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flacculent to sound.
Acoustic clouds, in fact, are incessantly floating or flying through the air. They have nothing whatever to do with ordinary clouds, fog or haze; and the most transparent atmosphere may be filled with them, converting days of extraordinary optical transparency into days of extraordinary acoustic opacity."
If such irregularities obtain on perfectly clear days, they are obviously existent to as great, or even greater, extent in fog, when obstruction of vision adds its perplexities to the mariner groping his way like a blindfolded man.
When a ship is proceeding in fog, she has nothing but sound to warn her of her proximity to danger, in the shape of either another vessel or the shore. Hitherto,
human ingenuity has been taxed in vain to improve upon the signals transmitted through air by means of bells, whistles, trumpets and the like. These, being all subject to the aberrations already de scribed, are so unreliable that instead of averting disaster, they have actually at times precipitated it, the hearer being often misled not only as to the distance, but as to the bearing of the sound.
In the wireless telegraph and the submarine telephone, Professor McAdie has found the solution of the great problem.
The wireless telegraph transmits its electric waves instantaneously, regardless of the "acoustic clouds." The submarine telephone transmits sound through water with reliability as to both distance and
direction that for all practical purposes approaches certainty.
He proposes that vessels and shore stations be equipped with both wireless telegraph and submarine telephone plants. During fog, these stations would simultaneously emit a signal. The electric waves from the wireless telegraph travel with the velocity of light, that is, 188,000 miles a second. The wireless signal would therefore be heard the moment it was sent.
The sound waves from the submarine telephone travel at the rate of 4,708 feet a second through water at the normal temperature of 10 degrees Centigrade. They would therefore be heard later than the wireless signal. The elapsed time would be the measure of the distance.
To illustrate, suppose the officer on the bridge of a ship traveling through fog hears the "click" of the conventional wireless signal. Instantly he notes the time and awaits the signal from the telephone, the receiver of which he has at his ear. When he hears this, he again notes the time. The elapsed time in seconds,
multiplied by 4,708, gives the distance of the station in feet, as both signals were despatched at the same time.
For example, suppose that three seconds elapse between the receipt of the wireless and the submarine signals. Three times 4,708 is 14,124 feet. As there are 6,080 feet in a nautical mile this would indicate that the source of the signals, whether another ship or a shore station, is about two and one-third miles away.
No time need be lost by the listener in making computations, as he would have at hand tables showing the distance corresponding to any elapsed time in seconds.
The times may be noted on watch, clock, chronometer or chronograph.
The great advantage of water over air as a medium of sound transmission is in its uniformity. Being homogeneous, with inappreciable variations in density, it transmits the sound waves with reliability.
At the present time, wireless telegraph outfits are provided to ocean going vessels in constantly increasing numbers, and there are numerous wireless telegraph stations along the coasts of nearly every civ
ilized country. Submarine telephone plants are installed upon 38 lightships off the Atlantic and Pacific Coasts of the United States, those in the Pacific being Umatilla reef, San Francisco, Francisco, Blunt's reef. Relief Ship No. 76, and Columbia River. Eight lightships on the Great Lakes are so provided.
Professor McAdie proposes that wireless telegraph and submarine telephone outfits be placed in conjunction at every point where fog signals are now established, especially at dangerous headlands and at the entrance of harbors. He recommends providing vessels with the same. It is a lamentable fact that at the present writing not a single vessel in the Pacific is
equipped with a submarine telephone, although they are common in vessels sailing other seas.
While the submarine telephone and wireless telegraph combined give a ship's distance and bearing from the station, her position may be accurately plotted on a chart if signals are heard simultaneously from two stations, by describing arcs from each station with radii equal to the distance from each. The intersection of these arcs is the ship's exact position.
Thousands of lives and millions of dollars worth of property are imperiled annually by fog at sea. A reliable system of protection is what the maritime community has been seeking for generations.
THE LAST STAND
BY AGNES LOUISE PROVOST
basked in the late afternoon sunshine;
lower Fallsburg baked in it. Upper Fallsburg grew hourly more quiet with the calm of pleasant leisure at the week's end; lower Fallsburg was already beginning to swarm with the Saturday night crowd. Street corners were grouped with idle men and boys from the mills, and buggies and carryalls were bringing their quota from the outlying districts.
Sheriff Tom Rawlins, taking a cut through lower Fallsburg with Bergen, his new deputy, volunteered the opinion that a universal "pay-day" is a pernicious institution.
"By sun-down fifty per cent of this crowd will be doing their best to get drunk and showing up their dispositions. If I had the running of this earth, I'd cut Saturday night out of the schedule. It's a bad thing for too many men to have their pockets full of money at the same. time, and when you add all day Sunday to sober up in, it's a pretty good receipt for trouble."
