Birds and Nature, Vol 10 No. 2 [September 1901]

TOURMALINE

Early in the eighteenth century some children of Holland, playing on a warm summer’s day in a court yard with a few bright colored stones, noticed that these possessed a strange power when warmed by the heat of the sun. They attracted and held (just as a magnet attracts iron) ashes, straws and bits of paper. On reporting this strange discovery to their parents the latter, it is said, could give no explanation of the curious property, but a relic of their knowledge of it is left in the name of “aschentreckers” or “ash-drawers” which they gave the stones and by which they were known for a long time.

Such was the method of introduction to the civilized world of the mineral now known as Tourmaline, a mineral which in variety of color, composition and properties is one of the most interesting in Nature.

The lapidaries who had given the Dutch children the stones for playthings did not recognize them as different from the other gems in which they were accustomed to deal. So to the present day, although Tourmaline is considerably used in jewelry, it is rarely ever called by that name. The green varieties are often known as Brazilian Emerald, Chrysolite or Peridot, some varieties of blue as Brazilian Sapphire, others as Indicolite, the colorless as Achroite, and the red as Rubellite, Siberite, and even as Ruby.

It is only somewhat recently that these different stones have been recognized as being varieties of a single mineral species which is known by the name Tourmaline. This name comes from a Cingalese word (turamali) which was applied to the first Tourmaline gems sent from Ceylon to Holland.

At one time the name Schorl was chiefly applied to the species. This was before the means of distinguishing mineral species were as well understood as they are now, and a large number of minerals and even rocks were included under the name Schorl. One by one, however, they were distinguished by separate names until Schorl included only Tourmaline, and shortly afterward the name Schorl was dropped altogether.

In its opaque form, colored either black or brown, Tourmaline is a comparatively common mineral. It accompanies many so-called metamorphic rocks, i. e., rocks which have been changed by heat and pressure from their original condition, and is also common in granite and other eruptive rocks. As a rock forming mineral it often occurs as long, slender prisms, frequently about the size of a darning needle and radiating in all directions. The only mineral for which it is likely to be mistaken in this form is Hornblende. It can be distinguished from this in the following manner: On fusing the powdered mineral with a mixture of bisulphate of potash and fluor spar (best done on a little loop of platinum wire) Tourmaline will color the flame green, while Hornblende will produce no coloration.

The black opaque crystals often reach a large size, as some are known to be four feet in length. Both black and brown Tourmaline are usually opaque, and hence have no value as gems. The Tourmalines available for gems are transparent and have a great variety of color.

The gem Tourmalines are to be found in only a few localities. They occur in Maine, Connecticut and California in our own country, and also in Brazil, Russia and Ceylon. The crystals are usually in the form of long, slender prisms. They often have the peculiarity of being differently colored in different portions. Thus a crystal may be green at one end and red at the other, and in cross section may show a blue center, then a colorless zone, then one of red and then one of green. Some of the crystals from Paris, Me., change from white at one termination to emerald green, then light green, then pink, and finally are colorless at the other termination. In some crystals again the red passes to blue, the blue to green and the green to black.

Exactly what produces these differences of color is not known. It is known that black Tourmaline has an excess of iron, the red and green an excess of sodium and lithium, and the yellow and brown an excess of magnesium in their composition. These same differences of composition characterize similar colors in portions of the same crystal as well as separate crystals. Hence the evidence is quite conclusive that the color in some way depends on the composition. Many transparent Tourmalines, while appearing of a uniform color when viewed in any one direction, exhibit different colors when viewed in different directions. Thus, one of the long, slender crystals may appear green when held lengthwise in front of the eye, but when looked at from the end appears brown. Again, some crystals appear perfectly transparent when viewed perpendicularly to the sides of the prism, but when viewed from the end are perfectly opaque. This may be true even when the thickness is less in the latter direction. Both these properties are due to the arrangement of the molecules of Tourmaline, which is such as to make the power of absorbing light different in different directions.

