Part 11

Next take two pieces of wood, fifteen inches square and half an inch thick; in the center of one cut a hole twelve inches in diameter, while in that of the other cut another round hole only ten inches across. In Fig. 4, which represents a section of this microscope, _g_ is the central board of the screen, marked _a_ in Fig. 1; _h_ is the piece you have just made, with the central opening twelve inches in diameter; and _i_ is the second piece, which measures fifteen inches square, but has a hole of only ten inches diameter in its center; _d_, which has a dotted surface, to distinguish it from the frame-work, is the large disk (Fig. 2), which, you remember, is just twelve inches in diameter, and, consequently, will exactly fit the opening in _h_; if these edges are rough, sand-paper both with a coarse quality first, finishing them off with a finer kind. When _d_ is in position, and moves easily but not loosely in _h_, place _i_ over it and fasten it in place with screws, passing through _i_ into _h_; but _h_, of course, must first be strongly nailed or screwed upon _g_.

You will now see that by turning the handle, _f_, the position of the mirror, which is fastened to this disk, can be easily changed so that it shall face in any direction, while by drawing the wire, _e_, it can be turned so as to reflect the sun’s rays through the lens, _a_, from whatever quarter of the heavens it may be shining. This double adjustment of the mirror and lens enables you to throw the rays of the sun through the opening in upon the object, _o_, at any hour of the day. As the mirror is adjusted in Fig. 4, the sun must be very low, as its rays, to strike the mirror, would necessarily be nearly horizontal.

The lens, _a_, should be held in place by two pieces of whalebone, bent around on either side of it, at the edge of the opening in _d_; this lens is four inches in diameter, and has a focal length of nine or ten inches; its adjustment had better be left till everything else in the microscope has been finished. Fig. 5 shows the appearance of this when completed.

As the outer part of the work is fitted, we will now turn our attention to the other, or inner, side of the screen. In Fig. 4, the board _j_ is eighteen inches long by ten inches wide, and half-an-inch thick. In the middle is a small circular hole, one and one-half inches in diameter. This is fastened to the middle board, _g_, by the four horizontal posts, _p_, each six inches long.

Now take a square piece of half-inch board, five inches across, cut a circular hole two inches in diameter in the middle, and fit into this hole a pasteboard tube four inches long, which is painted black on the inside. The edge of the circular hole in _j_ should also be black. In Fig. 6, which represents this board, you will notice two cleats, _l l_, fastened to the back of _k_; these are also made of half-inch wood, and are five inches long by one wide. In Fig. 4, the position of _k_ and _l_ is seen in connection with the longer piece, _j_; the center of the openings in _j_ and _k_ should form one and the same horizontal line. The opening between _l_ and _l_ is for the glass slides upon which the objects to be examined are placed.

After these parts are fastened in their proper places, make a pasteboard tube, with a black inner surface, as represented at _n_, about four inches in length, and inclose in one end two lenses, each one and one-half inches in diameter, and each having a focal length of four inches. Fit this tube in the one marked _m_. Now, having everything in place, fit in the lens, _a_, so that it will send the rays of light directly through the hole in _j_ upon the object in _l_, and fasten it securely in place with your bent whalebones.

The screen upon which the image is thrown can be the opposite whitewashed surface of the room, if by a proper adjustment of the tubes the image can be made distinct, or it can be a sheet stretched over a frame-work of light wood; the latter is preferable, as it can be more easily brought in focus. Of course, in this form, as in any other “magic lantern,” the nearer the screen to the lantern, the longer the tubes _m n_; but the image, which is smaller, gains in brilliancy of illumination, while with these conditions reversed, the results are the opposite; a larger image, but less bright in appearance. The same light being spread over a larger surface is necessarily less strong.

SOME OBJECTS FOR THIS MICROSCOPE.

The objects which can be examined by aid of this instrument are many in number, and can be readily prepared by simply inserting them between two pieces of glass, sufficiently small to slide in the opening _l l_, and pasting bits of brown paper over the edges to hold them in place.

In this manner the legs of flies and mosquitoes, the heads of the latter with their venomous sting; hairs of the dog and cat, also from the human head; tiny sections of human skin; down from the butterfly’s wing, obtained by dusting off a few of the tiny particles upon a glass plate; the pollen from different flowers; spores of the puff-ball and tiny grains of dust, all make very interesting subjects for study, when magnified and thrown upon the screen in the darkened room.

One of the most interesting experiments with this form of the magic lantern is made by throwing the image of a drop of some solution, like sulphate of copper, upon the screen, and watching the process of its crystallization; sulphate of copper and of iron; hyposulphite of soda, which latter may be colored by adding a very little permanganate of potash to the solution.

