The motor M is suspended from a bracket A B C by the tackle D E, and transmits the rotation of its armature by a flexible shaft S T to the terminal drill O, which can be applied at any point, and is useful in boring teeth.
The receiver of Edison was equally ingenious, and consisted of a cylinder of prepared chalk kept in rotation and a brass stylus rubbing on it.
The rotation of a disc inside the box produces a supply of static electricity, which passes in a stream of sparks between two contact-points in the open end of the stem D.
The attempt to grow cereals year after year without manure and without rotation of crops has made the wheat crops so liable to rust that agriculture is discounted everywhere near the sea.
But more important than irrigation, and much less costly, would be a better system of cultivation, the introduction of leguminous crops and roots in rotation with cereals.
Ploughing is done perfunctorily, and no rotation of leguminous crops with serials is attempted, because it is believed that there is no market in Cape Town for beans and other legumins.
He thinks the luscious emerald burseem (Egyptian clover), grown in rotation with wheat, might stock the soil with nitrogen and possibly destroy the rust in wheat which is universally complained of.
Then place the threads in same rotation on the second bridge; now draw the threads tight and with the remains of length tie on round the end of loom and fix in and around the pegs.
After cutting threads, commence to tie all threads together at one end, fix this on the nail on the spool and then place each of the threads in rotation on the notches of bridge, carrying the threads to the opposite bridge.
This suggests that the rotation is proportional to the intensity of magnetization, and not to the magnetic force.
For the magnetic metals Kundt found that the rotation did not increase so rapidly as the magnetic force, but that as this force was increased the rotation reached a maximum value.
The direction of rotation is not the same in all bodies.
We see from the equations that the rotation is very large for such a value of p as makes P = 0: this value corresponds to a free period of the ions, so that the rotationought to be very large in the neighbourhood of an absorption band.
Righi has shown that the rotation at reflection is greater for long waves than for short, whereas, as we have seen, the Faraday rotation is greater for short waves than for long.
The sign of r depends on the sign of e, hence the rotation due to negative ions would be opposite to that for positive.
The following are the values of R (when the rotation is expressed in circular measure) for the D line and a temperature of 18 deg.
Among those that produce negative rotation are ferrous and ferric salts, ferricyanide of potassium, the salts of lanthanum, cerium and didymium, and chloride of titanium.
The rotation when the light is polarized in the plane of incidence is always less than when it is polarized at right angles to that plane, except when the incidence is normal, when the two rotations are of course equal.
According to Righi, the amount of rotation when the plane of polarization of the incident light is perpendicular to the plane of incidence reaches a maximum when the angle of incidence is between 44 deg.
When the incidence is more oblique than this, the rotation of the plane of polarization is in the opposite direction to the electric currents which would produce a magnetic field of the same sign.
When the light is polarized in the plane of incidence, the rotation is at all angles of incidence in the opposite direction to that of the currents which would produce a magnetic field of the same sign as the magnet.
Boeckh: who contends that Plato cannot have believed in the diurnal rotation of the Earth, because he (Plato) explicitly affirms the diurnal rotation of the outer celestial sphere, or Aplanes.
The best of all movements is, that which is both in itself and made by itself: analogous to the self-continuing rotation both of the Kosmos and of the rational soul in our cranium.
These two facts nullify each other, so that the effect would be the same as if there were no rotation of either.
Observations of the rotation of the Kosmos 237 The Kosmos is product of joint action of Reason and Necessity.
It is this circular rotation which continues with perfect and unchangeable regularity in the celestial sphere of the Kosmos, and also, though imperfect and perturbed, in the spherical cranium of man.
The Stoic Kleanthes, in the century after Plato's death, declared that the Samian astronomer Aristarchus ought to be indicted for impiety, because he had publicly advocated the doctrine of the Earth's rotation round the Sun.
The solar nebula was endowed with a general movement of rotation in the direction west to east.
A movement of rotation occurred to his mind as constituting the principle of stability, and he deduced the necessary velocity from this consideration.
Finally, the rotationof the sun also is directed from west to east.
Here we seem to see the idea of rotation very emphatically conveyed.
It proves, too, that they have not been formed by the rotation of the earth on its axis, as might have been suspected, had all these strata been parallel with that axis.
The second feature I dislike, and strongly dislike, is the abandonment, in every instance, of the principle of rotation in office, and most particularly in the case of the President.