The form of crystals of Tourmaline is usually that of a three-sided prism. The sides of the prism are usually marked by narrow parallel lines called striæ, and the prism may be more or less rounded by the addition of other planes.

If a doubly terminated crystal be examined carefully, it will be seen that the planes on the two ends are not alike, either in number or inclination. On one end there may be three planes, on the other six, or even twelve. If the planes on one end make a blunt termination, those on the other may make a sharply pointed one. Such a peculiarity of crystal form is possessed by but few minerals. Those possessing it are said to be hemimorphic, i. e., half formed. In such minerals it is evident that the forces of attraction by which the molecules were arranged differed in character at one end from those at the other. In other words, a separation of the molecular forces seems to have taken place, one kind going to one end and the other force to the opposite end. Now, it is a curious fact that most crystals which exhibit this peculiarity of form are also pyroelectric, i. e., become electric on heating. It was this development of electricity which caused the stones with which the Dutch children played, to pick up ashes, paper, etc., when the stones were warmed by the heat of the sun. Anyone can repeat their observation by gently heating crystals or even fragments of Tourmaline and applying them to bits of paper. The electrical attraction will often be found to be very strong, though it varies with different crystals. The fragments should not be overheated, the electricity being most strongly developed between 100 and 200 degrees Fahrenheit. A study of the kinds of electricity developed by the heat shows that positive electricity is produced at one end and negative at the other. Now, this exactly corresponds with what we have seen of the form of the crystal, and shows that the polar arrangement of the molecules producing different shapes at the two ends, also produces corresponding electrical properties. Crystal form, heat, electricity, and even light, are therefore seen to have intimate connection, and it may be that this interesting mineral will furnish us a means of learning more about these forces.

In composition Tourmaline is a complex silicate chiefly of aluminum and boron. Iron, magnesium, the alkalies, and water also enter in varying amounts into it. In fact, so complicated is its chemical nature that perhaps no other mineral has been so often analyzed or had its analyses so much discussed.

Ruskin, in his “Ethics of the Dust,” thus describes its composition: “A little of everything; there’s always flint and clay and magnesia in it; and the black is iron according to its fancy; and there’s boracic acid, if you know what that is, and if you don’t, I cannot tell you to-day, and it doesn’t signify; and there’s potash and soda, and, on the whole, the chemistry of it is more like a mediæval doctor’s prescription than the making of a respectable mineral.”

As to its hardness and specific gravity, Tourmaline may be said to be both harder and heavier than quartz, its hardness being 7-7.5 in the scale of hardness of which the diamond is 10. Its specific gravity is 2.98-3.20. These qualities fit it admirably for use as a gem. It is, however, quite brittle and even at times friable. Cracks therefore frequently cut across good crystals and spoil what would otherwise make a good gem. It is very common to find tourmalines in the rocks broken into a number of pieces and the fragments “mended” together with quartz or calcite. This has been true of the black Tourmaline shown in the accompanying plate. Scarcely any other mineral exhibits this change so often as Tourmaline, a result due probably to its brittleness and the character of the rock in which it occurs.

I have shown how one of the most remarkable properties of Tourmaline was discovered by children. It is also interesting to know that the locality of the finest Tourmalines in the world was discovered by two boys named Elijah L. Hamlin and Ezekiel Holmes. They were interested in the study of minerals and spent much of their leisure time searching for them. One day in the fall, having been out many hours hunting for new minerals, they were about to return home when a gleam of something green at the roots of a tree caught their eye. Eagerly bringing it to light, they found it to be a beautiful green Tourmaline. A fall of snow that night prevented their obtaining more of the crystals, but the following spring they returned and secured many fine gems. For many years thereafter the locality furnished gems of purest ray serene which have gone to adorn the coronets of kings and enriched the mineral cabinets of the world.

It is estimated that fifty thousand dollars’ worth of Tourmalines have been taken from this one locality. Auburn and Rumford, Me., are two other neighboring localities where good gems have been found. At Haddam Neck, Conn., fine transparent Tourmalines occur, generally green in color, and many of them of gem quality. They occur in a granite rock.

