The main cause of the destruction, the migration, and the extreme modification of animal types, appear to be change of climate, chiefly depending upon oscillations of the earth's crust.

These oscillations do not appear to have ranged, in the Northern portion of the Northern Hemisphere, much beyond 1,000 feet since the commencement of the Tertiary Epoch.

The temperature of deep waters seems to be constant for all latitudes at 39°; so that an immense area of the North Atlantic must have had its conditions unaffected by tertiary or post-tertiary oscillations.

It has been suggested that they are due to changes in the weather of such a slight character that, "our nerves are incapable of appreciating them, or the mercury of recording their accompanying oscillations.

The normal is rather a mean level about which oscillations to and fro, round and about, are constantly taking place, but which itself is reached only by accident, if at all.

It was briefly as follows: If a copper disc be rotated above a magnet, the needle tends to follow the plate in its rotation; or, if a copper plate be placed at rest above or below an oscillating magnet, it tends to check its oscillations and bring the needle quickly to rest.

Here we have a simple basic experiment in wireless telegraphy, which, briefly considered, consists of means whereby oscillations or waves, set up in free space by means of disruptive discharges, are caused to traverse space and produce various effects in suitably constructed receptive devices that are operated by the waves as they impinge on them.

Foster, Isochronous Oscillations in a resisting medium, Observations on a strange piece of Iceland Spar.

The officers, who divided the heritage of the great general, gradually settled their differences, and a system of equilibrium was established, of which the very Oscillations manifest some sort of regularity.

When I was nearer her, I would see her peer across and upward toward Pera, as if that were a remembered land-mark, and would note the perpetual aspen oscillations of the long coral drops in her ears, and the nimble ply of her limbs, wondering with a groan if Pera was our goal.

In fact, minor oscillations are continually being observed, and this volcanic action takes place all along the fault, where lay the stores of petroleum and naphtha, from the Caspian Sea to the Pamir plateau.

Consequently, in a dynamometer in this simple form more or less violent oscillations of the weights are set up, which cannot be directly controlled without impairing the accuracy of the dynamometer.

Had I not interfered with it, it would have repeated its journey, time after time, each trip of shorter extent, like the diminishing oscillations of a pendulum, till it finally came to eternal rest at the centre of the sphere.

With what anxiety he observes, studies its oscillations!

These oscillations acquired sufficient amplitude to cause the superstructure to gradually move upon its rollers until the latter

The modification introduced into the balance consists in the displacing of the center of gravity of the beam in such a way as to diminish the sensitiveness, and consequently to obtain a much greater velocity, and then, by optical means, to considerably increase the amplitude of the oscillations.

Instead of the oscillations being observed through the microscope, they are projected upon a divided screen forming a dial, the division of which is seen by transmitted light.

He wondered that a man who had been apparently accustomed to the terrible dangers of the seas, should be alarmed at the gentle oscillations of a stage-coach.

Theory of oscillations.

Howik kept it steady, notwithstanding those rapid and frightful oscillations.

Rapid oscillations of the barometer should never be interpreted as presaging dry or rainy weather of any duration.

Now, just toward the 20th of February, the oscillations of the barometrical column began to preoccupy the young novice, who noted them several times a day with much care.

The wind kept in the condition of a stiff breeze all the time, and certain oscillations of the barometrical column indicated that it tended to freshen.

I tie up a guinea-pig to the tabouret, pure Louis XV., the little beast struggles and squeaks, the snake, his black, bead-like eyes are fixed, how superb are the oscillations...now he strikes; and with what exquisite gourmandise he lubricates and swallows.

Near the vortex there are usually marked oscillations.