be subtracted our expense account, consisting of a twenty-five thousand dollar loss on Virginia's company, a twenty thousand loss on Mr. Vandom's, and a payment to Mr. Vandom of one hundred thousand dollars for his Vodkine formula."

"It's too much," objected Vandom. “I don't think Anna and I spent twelve actual working hours on it after you suggested that we invent such a compound."

"That doesn't matter," returned the Captain crisply. "It was an invention, and one of value, and I am bound to hold inventions as separate from the ordinary services of this organization. I figure that a hundred thousand dollars is about all that you could have made out of it, unless you had gone into the business properly equipped and remained in it permanently."

Mrs. Vandom gave a little shriek of dis

"Didn't you enjoy yourself?" interrupted Hobbs. "You're absolutely shameless in charging for fun."

Captain Kidd, shaking a warning forefinger at them both, tapped the knuckles of his other hand on the table for attention.

"Deducting then a total expense account of one hundred and forty-five thousand dollars, leaves us a net gain of one million three hundred and five thousand dollars from the commendable enterprise of involving two suicidal competitors in bankruptcy, so that we could reorganize them for their own benefit. Seven and a half per cent. of this amount is ninety-seven thousand eight hundred and seventy-five dollars, which amount each of the eight of you will find represented on your checks. The balance, amounting to five hundred and twenty-two thousand dollars belongs to papa.'

"Three polite cheers for papa?" proposed Senator Rigby, verifying the figures on his check, and slipping it, neatly folded, into the armpit pocket of his dress-coat.

(The next story in the Captain

"The chair will consider them cheered," acknowledged Captain Joshua, with a bow of thanks. "With the depositing of these checks we close The American Bitters Company enterprise, and turn our wayward fancies elsewhere. The bureau of information will now open the session and decide upon whom next we shall commercially entertain," and this time Captain Joshua Kidd smiled with his nose, and looked like Beelzebub.

Virginia Tyler, tucking her check somewhere in her flufferies, rose hastily.

"I haven't a bit of information to offer, Captain," she assured him earnestly. “I'd like to be excused. I made an engagement before I thought about its interfering with our meeting to-night."

"It's a little late for an engagement, child," protested Mrs. Glendenning, who maintained a highly worried motherly interest in what this closely knit friendly gathering called "the spoiled family beauty."

"I know it!" sparkled Virginia. "It's perfectly audacious! I'm going to a cabaret show!"

"With whom?" demanded Mrs. Glendenning, usurping a right she was frequently impelled to take.

Virginia looked around the group with rising color, then suddenly she giggled. "Hugh Graves," she half whisperingly confessed.

A laugh went up from every one but John Hobbs.

"Virginia, Virginia!" chided Secretary Martha, beaming affectionately on the girl. "You're the only dangerous member of the Captain's loyal company. We're always so afraid that you'll some day fall in love with one of our customers."

"Maybe I will," she threatened, with only the slightest turn of her eyes in the direction of the gloomy Hobbs; “but this is sort of an obligation," and she giggled again. "Mr. Graves was so nice in helping me pick out my yacht, and he really tried. to urge me to take the more expensive one. Good night, all. Cousin Janet's waiting. Come on, John Hobbs, take me to my coupé," and she patted Mrs. Vandom affectionately on the shoulder as she passed behind her.

At the door she turned.

"Oh, I forgot!" she exclaimed. "I didn't turn in my expense account; for one bolt of pink ribbon. Eighty-seven cents!" Kidd series will appear in July.)

FEW weeks ago there tied up at a London dock a vessel of about 5,000 tons burthen,

A

which to any casual observer would have seemed rather an ordinary looking steamship were it not for one striking peculiarity,-namely, the absence of smokestacks. The vessel flew the Danish flag and bore the name Selandia.

In point of truth, the vessel is the largest craft yet completed-in fact, the only large ship ever put in commission-the propulsive power of which is neither wind nor steam. Ships without sails are common enough; but a steamless steamship is obviously something new under the sun.

The Selandia has engines of a new type, the motive power for which is supplied by sprays of oil instead of by steam. The oil spray is not burned in a furnace, but is injected into the cylinder of the engine itself, and, igniting there, expands explosively and drives the piston forward exactly as steam drives it in an engine of the familiar type. The exhaust consists of a practically colorless vapor which escapes through a tube in one of the masts that carry the wireless equipment of the ship. The exhaust from all the engines working at full speed is said to produce less visible vapor than often emerges from the motor of an automobile.

The oil engine which thus threatens the supremacy of the steam engine is the invention of Dr. Rudolf Diesel of Munich. The inventor has met the usual difficulty in bringing his invention to the attention of the commercial world. But the success he has now achieved justifies, in a measure at least, the glowing predictions in which he declared that his invention would make impossible a repetition of England's late disas

ters in the coal strike, when two and a half million men were out of work; when British railways were running on half schedule; when many ships were tied up at their docks for want of coal; and when the entire industrial activity of England was temporarily in check.

Dr. Diesel declares that his engine permanently breaks the monopoly of coal. For he has solved the problem of using liquid fuel for power production in its simplest and most general form. Any of the natural liquid fuels can be used, and what is more, used simply and economically.