The red Tourmaline (Rubellite) from California, illustrated in the accompanying plate, is found in San Diego County of that State. The matrix in which it occurs is a lithia-bearing mica (lepidolite) of a delicate violet color. In this matrix the Tourmaline usually occurs in radiating masses. The rose color of the Tourmaline contrasting with the violet of the lepidolite makes an object which is quite a favorite with mineral fanciers, although the former is not sufficiently transparent to be used as a gem. At two other localities in the same State large transparent Tourmalines of varying colors have been found.

The Brazilian Tourmalines are chiefly green in color. They occur in connection with blue and white topaz. They are the source of the gem known as Brazilian Emerald, which has not, however, the value of the true emerald.

The Tourmalines from the island of Elba are generally red in color, transparent and well crystallized. They are, however, too small to use as gems.

The Ceylon Tourmalines occur in the gem gravels of that locality accompanying rubies, sapphires, etc., while those of Russia, chiefly red in color, come from the Ural Mountains, being found in company with amethyst, topaz, beryl and other gems.

Oliver Cummings Farrington.

THE STAR FISH

One of the most common objects found along our New England sea coast is the star fish, called by the seamen “Five-fingered Jack.” The fact of its being common does not at all imply that its habits are commonly known. The great difficulty of watching it in its native haunts has been a drawback to getting better acquainted with it, but when taken to an aquarium it has been found to be an exceedingly interesting little star. At low tide you may find hundreds of them clinging to the rocks, sea moss or on the sandy bottom, but they prefer deep water. Their color varies from a dark rich brown to a reddish, and often a chocolate shade, sometimes lighter; but no matter the shade, they are always attractive.

The upper side is slightly convex, rough and tuberculous; the under side is soft and contains all the vital and locomotory organs. Immediately upon being taken from the water the soft under parts seem to shrink away and nothing substantial remains but the upper surface. This is perforated with pores, through which the water enters to all parts of the body by channels. Very near the center is a small opening through which the water is admitted to a strong, rather elastic, tube, which is encircled by a series of rings. Now turn the star fish over and you can see that this tube opens into a ring about the mouth, while similar tubes stretch out to the arms. From these cross tubes little fibers extend, terminating in discs. These are the true organs of locomotion, and are called ambulacra. They move very slowly and are not at all clumsy, but have even been called graceful by some naturalists.

A portion of these ambulacra are made fast by suction while the rest of the body is drawn forward; then the first are relaxed and the process repeated, thus they travel in the deep waters.

It is quite evident that the five bright red eyes at the tip of each ray are of some use in helping them on their journeys; but just how much they can see is not quite known. When a large object appears before them they prepare to surmount it, often going up very steep sides and down again as easily as though on a level stretch, often standing on the tip of one ray and sometimes on the five, thus resembling a five-legged stool.

The heart, situated near the opening on the back, is supplied with a set of blood vessels. They also have respiratory organs and a nervous system, but, judging from the manner they endure vivisection, their nervous system must be of a very low order, for if they are broken in pieces the missing parts will soon grow again – in fact, they do not seem to be disturbed in the least no more than if it were a cast-off garment, and evidently go about as happy with the remaining rays as with the complete body, and, what is still more strange, the broken ray will grow a complete set of arms and a new body. This is one way of reproduction, so if you wish to kill a star fish don’t break it in pieces. The only sure way of making an end to their lives is to drop them in fresh water, when they immediately die.

It is very interesting to watch them care for their eggs. These are kept in pouches at the base of the rays, and when emitted through an opening there provided, are actually brooded as a hen her chicks, by arching the central part of the body and bending the rays down, and if the eggs are scattered they take great pains to collect them again, often traveling long distances for them.

The star fish consumes a large amount of food; you would hardly think one stomach could care for so much, but each ray has an additional stomach, and all need food. Their favorite food is the whelk, a small black-shelled, snail-like mollusk. Indeed, they eat many varieties of the mollusk.