The eels in a drop of vinegar, drops of stagnant water, and the larvæ of the mosquito are also interesting objects, when viewed by the aid of this powerful magnifier.

―――――◀▶―――――

SEA-MOSSES.

No boy who has lived on our coast, or, indeed, who has spent much time near the sea, could have failed to notice and admire the beautiful feathery mosses which sway about so gracefully under the surface of the water. The most delicate mosses are not found upon the open sea-beach, but in the more sheltered bays and inlets near the coast, and one who has never given them especial attention cannot fail to be impressed by the great variety of form and color to be found within a small space of water. Ranging in color from the palest pink or straw to the deepest purple or brown, and from the lightest sea-green to the darkest shade of olive, they are capable of being arranged in most beautiful bits of coloring, while the delicate, fine specimens, united with the coarser varieties, add to the effectiveness of the whole. To gather and arrange these mosses is not as difficult a task as most people imagine. Any boy can, with a little care, make a fine collection, which would be valued very highly by some inland friend who cannot reach the sea-shore every year, or perhaps not more than once or twice in a lifetime. If any of you, my boy readers, have any such friend, do not fail to collect a quantity of the mosses common to the waters near you, and arrange them on cards for their preservation. In gathering your mosses have an old tin can filled with water in the bottom of the boat, and after detaching from the stones, throw them immediately into the can. When you get home they can be left in the can of salt water over night, if you have not the time to attend to them at once; or they may be put into a basin of fresh water, and left for awhile to wash away the salt and sand that remains on them. When they seem perfectly clean, take two or three carefully up on a bit of paper and throw them into a basin of clean water.

Now the delicate part of the process is reached. Have a number of square pieces of unglazed paper at hand—ribbon paper is very good for the purpose—and thrust them carefully into the water under the bit of moss you desire to take out. With a long, slender darning-needle carefully arrange the tiny filaments, so that they shall form a graceful composition, and raise the card carefully from the water. It is not necessary to exercise as much care with the coarser “silver mosses,” as their more wiry branchlets naturally assume graceful positions, and the water flowing from the surface of the card does not so easily disarrange their positions. When all the mosses have been taken up on cards, fasten each to a table or shelf to dry. This is done by driving a pin through one corner of the card into the edge of the shelf or table, and allowing it to remain undisturbed until both the moss and paper are perfectly dry. They may now be mounted upon cards prepared for the purpose, and their names, with the locality where they were found, neatly written beneath; or they may be preserved in a case or frame.

The illustrations show two different arrangements of sea-mosses for the frame. In the first, that seen in Fig. 1, they are glued upon a background of fine white cardboard, one layer superimposed above another, until they extend forward from the card for an inch or more. Their stems are finally covered by a small, well-striped scallop-shell which has been washed clean and varnished. It is perhaps needless to add that the effect is very pretty. The “silver mosses” are best adapted for this arrangement.

The design given in Fig. 2 is quite grotesque in its appearance, and appeals rather more to the average boy’s taste than the former arrangement. Red and brown mosses are used entirely, unless the effect seems too somber, in which case a little “silver moss” may be introduced on the back to lighten it a trifle.

Tiny baskets, made of pretty scallop-shells nicely fitted together and varnished, are often filled with the coarser varieties of moss, and are very pretty; but if they are unprotected from the dust they are soon destroyed, and unless covered with a glass case or inverted thin plain glass tumbler, they hardly pay for the trouble of making.

―――――◀▶―――――

ANTIQUES AND HORRIBLES.

This is another of the mechanical toys which was common during my childhood. The whole affair is so simple that a small boy could make it, in a less finished form at least, and the most sullen little fellow in all the land could not fail to be amused by the grotesque procession of clowns and hobgoblins, kings and countrymen, birds and fishes and animals, whose names no naturalist could tell, and whose like was never seen on this earth before. This procession travels on and on, as long as the crank is turned. The above illustration gives some idea of a few of the many members of the band, but any boy at all ingenious, will see that he has a variety—the more grotesque and outlandish the better the effect. Fig. 2 shows a section of the machinery; the box-like covering is removed, and the frame-work exposed to view. First procure a board, _a_, about twenty by eight inches; next two rollers upon which the band is to turn, for you must have seen that these little images are made of thin cardboard, attached to an endless band of strong cloth. These rollers should be rather larger than broomsticks, and held in place by four uprights, _c_. Only two of these can be seen in the cut. A table, _d e_, extends between the rollers and is supported by four legs, _f_, which should be of sufficient length to make the top, _d e_, come just below the upper section of the band, _g g_ are boards, the same width as the bottom, _a_, and of sufficient height to make a good foundation for the top, and to allow free passage of the procession. None of the figures should be much over three inches in height, and none should be attached to the cloth in more than one place; that is, by only one foot, as they would be unavoidably torn in passing over the rollers if more firmly fixed. The top and front are of pasteboard, and the whole exposed surface is covered with pretty wall-paper. On the right roller at the back end, fix a small crank, or handle, and the machine is started by turning this. When about to give a grand exhibition, be careful to turn in the right direction, and not set the whole procession running backward, as you might easily do if unobserving or forgetful. The images are much more amusing if painted in bright colors. Use plenty of blue, red, yellow, black, and white paint, with a touch here and there of rich green and purple; and you may perhaps almost make your audience believe that Fourth of July is here again, and they are viewing the “Antiques and Horribles” through the large end of a spy-glass.