The Diesel engine has passed its period of probation during which it has been used successfully in small engines of many types. Now, numerous vessels, some of them even larger than the Selandia, are building. The interest of the British Admiralty has already been referred to. It is said that the German Admiralty is building a cruiser to be equipped with two six-cylinder engines each of 6,000 horse-power. A sister ship to the Selandia is approaching completion at a shipyard on the Clyde, and the East Asiatic Company is reported to have given orders for two similar vessels, and for two cargo vessels, all to be equipped with Diesel engines.

The explanation of the popularity of the new engine is not far to seek. It is founded on efficiency and on cheapness of operation. Tests have been made on large Diesel engines, showing the consumption of only 0.38 pound of fuel per brake horse-power hour. Marine engines actually in use average 0.4 to 0.44 pounds of fuel per brake horse-power hour, running under full load.

Contrast these figures with the 1.46 pounds of coal required to produce the same

result, and it will be clear that the champions of the new engine are not mere visionaries.

It is estimated that the Diesel engine would drive ship as fast and as far with 100 tons of fuel as the best steam engine would with 350 tons of coal. As the liquid fuel may be stored in tanks placed in the double bottom of the ship, there is an obvious saving in space that is of great importance.

The Diesel engines themselves in the Selandia occupy about as much space as the engine equipment alone of the ordinary steam plant; but even in this regard, a further economy of space will be possible. Meantime, the engine room of the new craft is not only guiltless of dust and smoke, but is cool and comfortable.

The engines of the Selandia are in two sets, each having eight cylinders of 20.8 inches by 28.7 inches, giving together 2500 indicated horse-power at 140 revolutions per minute. The general appearance of the engines is that of ordinary reciprocating steam engines.

The operation of the engine may be briefly described thus: The upward stroke of the piston sucks air into the cylinder. The return stroke compresses the air to about 20 atmospheres, and hence heats it to a high degree of temperature. A spray of oil is then injected into the compressed and superheated air. The heat of the compressed air ignites the oil spray spontaneously, so that its combustion is effected without the use of any igniter such as is used with gasoline engines. This obviously simplifies the action of the engine; and the method of operation permits the use of any crude oil.

It will be obvious that the Diesel engine is a modification of other types of oil engines, and not in itself an absolutely new creation. It will be clear also that its operation is the four-cycle stroke familiar as the Otto cycle. Like the gasoline engine, it can be so constructed as to operate on a two-cycle principle.

In these respects the Diesel engine offers no novelties. Its unique feature is the utilization of compressed air, which does away with special apparatus for igniting the oil. The fact that crude oil of any type may be used gives it vast commercial importance. The oil is blown in by air under pressure of something like 1,000 pounds to the inch,

which operates precisely on the principle of the ordinary hand atomizer. The explosive mixture, then, consists of fine particles of oil in a medium of compressed air.

One recalls the explosions of coal dust in mines and the explosions that sometimes occur in mills when the air is saturated with flour dust; and the thought comes to mind that a Diesel engine might be so modified as to use coal dust or flour or starch granules from any source as a substitute for oil, in an emergency. Such a conceivabilityhowever visionary at the moment-suggests a possible solution of the exhaustion-ofcoal problem that has at least the merit of novelty.

Taking New York to Water

THE blasting down of the last rocky bar

rier between two sections of tunnel under the Hudson, completed the most difficult part of one of the most stupendous engineering feats ever undertaken. The two sections of tunnel, which now become a single tunnel, lie 1,100 feet below the surface of the Hudson River. The tunnel is 3,000 feet in length and is bored through solid rock. When completed, it will be lined with concrete and will constitute a gigantic water pipe, every square foot of the surface of which will be subjected to a pressure of more than 46 tons.

The water which will pass through this gigantic subterranean aqueduct will be brought from the Catskill Mountains. It will reach the west shore of the Hudson at a level about 400 feet above the river; there the shaft through which it will flow makes a sheer drop of 1,500 feet to connect with the horizontal tunnel. At the east end, the tunnel connects with another vertical shaft completing the siphon.

The conduit finally leads under Manhattan Island, still at a depth of several hundred feet, to a terminus in Brooklyn, from which pipes will distribute the water to various regions, including Staten Island; the pipes for the latter going under the Narrows.

It was necessary to sink the aqueduct to the great depth beneath the river because of the peculiar geological nature of the gorge through which the Hudson flows. The engineers found that this gorge is filled to a depth of 800 feet with loose glacial drift. It seemed well, therefore, to go below this,

The Selandia, largest oildriven ship afloat, a 5,000 ton Danish vessel equipped with the Diesel engine

Dr. Rudolph Diesel of Munich, who has invented a combustion engine which

in order that the aqueduct might run through solid stone and thus be afforded almost absolute permanency.

But for that matter the principles of engineering involved in the construction of aqueducts have been well known for more than two thousand years. It has been suggested that even such a feat as tunneling under the Hudson

at a depth of a quarter of a mile probably did not lie beyond the skill of the Roman engineers. To be sure, no precisely

makes a pound of crude oil do the work of three and a half pounds of steam coal

comparable task was ever undertaken in antiquity. But the Romans carried the art of tunneling mountains to a high de

gree of perfection, as illustrated, for example, in the cutting of a tunnel three miles long through the Monte Affliano in the time of the Emperor Domitian to shorten the Aqua Claudia. The chief Roman aqueducts were subterranean throughout a large part of their

Even the Greeks, who fell far short of the Romans in engineering skill, on occasion tunneled mountains in bringing water to their cities, as in the well