At the pit end, the chute is solidly constructed with a concave f.l.a.n.g.ed surface placed on the top of the kick-back. It conforms to the downward curve of the latter, but the rail work begins at the top of the incline and extends back to the newel post at the bowler's end of the alley. The f.l.a.n.g.es easily accommodate the b.a.l.l.s when placed on the chute by the pin boy.

The newel post is not made of a solid block, but is built up, being veneered on the inside, as well as on the outside, to make it impervious to atmospheric changes. The top contains a sponge cup to moisten the fingers of the bowler.

[Ill.u.s.tration: CROSS-SECTION OF BOWLING BED SHOWING STEEL CLAMP]

The rails form a semicircle at the post, with the ends of the arc pointing down the alley. A tightly stretched leather strap extends horizontally from the upper end of the arc back to the post, where it is fastened with a swivel screw. Half way up, from the points of the arc, a second rail, _i. e._, the "receiver," is built, with sufficient s.p.a.ce between it and the strap to allow the pa.s.sage of the largest size ball.

With the momentum gained by rolling down the incline of the kick-back, the ball rolls back on the inside of the curve until it strikes the strap, where its course is stopped, and it drops on the receiver, ready again for use by the bowler.

In beginning the construction of an alley, the mechanic lays the leveling strips on which the bed is to rest. These are set at right angles to the direction in which the bed is to lie, and must be spirit-leveled for accuracy, and firmly fastened to the foundation. A strip of cork carpet is then laid the full width of the alley and extending the entire length of the bed. This is to reduce to a minimum the sound of the b.a.l.l.s dropping on and rolling down the bed.

On the leveling strips at the extreme side of where the bed is to lie, a 3 x 1-inch maple strip is laid, widest side downward, with its finished one-inch edge nearest to the gutter. One end of this strip marks the extreme end of the approach. The other end of the strip is continued by adding other strips the full length of the bed. When these have been carefully squared to the exact direction the alley is to run, they are fastened to the leveling strips.

The next strip, also of maple, is tongued into the lower one, but its continuous length extends only about five feet beyond the foul line, or about eighteen feet from the approach end.

A bowling bed cannot be laid as an ordinary floor. It is built upon its side and when finished resembles a wooden wall about seventy-five feet long four inches high and three inches wide.

The approach end of the bed, approximately eighteen feet long, is constructed of maple, with each alternate strip of the 3 x 1-inch bed stock about eighteen inches shorter. The pit end of the bed is similarly constructed for a distance of about six feet. The s.p.a.ce between is filled in with the pine strips of the same dimensions, and the alternate long and short strips at the inner ends of the approach and pit ends form mortices into which the pine dovetails.

[Ill.u.s.tration: PIT END SECTION OF BOWLING ALLEYS]

The wear on the bed occurs where the bowler walks and drops the ball and where the ball strikes the pins; hence the hard maple. The interior is filled with pine, which is softer, because it retains a higher polish and prevents the rolling ball from b.u.mping; thus throwing it from its proper course.

The bed is thus built up for its continuous length, strip by strip, the tongue of one strip fitting into the groove of the other, and both nailed firmly together, until the proper width (while being built, the height) is attained. When the bed is finished, the strips are clamped with steel clamps, the turned-up ends of which firmly grip the sides of the bed, thus preventing warping or spreading. While the bed is still in this upright position, a one-inch slot is cut across where the foul line is to rest, and holes are bored through the bed. A black composition strip, _i. e._, the "foul-line," is inserted in the slot and bolted through the holes to the bottom of the bed.

At the pit end, circular slots are cut and holes bored for the purpose of countersinking and fastening the "pin spots." The latter are of the same substance as the foul-line and all are sunk flush with the surface of the bed.

This--clamping and fastening--explains the necessity for building the bed on its side.

It is now ready to be placed into position. It is merely toppled over, face side upward, clamped side underneath. So exact has it been built, according to specifications and alignment, and the ma.s.s is so heavy, that the dead weight makes it lie where it falls and only the slightest adjustment is necessary.

The height of the leveling strips, plus the height of the bed, lift its surface about six inches from the foundation floor. At the pins end of the bed, this forms one of the sides and the bottom of the pit. The bottom is floored with maple and covered with a specially prepared pit mat, durable, yet soft, so as not to damage the b.a.l.l.s and pins falling upon it. The back and sides of the pit are formed by the kick-backs, braces and cushion.

After the kick-backs are placed in position, the gutters are laid, and then the return chute railway is laid, between and slightly above them.

At the approach end of the bed the newel post is firmly fastened to the foundation, and the floor that is laid above the latter and flush with the surface of the bed serves to brace the post, making it immovable.

The curved end of the chute and the receiver are then added.

The bed is then planed its entire length, sandpapered, sh.e.l.laced and polished. The remainder of the woodwork is finished in its natural color except the gutters, which are stained mahogany and sh.e.l.laced. They are thus stained, not only for artistic effect, but to clearly define the outer edges of the bed--a matter of great importance to the bowler when trying to knock down the two outer pins in the third row.

