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shaft is really a giant well, and the bucketsONE of the great bugbears of the coal-miner is or “tanks," as they are called-are arranged in water. In fact, it was the crying need of pairs, so that as one of them is going down the some means of ridding collieries of water that other is coming up, thus one partly counterinspired Newcomen to build the first steam- balances the weight of the other. The tanks engine in 1705; and forty years later, when are provided with spouts at the bottom, which James Watt turned his attention to steam

are closed by means of valves that open inpower, he had the pumping-out of mines as ward, so that when they are lowered into the his first object. The British coal-mines are water they are opened by the pressure of the for the most part located below sea-level, and some of them extend far out under the very bed of the ocean. In these mines, there is a continuous battle with water, and were

MINING TUNNEL not the pumps worked constantly day and night, the mines would soon be drowned out.

Fortunately, in the United States the coalmines are far removed from the sea-coast, and the coal-beds, in most cases, are not far below the surface, so that we are not bothered with

TANIS-PALLING water to the same extent as are our British

DRAINAGE cousins. However, there are some mines in

TUNNEL the anthracite regions of Pennsylvania that run down to a considerable depth and encounter a great deal of water. Strange as it may seem, the water in these mines is not pumped out. Raising water five hundred to a thousand feet with a pump is not so simple as it sounds. A suction-pump will raise water only a little over thirty feet. For greater heights of lift, a force-pump may be used, or an air-lift. In the latter case, compressed air water outside, but when they are drawn up is let into the bottom of the water-pipe, and the pressure of the water inside keeps them the air bubbles carry the water up with them. closed. When the tanks are brought up to But instead of using any such systems in deep the top of the mine shaft an automatic trip mines, the simple expedient is used of bailing opens the valves and the water pours out into out the mine with buckets. The mine a reservoir.



These tanks are enormous. Some of them are nearly six feet in diameter and almost thirty feet high over all, about ten feet of which is taken up by the spouts. Such a tank will hold about fifteen tons of water, and the tank itself will weigh eight or nine tons more. The hoisting-cable will weigh some three tons per thousand feet, so that, as it starts up from the bottom of the shaft, there is a load of between twenty-six and twenty-seven tons to be hoisted. The empty bucket running down reduces the load to about eighteen tons. A special shaft is excavated for the water-hoist, and this runs down below the mine level to form a sump. Here the water collects from a special drainage-tunnel.

Above the shaft a tall tower is built to support the pulleys over which the hoisting-cables run. The cables run back into a power-plant, where they are driven either by steam or electric power. Such is the latest adaptation of "The Old Oaken Bucket," a water-raising contrivance that dates back to the very earliest dawn of civilization.




THE TRAVELER'S TREE In front of the “Direction” at the Botanical Garden of Eala (Belgian Congo) stands a beautiful sample of Reranella madagascariensis, which, in the warm lands, is called the traveler's tree.

THE TRAVELER'S TREE AT THE BOTANICAL GARDEN As its botanical name suggests, its country of origin is Madagascar, but it may be grown anywhere under the tropics, provided the whole fabric is not as fragile as it appears, for atmosphere be not too dry. Yet it is not fre- it will stand strong winds and even hurricanes quently found, consequently its most uncom- very well, thanks to the semi-solid, fibrous mon and highly interesting particularities are material of which the stem is composed, and to but little known.

the marvelous elasticity of the leaf stems. The bearing of the tree is very elegant; its The limbs naturally get torn in time, as baleaves are disposed all in a row bending grace- nana leaves do, the new ones being still nearly fully outward; and when it is planted a little intact while the older ones are completely cut sideways on the edge of a vista, where all the to fringes, but they last sufficiently long to movements of its leaves can be observed, it perform their duty. looks the marvel it really is. Its appearance The limb of the leaves closely resembles of a half-opened fan is quite unique and so that of the Chinese banana-plant, but the striking that it is sufficient to see it only once whole differs from it in this respect, that here in order never to forget it. To produce this it is borne on a stem which is longer than the fanlike

appearance, at least twenty good limb itself, while the limb of the banana leaf leaves are required, so that young plants are starts straight away from the stem of the plant. not nearly so handsome. But twenty leaves The leaf stems end in a curved, much-widare about as much as a tree will carry, because ened-out part, the borders of which are packed older ones disappear as new ones are formed. so tightly together that from the outside they These new leaves are produced from the center seem to form a diamond-shaped, solid mass of the fan, one to the right and one to the left, from which the leaf stems spring. This, howalternately; they are disposed face to face and ever, is not so, for each lea xtends to the tree grow right up, but are gradually pushed to stem, which it embraces completely, so that it the side by newer leaves that come up. The is very securely inserted.