They are also very fond of oysters. You would be interested to watch the star fish as he slowly works his way along until directly over the oyster, then folds his five arms around it, holding it firmly in place, then pushing out his stomach, through his mouth, he wraps it around the unfortunate oyster, and by the power of suction the oyster is drawn from the shell and digested and the shell cast away. You can easily see what a nuisance they must be in an oyster bed.

They are known as the opossum of the sea, as they often appear to be quite dead when they are very much alive. If you wish to be sure, put him on his back, and if alive you will soon see a number of semitransparent globular objects beginning to move, reaching this way and that. These are the ambulacra seeking to regain their normal position. If you see no motion, you may safely conclude that he is an extinguished star.

Rest H. Metcalf.

IN THE MEADOW

A butterfly with spangles gay,Met a bumble bee, one day,Where the sunshine warmly layTurning clover into hay.“Hark!” said lovely Shining Wings,“Hear how loud that blackbird sings!Don’t you think the summer bringsJust the brightest, sweetest things?“See the color of the sky;See the clouds that sail so high;See the milkweed floating by” —Said the dainty butterfly.“Smell the clover blossoms there,Scenting all the summer air;Nothing half so sweet or fair,As this meadow, anywhere!”Bumble jerked his little head,Then he rather crossly said:“Well, I like the clover red,Not for perfume, but for bread!“All the world knows that a beeMuch too busy is to seeBeauty merely. All that heCares for is utility.”Shining Wings then made reply:“Though I’m but a butterfly,Beauty’s faithful lover I,And without it fain to die.“Life itself is naught, poor bee,If it’s but utility;Sure am I ’twas meant that weShould the beauty, also, see;“Else there were no summer sky,Nor the clouds to sail on high;Else no milkweed floating by,Nor spangles for the butterfly!”Angry Bumble flew away,Leaving Shining Wings to stayWhere the sunshine warmly lay,Turning clover into hay.Sarah E. Sprague.

THE INDIAN ELEPHANT

(Elephas indicus.)

The Indian Elephant (Elephas indicus) inhabits the wooded parts of Southern Asia from the Himalayas to the Indian Ocean, and is found throughout Burmah, Siam and the Malay Peninsula. It differs from the African Elephant in having much smaller ears, a concave instead of convex forehead, smaller tusks, and in the possession of a finger on the end of the proboscis which, working against a tubercle on the lower part of the trunk, serves many of the purposes of the human hand.

The proboscis, which is an extension and enlargement of the nose and upper lip, is composed of as many as forty thousand interlacing muscles, and is capable of the most delicate and varied manipulation. At times it is used to strip twigs and leaves from overhanging trees, or again to uproot bamboo shoots or to pluck grass and plants from the ground, carrying all to the ever-grinding jaws behind. By sucking it full of water the Elephant may give himself a shower bath or squirt water into his mouth or even over people who offend him.

The presence of the trunk and tusks has greatly modified the cranium of the Elephant. Although a very intelligent animal, his brain is relatively small in proportion to his immense size. The great, rounded humps which crown an Elephant’s head are composed of bony air cells, and their function is to provide surface for the supporting muscles of the trunk. So thick are these bony processes that they will stop a rifle ball; and on the other hand Elephants have been shot through the skull without the least injury to the brain.

The tusks, which are often lacking in Asiatic Elephants, especially in the females, are the incisors of the upper jaw, grown straight out, and serve primarily as weapons, although in domesticated animals they are used to dig and lift and to carry heavy burdens. Besides these teeth the Elephant has four large molars, two in each jaw, and he is able to chew from four to eight hundred pounds of green fodder a day with them. In a wild state the Elephants wander about in bands through the forests, following their leader from feeding grounds to water, and concern themselves largely with eating and drinking and escaping from their enemies. The young weigh about two hundred pounds at birth, and attain to over eight thousand pounds at thirty years, when they have reached maturity. At sixty an Elephant is counted in his prime, and many live to be a hundred or even a hundred and fifty years old. Eleven feet is the extreme height of the Asiatic Elephant. His specific gravity is so great that in swimming rivers his whole body disappears below the surface; but this gives him no trouble, as he breathes by thrusting the tip of his trunk above the water and can surge up enough to get one eye out when he wishes to see where he is going.

