as it can easily be set, round which () N C A B the entire instrument may revolve through 180°.
As they revolve these brushes engage the tea in the hopper, draw it out by degrees, and drop it into a compartment of a circular drum which hangs on one end is placed in the weights-pan of the balance, and is the only loose weight used with the machine.
The cam shaft and the cam then begin to revolve, and the flitch-plate is gradually lowered till the knife-edge bearings of the hopper are received on the knife-edges of the main measuring levers, and the load is then weighed by the levers and the spring-balance.
In the actual instrument, the paper diagram is mounted upon a drum caused by clockwork to revolve uniformly, and is ruled with vertical hour lines, and horizontal quantity lines representing gallons per hour.
If the wings were not driven at a high speed, and if they were not eccentrics made to revolve upon two separate axes, they would of necessity be large cumbrous structures; but large heavy wings would be difficult to work, and what is worse, they would (if too large), instead of controlling the air, be controlled by it, and so cease to be flying organs.
The column rules were made tapering towards the feet of the type, and the type was securely locked in on these beds so that it could be held firmly in the required position to form a complete circle, thus allowing the cylinder to revolve at a greater speed than Applegath's, which was polygonal.
If the shaft is therefore to revolve stably this force must be balanced at any instant by the elastic resistanc of the shaft to deflexion.
132, not to a point in the vertical axis, but to the end of a projecting arm C, the position in which the bob will revolve will be the same as if the 0 rod were jointed to the point 0, where its prolongation cuts the vertical axis.