Science Progress.

Fair Play, Volume I, Issue 26, 1 October 1894, Page 35

Science Progress.

ROCKS OF THE WISSAHICKON.

Singular Beauty of tlie Stratification of the ; Gneiss Bock.

Who has not heard of the attractiveness of Wissahickon ? . One of the foremost art critics of the United States is quoted as having said that he could not concede it to be one of the most beautiful bits of scenery in the United States, but it certainly was the prettiest. -The reader is left to draw the line between these two interpretations.

In a recent issue of Meehan’s Monthly we are told that among the chief of Wissahickon’s charms is the singular heauty of the stratification of the gneiss rock. In many cases large blocks have fallen out, so as to give the rocks a cavelike appearance. This only occurs where there is a peculiar twisting in the formation. -Of course caves to any great extent only, exist in limestone regions. The action of strong acid wears away the limestone, and in. this way miles of subterranean passage ways are formed by the dissolving of rocks. However, as in the case illustrated, hollows or caves of considerable size occur on the Wissahickon. The one illustrated is of considerable depth and is known as the Hermit’s cave. It is said that a famous astronomer of very eccentric habits many years ago made his home there. The figure standing at the mouth of the cave represents one of the. arctic explorers who was on the relief expedition in the interest of Lieutenant Peary. The cut here presented reproduced from the paper quoted.

What Is Electricity?

Mr. S. F. Walker answers this question as follows in an electrical journal: “As fat as the writer is able to understand the matter now, electricity.is simply the motion of the molecules of the different substances which are the subjects of electrical action, just as heat, light and sound are, and the only difference between

these forces is the rate of the motion. The

motion ofsound, as we all know, is comparatively slow. That of heat and light is very sapid. That of electricity would ap-

pearbyße somewhere between the slow mo-' tfon of sound and rapid motion of the heat ■ waves, whose motion is slowest—that is, 1 slower than that of light. • . “And it would appear that the wonderful adaptability which electricity shows for svery kind of work is due entirely to the position which its rate of motion occupies in the scale of the energies. It would also appear that the reason this wonderful agent lay dormant for so many ages and is even now only partially developed, is very largely, at any rate, because we have no sense which responds to the particular periods of vibration comprised within the electric range."

Telephoning From Under the Water.

The telephone has lately been arranged for the use of divers. A sheet of copper is used in place of one of the glasses in the helmet, and to this a telephone is fixed, so that the.diver, when at the sea or river bottom, has only to slightly turn his head in order to report what he sees, or receive instructions from above, says The Industrial World.

An Experiment In Pliyslea.

When wo look nfc uny submerged object we all know that, in consequence of the phenomenon of refraction, ic appears above the place it really occupies. This is the reason why.a walking stick plunged into Water looks U 3 though it were broken.

Here is a corresponding experiment: Place a bright coin at the bottom of an earthenware ba&in, or any other convenient receptacle (a gold £2O piece will do), and get your spectator to lower his head until his eyes have struck a line that runs from the nearest edge of tire coin to the rim of the vase. At this instant it is iiq£ the coin itself that the observer beholds, but its image, created by refraction. The looker on not stirring from this position, you may announce to him that you will cause the piece to disappear by sucking it up through a syringe.

You have only now to extract the water from the vase, either drawing it off by a siphon or syringe. The liquid once gone, the spectator will no longer see the coin, which is hidden by the wall of the receptacle, Poor water in again and the coin will reappear.

Boring wells by electricity is now in order.

Ui'mhic—Mnrrltttre. “Help!” I The Rlrl who was drowning shrieked wildly. Her voice was borne across tho waves ' o the man on the bcacb. “Help! Help!” He shook bis head. "Impossible,” heanswered.iisinghiahftnd for a speaking trumpet. "Consider the disparity in our ages, and, besides, what would your folks say?” Presently all was still save tho murmur of the water as it rippled against the strand. —•Detroit Tribune.

By Merest Chance

It was a narrow escape. The strong man shuddered ahcl wiped the beads of perspiration from his brow, “Good heavens!" lie said. “Another moment and then”——

It was several momenta before ho recover ed sufficiently to resume Ids task. For once uguin be Imd come within an '► ace of dipping thu mucilage brush intho ink.—Truth.

Distronning.

“Great Scott, nnui,,what tut). you doing with four ularm docks in your room?” "I want to try ami get a little sleep.” “How can that help you!'” “My wife and baby have gone fora visit, and everything is so blamed quiet I can’t close my eyes.”—Chicago Inter Ocean.

One For Each Year.

: Uncle Treetop—That heifer Is 2 year* old. City Niece—How do you know? “By her horns.” “Oh, to be sure. She has only two.”— Life.

Their End.

Old Woman—l am sorry to hoar little boys uho hucli bud language. Hnvo you thought what becomes of little boys who* use bud language? Street Urchin—Yes. Ley becomes boss oar drivers.—Brooklyn Life.

A Half Learned Lesson.

Teacher—Why wok Lot's wife turned into a pillar of Haiti' Boy—For looking back, “Yes, but why did ehe look back!” “I—l guess «orao other woman passed her.”—Good News.

How She Explained It.

! . Mr. Sappy—Yaaa, I can drink lots of wbi* ky and not feel it. - , She—lt mutt go to your bead.—Troth, j