The eyes are small and, probably on account of living in the forest so much, they are not very sharp-sighted. This defect is counterbalanced by very acute hearing and sense of smell. In browsing the Elephant is probably guided altogether by touch and his sense of smell; and in a dark forest even very sharp eyes are of little value either in selecting food or detecting enemies, especially in an animal with so short and heavy a neck.

The feet of an Elephant are great elastic cushions with which he passes noiselessly through the jungles. When he chooses to stand still it is almost impossible to distinguish his brown skin from the foliage with which he is surrounded. But an animal as large and strong as the Elephant does not need to conceal himself, except from man, his great enemy, and when a troop of Elephants wish to pass from one place to another they often charge through the jungles and forest, smashing down trees and vines and leaving a broad trail behind them. When disturbed or wounded by hunters they rush furiously through the thickets after their tormentors, and if they fail to catch and crush them in the first charge it has often happened that Elephants have returned and smelled them out as a dog scents a rabbit.

On account of the slow growth of young Elephants it has been found more satisfactory in India to catch wild Elephants than to breed them in captivity and wait fifteen years for the young to reach maturity and usefulness. The plan usually pursued is to build a huge corral in a tract of forest where wild Elephants roam, usually across an Elephant path. Where the path enters the corral a heavy gate is made and suspended over the way, so that it can be instantly dropped and fastened. Then, when a herd of wild Elephants wanders near enough to the trap on the gate side an army of native beaters is hastily gathered and the troop is surrounded on three sides. Each beater is provided with a tom-tom or torch, and in the confusion of shouting and torch-waving the whole herd is driven into the enclosure. At first they charge the stockade wildly, and the natives rush from side to side, resisting their attacks with fire and uproar. When at last they stand huddled together in the middle of the enclosure tame Elephants are driven in and allowed to mix freely with the wild ones. Cautiously they single out an Elephant, surround him and hold him in place, while men called noosers slip quietly down from the backs of the tame Elephants and fasten strong, soft ropes about his feet, after which he is marched out of the corral between two Elephants and tamed to work as they work, carrying heavy loads, dragging and piling timber, or perhaps marching in the splendid processions of Eastern kings.

Dane Coolidge.

THE WILD CLEMATIS

Brave Clematis, through sunny days and long,I watched thee toil to reach a leafy height,Proud of thy kirtle green, and bloom-hood white;And now when winds are riotous and strong,Thou flauntest silken plumes sere leaves among,To lead my glances from the Frost-King’s blightAnd as of old my longing eyes delight,Thou, fairest climber of the rustic throng;And I take courage by thy bravery,My much-plumed friend of tangled copse and vale,That fain would hide the mars of autumn’s hour,Henceforth I strive that others only seeMy higher self as outward graces fail,And see that self through love’s ennobling power.Jenny Terrill Ruprecht.

TOPSY

Ethel Tyler has a tame crow for a pet. It is so black and such a mischievous creature that Ethel named her Topsy.

Topsy was quite small when given to Ethel, and she has learned to say a number of words.

There is a large orchard back of the house, and Topsy seems to think this her special playground. Here she can play about and “caw” to her heart’s content.

She loves to hide among the branches of a tree, then call, “Ethel, Ethel,” expecting Ethel to come and hunt for her.

Topsy is very amusing, for there is no end to her tricks and pranks, but she can also be very troublesome if she is so disposed.

Her greatest fault is that of stealing. Small articles, as keys, thimbles, spools of thread and such things have to be kept where she cannot get at them or they will be missing.

Her eyes are quick and she is so sly that she generally gets away with the things without being caught.

When articles are missed, we know whom to blame, but it is quite another thing to find them, for she seldom uses a hiding place after it has once been discovered and her plunder removed.

There is one member of the Tyler family that has not a high opinion of Topsy, and that is Tony, Ethel’s cat.