In making the pins, the best selected logs are sawed into blocks about 2 x 1 feet. These are placed in a lathe and gouged out, forming the pin in the rough. They are next turned down to size and selected for quality and weight, after which they are kiln dried and receive a final turning to perfect their formation, then smoothed and finished.

[Ill.u.s.tration: BACKUS AUTOMATIC PIN SETTERS]

The Backus pin-setter is almost human in its operation. The old way was to hire boys to set up the pins on the spots and return the ball via the return chute. The pin-setter relieves the boy of the major and most time-consuming part of this work. A frame holding the machine is set up over the spots. It is placed so high that it does not interfere with either the flying pins or the rolling b.a.l.l.s.

As the pins are knocked off into the gutters, or the pit, the pin boy picks them up and lays them flat on their sides into the pockets at the top of the machine. When a "frame" is rolled those pins standing on the alley remain there and the machine is lowered by a balance weight controlled by a lever. As it descends the pins are automatically set on end, and when they rest on the spots on the alley the machine releases them and springs up to its original position.

Wooden b.a.l.l.s for bowling were never satisfactory. They wore out too easily and never retained perfect rotundity. Fortunes were spent in experimenting with other materials until at last the famous "mineralite"

ball was perfected.

Its composition is a trade secret, but its chief ingredient is rubber.

First the composition is rolled into sheets. These are then molded and later vulcanized, being subject to terrific pressure. The b.a.l.l.s are then smoothed and polished.

As it is impossible to make a perfectly round ball and have the weight equally distributed, the ball can not roll true; an ingenious device overcomes the difficulty. The ball is set in a basin of mercury, where it floats. Naturally, the heavier side of the ball swings to the bottom.

On the top, diametrically opposite to the center of weight, a chalk mark is placed on the ball and it is then lifted out of the mercury.

Diametrically opposite to the chalk mark a small hole is punched into the ball to indicate the weightiest point. Directly beneath this is stamped the trademark of the firm.

Having ascertained the proper distance apart the finger holes are to be bored, the ball is weighed to determine the excess of its proposed weight when finished.

The holes are then machine bored at the respective points, sufficiently deep to reduce the weight to exact specifications.

How are Artificial Precious Stones Made?

The art of manufacturing gems synthetically, that is, by the combination of chemical elements present in the real stone, has reached a high degree of success.

The diamond, which is an allotropic form of carbon, has. .h.i.therto resisted attempts to reproduce it of sufficient size to have a commercial value. By dissolving carbon in molten iron and suddenly cooling the molten ma.s.s by a stream of water, whereupon the outer part contracts with great force and compresses the interior so that the carbon separates out, Moissan, the French chemist, succeeded in isolating small crystals, none, however, as large as one-twenty-fifth of an inch in diameter.

Experiments in the manufacture of the ruby have met with such success that the synthetic ruby is produced of a size and of a perfection that would place a prohibitive value on the natural stone. The ruby, chemically considered, is crystallized alumina, or oxide of aluminum, with a small percentage of oxide of chromium.

Sapphire is of the same material, differing from the ruby only in color.

The ruby owes its fine red color to the presence of oxide of chromium; the sapphire its deep blue to either a lower oxide of chromium or to an oxide of t.i.tanium.

Crystallized alumina in the different colors receives different trade names, as Oriental emerald for the green; Oriental topaz for the yellow; Oriental amethyst for the purple; while the water-clear, colorless crystal is known as white sapphire.

The process of manufacture of rubies is carried on with the oxyhydrogen blow-pipe, to whose intense heat the powdered alumina with its coloring oxides is subjected. Rubies have been thus produced weighing twelve to fifteen carats when cut. The average weight of the native Burmese ruby is about one-eighth of a carat. The sapphire and the so-called Oriental stones are prepared in the same manner, with the addition of proper coloring matter.

The emerald and opal have not emerged from the experimental stage, although Becquerel, a French chemist, is reported to have produced opals from solutions of silicates with high-tension electric currents.

To be distinguished from synthetic gems are reconstructed stones, which (as yet only done with the ruby) are pieces of the natural stone fused together. They are very brittle.

The pearl is not produced synthetically, but many imitations exist. The j.a.panese produce them by fastening a piece of mother-of-pearl in the sh.e.l.ls of the pearl-oyster and allowing it to remain there for a number of years.

The turquoise, a phosphate of aluminum colored with copper, is not synthetically produced, although various experiments with its manufacture have been made.

[Ill.u.s.tration: _Reproduced by permission of The Philadelphia Museum._

MAZZANTINI BULL-FIGHT

The last act in a bull fight, City of Mexico. The bull, tired out by the attacks of the _picadores_ or pikemen, and _banderilleros_ or dart men, whose _banderillas_ or darts are seen planted in the bull's shoulders, faces the _matador_, armed with the _estoque_ or sword, and carrying the _muleta_ or red flag in his left hand, and about to deliver the death stroke.]

What is a Mexican Bull-Fight Like?

Bull-fights are among the favorite diversions of the Spaniards. They are usually held in an amphitheater having circular seats rising one above another, and are attended by vast crowds who eagerly pay for admission.