―――――◀▶―――――

THE MUSICAL CHICKENS.

One of the most pleasing toys for children, which may be counted among those made by boys themselves, is this little coop of chickens. Make a box like Fig. 1, leaving off the top and back boards until the works are placed within it. The little bars which separate the chickens are thin strips of wood. In Fig. 2, _a_ represents one of the chickens, which is also made of thin wood and painted yellow; a hole is made at _b_, to allow the passage of a strong stiff wire, upon which the chickens turn, and by which they are also kept in place. At the end, _c_, of each, a strong piece of linen thread is tied through a small hole bored for the purpose, and each line is caught to a separate nail, driven in the bottom of the box, just below the chicken, in such a manner that when it is drawn tightly in place it will just touch the roller _d_. Fig. 1 shows just where each chicken is placed, and how far their heads protrude through the bars. The ends of the wire, _b_, which holds them in place, can be fastened on one side by simply pushing one end into a hole bored partly through the wood to receive it; the other should be slipped into a groove made for it, and fastened in place by a wedge nailed just above it when in position. Fig. 3 shows the roller in full, and the little blocks or cams which are placed along its surface. These little cams are made of wood, not more than three-eighths of an inch thick, and are placed at such distances from each other along the roller that the middle point of each shall come opposite one of the threads.

Between these blocks, but so situated that they will not come in contact with any one of the threads, are little quills, driven into tiny gashes made in the roller. These quills are an inch long, and should all be of the same length. One end of the roller is fitted with a crank, while the other is fastened in place by a wooden pin or long nail. Below this, at either end of the box, is a curved bridge, _e_, into which grooves are cut and slender brass wires drawn very tightly, as seen in a violin. The curve made by the wires, however, is unlike that in the above-named instrument, being concave instead of convex. Now it will be seen that by placing the roller in such a position that the quills will strike the wires with some force as the wheel revolves, a constant tinkling sound like that of a toy piano is the result; and at the same time, as the little blocks come in contact with the strings, they push the thread backward, and in so doing lower the point _c_, and consequently raise the head of the chicken. The top of the extension in front of the bars is made of thin board and painted green, while a slight sprinkling of yellow over its surface represents the meal the chickens are supposed to be eating. The remainder of the box may be painted to suit the fancy of the maker.

―――――◀▶―――――

CAPTAIN S.’S PEG PUZZLE.

One bright summer morning, which seems but a short while ago, unless I stop and count the years that have passed since then, we children were invited to take a sail across the bay with one of the kind-hearted old captains who owned a trim little cat-boat, which her owner was wont to boast would beat any other craft of her length in the harbor. But there was not much chance of beating anything on the morning of which I write, for, although a light northerly breeze was stirring when we intended to start, the girls of our party took so much time in which to get ready, that by the time we were fairly under way we were scarcely able to fill our sail. However, we managed to make some little headway, and in the course of two hours reached the beautiful rocky point covered with its grove of fine old trees, which, but for the delay in starting, would have been reached much earlier in the day. This point was quite a favorite spot for excursionists, and was hailed with delight by most of our party. We boys, however, cared more for the little _Sea Dog_, and the companionship of old Captain S., than for the walks on shore. So, claiming our full share of the good things packed in the baskets stowed away in the cabin, we decided to remain on board and share our picnic with the captain on the bay.

After all were on shore, and the hampers had been taken to the grove, we hoisted the sail and made for deeper water; but there was no wind, and we had to content ourselves with looking at the glassy surface around us, and feeling that we were in a boat away from shore, even if not in rapid motion. We ate our lunch as we listened to a delightful story told by the captain, of how his ship was once chased by a pirate, and only escaped through the timely interposition of a snow-storm. We next tried our hands at the oars and rowed some distance further from the land. Finally, as we were about to return for the others of our party on shore, a small piece of wood Fred found on the cabin floor changed the current of our thoughts, and we saw for the first time the little device I am about to describe. This bit of wood which he had picked up was a thin strip of a cigar-box cover. In one end was a circular hole about an inch in diameter, in the middle was a square hole of the same diameter, and at the extreme end was still another opening, in the form of an isosceles triangle, the perpendicular being of the same length as the side of the square.