As these enlarged parts are curved, there acquainted this month with the beautiful remains a space between each two leaves. and more interesting constellation of PerThis may hold so much water that when one seus, the hero of mythical fame to whom we of the lower leaves is cut from a big tree, referred last month in connection with the nearly a pint of it may be found there, with legend concerning Cepheus and Cassiopeia, which an exhausted traveler may quench his the king and queen, Andromeda their daughthirst. From this fact, the tree derives its ter, chained to the rocks to be devoured by name. There is no other tree which stores the sea-monster, and Pegasus the winged water like this, which makes it one of the mar- horse that bore Perseus to the rescue. Cetus, vels of the vegetable kingdom.

you will recall, represents the approaching The traveler's tree, however, possesses monster of the deep. We have included the another property which, not unfrequently, constellation of Andromeda in our diagram causes its doom. It attracts lightning more for this month, since it is so closely associathan other trees do. This must probably be ted in legend with the constellations of Perascribed to the special bearing of the tree, seus and Cetus, though we also showed it which has no side branches, but whose leaves last month in connection with Pegasus. are all pointed the same way, in one line. The brightest star in Perseus, known as And as it hardly ever survives the stroke, it is Alpha Persei, is at the center of a curved line

of stars that is concave or hollow toward the northeast. This line of stars is called the Segment of Perseus, and it lies along the path of the Milky Way, which passes from this point in a northwesterly direction into Cassiopeia. According to the legend, Perseus, in his great haste to rescue the maiden from Cetus, the monster, stirred up a great dust, which is represented by the numberless faint stars in the Milky Way at this point. This star Alpha is, by the way, in the midst of one of the finest regions of the heavens for the possessor of a good fieldglass or small telescope.

A short distance to the southwest of Alpha is one of the most interesting objects in the heavens. To the ancients, it represented the baleful, winking demon-eye in the head of the snaky-locked Gorgon, Medusa, whom

Perseus vanquished in one of his earliest TRAVELER'S TREE STRUCK BY LIGHTNING

exploits and whose head he carried in his

hand at the time of the rescue of Andromeda. well to plant it close to a big tree that will pro- To the astronomers, however, Algol is known tect it, while, in the open, it is advisable to as Beta Persei, a star that they have found plant several specimens at some distance consists of two stars revolving about each apart so that one should not be deprived

other and separated by a distance not much suddenly of a much valued sight.

greater than their own diameters. One of HENRY VENDELMAN. the stars is so faint that we speak of

dark star, though it does emit a faint light. THE CONSTELLATIONS FOR DECEMBER

Once in every revolution the faint star passes THE eastern half of the sky in early December directly between us and the bright star and evenings is adorned with some of the finest partly eclipses it, shutting off five sixths of star-groups in the heavens; but as we are its light. This happens with great regularity considering for each month only the con- once in a little less than three days. It is stellations that lie on or near the meridian in for this reason that Algol varies in brightness the early evening hours, we must turn our in this period. There are a number of stars eyes for the present from the sparkling that vary in brightness for the same reason. brilliants in the east to the stars in the less Their periods of light-change are all very conspicuous groups of Aries, The Ram, and short, and the astronomers call them eclipsCetus, The Whale. We will also become ing variables. We can observe for ourselves


as a

this variation in the brightness of Algol by point is gradually shifting westward, howobserving it on successive evenings. At its ever, at a very slow rate, and now at the brightest, Algol is slightly brighter than the beginning of spring the sun is to be found star nearest to it in Andromeda, which is a in Pisces instead of Aries, and it does not good star with which to compare it.

enter Aries until later in the spring. Pisces, Perseus is another one of the constellations you will recall, was one of our constellations in the Milky Way in which temporary stars for last month, and we showed in that conor Novas have suddenly flashed forth. At stellation the present position of the sun at the point indicated by a cross in the diagram, the beginning of spring. Dr. Anderson, an amateur astronomer of Two stars in Aries, Alpha and Beta, are Scotland, found on February 21, 1901, a fairly bright, Alpha being fully as bright as

the brightest star in Andromeda. Beta lies N.

a short distance to the southwest of Alpha,

and a little to the southwest of Beta is GamPERSEUS

ma, the three stars forming a short curved line of stars that distinguishes this constellation

from other groups. The remaining stars in Algol

Aries are all faint.