Opposed to the rearrangement of the land due to increased rotation caused by contraction, there has presumably been another rearrangement due to tidal retardation of the earth's rotationand a consequent lessening of the equatorial bulge.
In the triplets, however, the third star is ordinarily at least ten times as far from the other two as they are from each other, and its period of rotation sometimes runs into hundreds or thousands of years.
For example, there is evidence of a period of about twenty-seven days, corresponding to the sun's rotation and formerly supposed to be due to the moon's revolution which occupies almost the same length of time.
According to a well-established law of physics, contraction of a rotating body results in more rapidrotation and greater centrifugal force.
On the other hand, recent investigations indicate that tidal retardation has probably diminished the earth's rate of rotation more than seemed probable a few years ago, thus lengthening the day and diminishing the bulge at the equator.
The repeated contractions with consequent growth of the equatorial bulge would alternate with long quiet periods during which tidal retardation would again decrease the speed of rotation and hence lessen the bulge.
Thus, by rotation about the vertical tetrad axis a3a'3 the four upper faces are obtained; and by rotation of these about one or other of the horizontal tetrad axes the eight faces are derived.
This kind of symmetry, with simultaneous rotation about an axis and reflection across a plane, is also called "composite symmetry.
Here one cube may be brought into the position of the other by a rotation of 180 deg.
This is the hexad axis or hexagonal axis, for which the angle of rotation is 60 deg.
Since in many cases twinned crystals may be explained by the rotation of one portion through two right angles, R.
The crystal, now being dark, is said to be in position of extinction; and as it is turned through a complete rotation of 360 deg.
Ptolemy accepted the spherical form of the earth but denied its rotation or any other movement.
All the fragments having become subject to the rotation described, must, in coalescing, have imparted it to the one planet constituted by their coalescence.
Now, the condition of this mass implies a rotation about an imaginary axis--a rotation which, commencing with the absolute incipiency of the aggregation, has been ever since acquiring velocity.
Rotation of the armature in the normal direction is prevented by a stop.
The only effect of reversing the current will be to reverse the direction of rotation of the meter.
The direction of rotation indicates whether the machine be fast or slow, and the speed of rotation depends on the difference in frequency.
As described above, with the exception that the right hand trip causes a rotation of the regulator in the opposite direction.
Diagram of electromagnetic circuit of Westinghouse induction type watt hour meter, and diagram showing rotation of field.
The rotation of a meter is caused by two distinct torques, the varying meter torque, dependent on the power in the circuit, and the constant torque adjusted to compensate the initial friction.
A window through which the rotation of the disc can be observed in checking, should be provided for the same reason.
The break is horizontal, made by the rotation of a flat member edgewise through the oil.
So considerable is the rotation in the downward direction, that the normal position is generally attained before one complete lateral, or equatorial, rotation is completed.
The bottle was then corked and mounted on an upright wheel of the apparatus whereby, by means of clockwork, it could be kept in continual slow rotation in a vertical plane.
This, moreover, was the case, no matter what phase of the righting manoeuvre the Echinus might have reached at the moment when the rotation began.
The rotation of the globe thus becomes a double one, lateral and downwards, till the animal assumes its normal position with its oral pole against the perpendicular tank wall.
The downward spiral rotation would then be effected by gradually releasing the outer feet in row 1, and simultaneously attaching the outer feet in row 2 (i.
Scraped a number of places on all aspects of the animal indiscriminately--direction of advance uncertain and discontinuous, with a strong tendency to rotationupon vertical axis.
A 60-year rotationis indicated by a majority of the conditions shown.
In such a case it may often be best to utilize a first new crop of hemlock, but on harvesting this a few decades hence to burn clean and start the next rotation with fir only.
It is perfectly fair to compound for the remainder of the rotation any net profit so obtained and to set it against the carrying charges.
Destruction of young growth will stop the rotation at the time the surviving older material is harvested.
He crops about 650 acres each year, and fallows about the same area, working on a three-year rotation of fallow, wheat, grazing.
Attention will be given to improvement of wheat, soil renovation, fertilising and tillage methods, rotation of crops, &c.
The amount of the rotation depends upon the nature of the carbohydrate, the concentration of the solution, and the length of the column of solution through which the ray of polarized light passes.