When Captain S. saw the piece of wood he challenged us each to make one peg which should exactly fit all three holes. “But it can’t be done, Captain,” we both exclaimed at once; “the holes that have corners couldn’t be fitted with a round peg, and the peg large enough for the square would be too large for the triangle,” continued Fred, as he examined the openings more carefully. “But it can be done,” answered Captain S., with a peculiar kind of chuckle he always gave when very much pleased. “It can be done, for I have done it hundreds of times.”

He had done it hundreds of times; had made one peg which should fit a round, a square, and a triangular hole, and fit them nicely! How was it to be done? We thought it over, and tried to study it out; we even took out our jackknives and whittled away at an old broken thole-pin which lay in the bottom of the boat. But we couldn’t make it work; there were always the corners to be filled, and little spaces would be left if we tried to compromise, and make the pin less round as it increased in length; then the triangle! that wouldn’t accommodate itself to any shape we could devise. We whittled away for over an hour, now and again receiving a little encouragement from the captain, who greatly enjoyed our successive failures. During the meantime a brisk south-west wind had sprung up, and we were bounding over the water at a delightful speed; but we paid little attention to the sail; in fact, we hardly knew we were moving at all, so intent had we become to solve the mystery. After the others of the party came on board, we soon fired them with our enthusiasm, and every bit of available wood and every jackknife was brought into use. But not one of the party was bright enough to hit upon the right shape. I shall never forget the fun made of us by the girls—not one of whom, by the way, could sharpen a lead-pencil decently—when the captain finally showed us how the thing was done. Asking one of the older boys to take the helm, he picked up a bit of wood we had thrown aside as too small, whipped out his jackknife, and in less time than it takes me to write it, had the peg made and fitted to the holes. How he made it fit so well in so short a time has never ceased to be a source of wonder to me; but probably the practice of years, while off on lonely whaling cruises, had something to do with his dexterity.

He first whittled out a cylinder, which exactly fitted the circular hole; then he cut it off, so that its length should be the same as the diameter of the square (see Fig. 2). Now, by putting this sideways into the square opening, it fitted it perfectly. Lastly, leaving the base of the cylinder undisturbed, he cut away from either side until he had a shape like Fig. 3, which, when looked at from another point, presents the appearance of Fig. 4, and would, of course, perfectly fit the last and triangular opening.

―――――◀▶―――――

SLATE GAMES FOR CHILDREN.

A slate is one of the most useful presents which can be given to a child. Long before the little hands can fashion letters, or the infant mind comprehend them, the baby fingers can make marks and scratches upon the smooth surface and derive considerable amusement from the exercise.

As the little one grows older, these meaningless scrawls gradually change to more intelligible forms, and then it is that the “Tit-Tat-To,” so very old, and yet so delightfully new, to every little girl or boy in their turn, comes into play.

TIT-TAT-TO.

This game is played on a figure similar to the above, made on an ordinary slate. The players alternately mark in the figure, the one a cross, and the other a nought; he who first obtains a row, either horizontally, perpendicularly, or diagonally, wins the game, and calls out the following rhyme:

“Tit-Tat-To, my last go; Three jolly butchers all in a row.”

The object of each of the players is equally to obtain such a row and to prevent his opponent from obtaining one.

AIR, EARTH, OR THE SEA?

This game—which is sometimes called _Birds, Beasts, and Fishes_—is instructive as well as interesting to children who have some slight knowledge of natural history. It is played as follows: Two boys take their slates, and each writes down the first and last letters of the name of some bird, beast, or fish, first stating whether it belongs to the air, earth, or water, or from which category the name is selected, and puts a cross for each of the intermediate letters. For example: James writes upon his slate T × × × r, and remarks, as he passes it to his companion, “the earth.” Charles selects a bird and marks upon his slate as follows: E × × × e, saying, at the same time, “the air.” They exchange slates, and each tries to guess the name of the beast or bird indicated, and fills up the blanks accordingly. It is evident that those indicated above are respectively tiger and eagle.

TURKS AND RUSSIANS.

The slate should be divided into three divisions, the top and bottom divisions each having a small compartment marked off therein, as shown in the annexed diagram.

One of the two end divisions should be allotted to the Turks, and the other to the Russians, and marks put therein, to represent the soldiers of the respective nations.

Each player having provided himself with a well-sharpened pencil, the game is played as follows: The players decide the order of play, and the first selected being supposed to be a Turk, places the point of his pencil at the spot marked in the smaller compartment of the Turkish division of the slate and draws it quickly across the slate in the direction of the opposing army.

The pencil will, of course, leave a line marking its track, and all the men of the opposite side through which the track passes count as dead. Each player plays alternately, and he wins who first kills all the men on the opposite side.