Just south of Aries lies the head of Cētus,

The Whale. This is an enormous constellaTRIANGULUM

tion that extends far to the southwest, below ARIES


a part of Pisces which runs in between Andromeda and Cetus. Its brightest star, Beta, Diphda, or Deneb Kaitos, as it is severally

called, stands quite alone not far above CETUS

the southwestern horizon. It is almost due

south of the star in Andromeda that is farVar Mira

thest to the west, which it exactly equals in

brightness. The head is marked by a fiveDiphda

sided figure composed of stars that are all

faint with the single exception of Alpha, which S.

is fairly bright, though inferior to Beta in


Cetus, though made up chiefly of faint new star as brilliant as the pole-star. On stars, and on the whole uninteresting, conthe following day it became a magnificent tains one of the most remarkable objects in star of the first magnitude. A day later it the heavens, the star known as O'micrón Ceti had lost a third of its light, and in a few or Mi'ra (The Wonderful). This star sudweeks it was invisible without the aid of a denly rises from invisibility nearly to the telescope. In a year it was invisible in all brightness of a first-magnitude star for a except the most powerful telescopes. With short period once every eleven months. Mira such telescopes, it may still be seen as a very was the first-known variable star. faint star surrounded by a faint, nebulous markable periodic change in brightness was light.

discovered by Fabricius in the year 1596, so Triangulum and Aries are two rather in- its peculiar behavior has been under observaconspicuous constellations that lie on, or tion for three hundred and twenty-five years. close to, the meridian at this time. There is It is called a long-period variable star, benothing remarkable about either of these cause its variations of light take place in a groups, except that Aries is one of the twelve period of months instead of a few hours or zodiacal constellations, so called because days, as is the case with such stars as Algol. they lie in that belt of the heavens known as Mira is not only a wonderful star, it is a the zodiac, in which the sun, moon, and mysterious star as well, for the cause of its planets are always to be found. Some cen- light changes are not known, as in the case turies ago, the sun was always to be found in of Algol where the loss of light is due to Aries at the beginning of spring when it a dark star passing in front of a brighter star. crossed the equator going north, and the Mira is a deep-red star, as are all long-period position it occupied in the sky at that time variable stars that vary somewhat irregularly was called the First Point in Aries. This in brightness. It is visible without a tele


Its re

scope for only one month or six weeks out of The balance-wheel of a watch is moved by the eleven months. During the remainder of the four flea-power one and forty-three one the eleven months, it sometimes loses so hundredths of an inch with every vibration. much of its light that it can not be found This amounts to 3558 miles in a year. with telescopes of considerable size. Its It takes only a tenth of a drop of oil to periods of light-change are quite variable at lubricate the whole of the machinery throughtimes, as is also the amount of light it gains out an entire year. These facts make one at different appearances.

feel a great deal of respect for the little It is believed that the cause of light changes machine that works so patiently and is of Mira is to be found within the star itself. always ready to tell the time. It has been thought that dense clouds of

S. LEONARD BASTIN. vapors may surround these comparatively

GRAIN ELEVATORS OF THE CAMEROONS cool, red stars and that the imprisoned heat finally bursts through these vapors and we We are wont to think of the natives of Africa see for a short time the glowing gases below; as a shiftless lot of individuals, who take no and then the vapors once more collect for a thought of the morrow because they can get long period, which is followed again by another all the food they want off the trees and sudden outburst of heat and light.

bushes around them. But many of the AfriIt is interesting to remember in this con- can peoples are far more civilized than most of nection that our own sun has been found to be us realize. The Cameroons, who dwell in a slightly variable in the amount of light and region which was formerly under German heat that it gives forth at different times, and dominion, are very industrious and excel in the cause of its changes in light and heat are also believed to lie within the sun itself.

As in the past few months, no planets are to be seen in the evening skies.

ISABEL M. LEWIS. THE WONDER OF THE WATCH HAVE you ever thought what a marvelous little machine you have in your watch? There are at least one hundred and seventyfive different parts in the make-up of the watch. No less than two thousand and four hundred distinct operations have to be gone through during the process of manufacture. But even more wonderful are these few astonishing facts about it.

Have you ever watched a blacksmith at work and wondered how many blows he strikes on his anvil in the course of the day? On a very busy day, the number will only be several hundred. Compare this performance with what the watch does. Each day the roller-jewel of the watch makes 432,000 blows against the fork, or 157,680,000 in the course of a year. This goes on without a single rest if the watch is in good order. If a watch were to go for twenty years, it would give some needlework, weaving, basket-making and pot3,153,600,000 blows during that period. tery. Perhaps the most remarkable products

It has been reckoned that the power that of their industry are the enormous jars and moves the watch is only four times the force bottles they build out of clay. These are used in a flea's jump. We might therefore sometimes as much as fifteen feet in height. say that one watch-power is equivalent to They serve as primitive "grain elevators," for four flea-power. How small is the power in these giant bottles the grain may be stored will be gathered when it is realized that one safely, out of reach of marauding bands of inhorse-power would be sufficient to operate sects. As much as ten tons of wheat may be 270,000,000 watches.

stored in a single large bottle.



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