In other words, glucose is "birotatory," or possesses two distinct specific rotatory powers, and the changing rotation effect in aqueous solutions is due to the change from one form to the other.
For example, the specific rotation of ordinary glucose is +52.
The orthodox answer was that day could not be called the cause of night, because it would not be followed by night if the earth's rotation were to cease, or rather to grow so slow that one complete rotation would take a year.
Rankine, the consideration of the hypothesis in question is entirely eliminated, and whether it be accepted or rejected, the whole matter is reduced to merely adding the motion of the train-arm to the rotation of each sun-wheel.
As before, let these be so connected by intermediate gearing that, when T is stationary, a rotation of A through m degrees shall drive F through n degrees: and also as before, let T in the same time move through a degrees.
Of these results, the first is explicable as being the absolute rotation of F, but the second is not; and it will be readily seen that the former would have been equally absurd, had the axis LL been inclined instead of vertical.
The sub-deltoid or sub-acromial bursa, which usually presents a single cavity and does not normally communicate with the shoulder-joint, is indispensable in abduction and rotation of the humerus.
The long tendon of the biceps may be dislocated laterally--or more frequently medially--as a result of violent or repeated rotation movements of the arm, such as are performed in wringing clothes.
Newton showed that if the earth is assumed to be a homogeneous, mutually gravitating fluid globe, its rotation will result in a bulging at the equator.
In order to test the effect of the earth's rotation on its gravitational force, the Academy in 1672 sent Jean Richer to the equatorial island of Cayenne to compare the rate of a clock which was known to have kept accurate time in Paris.
A body at rest on the surface of the earth requires some of the gravitational attraction for the centripetal acceleration of the body as it is carried in a circle with constant speed by the rotation of the earth about its axis.
If the rotating earth is used as a frame of reference, the effect of the rotation is expressed as a centrifugal force which acts to diminish the observed intensity of gravity.
Huygens also created the theory of centripetal force which made it possible to calculate the effect of the rotation of the earth upon the observed value of gravity.
When it is feasible, a rather large proportion of the entire produce of the rotation should be feeding-stuff for livestock, as soil fertility is most easily guarded by livestock farming.
The years of mowing are arranged in the crop-rotation to provide for as many harvests as promise immediate profit.
When grown in a six-years rotation with corn and oats or other small grain, it furnishes a rich sod for the corn, and the manure made from the hay helps to solve the farmer's fertility problem.
The purpose of the fertilizer in any case is maintenance or increase of fertility, and when this object has been secured, the crop may be whatever the rotationcalls for.
When the crop-rotation embraces two or more years of grass, or one of clover followed by only one of grass, it is better practice to use the manure to thicken the sod.
It will affect soils directly, as does red clover, when farmers appreciate the fact that its rightful place on their farms is inrotation with grain.
The rotation is excellent where there is enough fertility for the potato, which usually can be by far the most profitable crop in the entire rotation.
In a crop-rotation containing corn and wheat, the corn-stubble land is left unbroken until May or June, and then plowed.
The practical farmer can determine the estimate he should put upon clover only by noting its effect upon yields in the crop-rotation upon his own farm.
The legumes and grasses come into the crop-rotation primarily to raise the percentage of organic matter that the land may appropriate to itself within the rotation.
The danger of failure in case of this rotation is relatively small.
If most crops are fed on the farm, the manure is a leading source of fertility for all fields and crops, and may be used once or twice in the crop-rotation on every field.
In the same way a rotating sphere will make one complete rotation in a shorter time when its radius, which corresponds to the length of a pendulum, is shorter.
While the originally melted earth was cooling and shrinking, the rate of its rotation was necessarily increasing.
Even, therefore, if the moon at any time began to rotate faster than the earth, the earth acting on its projecting surface retarded it until the time of its rotation agreed exactly with the time of its revolution.
It was the presence of this partly fluid interior that resulted in the time of the moon's rotation agreeing exactly with the time of its revolution.
At first it spun but sluggishly, but as it cooled and began to shrink this rate of rotation began slowly to increase.
When I say that the time ofrotation is the same as the time of revolution of the moon, I do not mean that it is almost the same, but that it is exactly the same.
As the huge mass continued to shrink or contract, its rotation began to gradually increase until at last its centrifugal force was sufficiently great to cause it to bulge out at the equator, so as at last to separate a ring of gaseous matter.