He dropped his voice slightly as he passed an idling group of men. One of them called to him familiarly. His name was Farley, and he was a yard foreman in one of the mills.
"Evenin', Sheriff. How is it the county ain't givin' Mr. Hansee a pink tea today? He's leavin' us for the penitentiary, ain't he?"
"He's left," said the sheriff briefly, for Hansee was a tender spot with him. The men turned into a corner saloon. Rawlins went on with his deputy, but not too soon to hear an unpleasant laugh as the door swung in.
"In my part of the country," the voice boasted to Farley, "when one man murders
We don't let him
another we hang him.
The Sheriff's brows flickered in a momentary frown. Farley's satellite had described the situation with unpleasant accuracy. The reigning party in Sinclair County had been in power for seven good years of fatness, and the wheels of government were getting clogged. Hansee, an offensive politician of the lower sort, had shot another man in a quarrel, and after a dragging trial had been sentenced to an absurd two years in the State Prison, and a fine which his friends had paid for him. The opposition papers had made much capital out of the lightness of the sentence, and the fact that it was not the first of its kind did not make it sound any prettier.
As they came to the railroad tracks, Sheriff Rawlins turned and looked back at the narrow streets with their lounging men and boys, and the yellow glow of late sunshine on them. He knew the possibilities for mischief that lay there. The track was the social divider of Fallsburg. North of it lay upper Fallsburg, with its prosperous business streets, its white court house and jail giving on the public square, and its decorous residential section, with a century or so of history back of each substantial home. South of the track lay lower Fallsburg, clustering around the mills and the railroad. The "black belt" was there, a straggling section along the river, and in the heart of it lay a human cess-pool where the refuse of both races sent up the reek of its uncleanness to heaven. "Hell's Kitchen," they called it, a nest which generated vice and bred putridity, and filled each night with hideousness. Social Fallsburg was too far off to hear it. Official Fallsburg was dull of hearing, for the Kitchen polled several hundred purchasable votes, and could be colonized for as many more. The prevailing color of the Kitchen was black, but some white men-of a kind-foregathered
in its numerous saloons because they were wider open than others, and now and then white women of the same kind-disappeared in its depths and came out worse than before.
"I'd like to clean out that hole," Sheriff Rawlins said meditatively. "One good job like that and I'd go out of office satisfiedprovided they wouldn't have me back. Howdy, Uncle Joe! Seems to me you look younger than usual."
"Uncle" Joe Babcock stopped at the corner and snickered in senile appreciation. He was an old man, but he could earn a man's wages yet, and was enormously proud of it.
"Howdy, Sheriff! Younger? I've jest been paid off. Ain't that enough to make a man look young?"
He wagged his head and chuckled contentedly as he trudged along. He loved that week's pay.
Just around the corner a loosely built negro was leaning idly, and his stupid face lightened into furtive interest at the sound of voices. He was shiftless and lazy, but he wanted money. It was Saturday night; he must have whisky; his fingers itched for the touch of dice. Uncle Joe Babcock had just been paid off. No formulated plan of action yet stirred the sluggish mind, but he wanted the things that Uncle Joe's money could buy, and a little greedy flame flickered up in his eyes as he listened.
The negro watched the Sheriff and his deputy go their way. Then he moved out and slouched indifferently up the street, keeping his eye on Uncle Joe Babcock, half a block ahead. The old man was in a hurry. Because it was nearer, he frequently went home by way of the Kitchen, and-in daylight-took a short cut through one of its twisting alleys. He was not afraid.
The law found Jim Turford before he had left the Kitchen's dark limits, and rushed him to the county jail for safekeeping. The story of it leaped from mouth to mouth, and lost no detail as it went. Uncle Joe Babcock had been murdered, and a "nigger" had done it.
For several hours Fallsburg thought it over, and meanwhile the saloon doors swung frequently. Sheriff Rawlins' prophecy had already come true.
Night crept in and darkened the shaded. streets, lights blinked here and there, and curious, loud-voiced groups gathered in front of the county jail, on the east side of the public square, but only a pale light or two showed that there was any life behind the high-barred windows. Gradually the groups congested there, talking idly, violent but aimless. The fire in them was smouldering, waiting for something to blow it into flame. It came.
Down in the Kitchen the scared blacks lay quiet, but about eleven o'clock a group of white men from the mills started back to lower Fallsburg across the tracks, and a negro, coming drunk and reckless from the Kitchen's limits, reeled against one of them and cursed him obscenely.
Straight from a heavy shoulder the answer crashed into the cursing mouth, and half an hour later a panting, sobered fugitive cowered in one of the darkest alleys of the black belt, listening to the sound of retreating voices, while the men who had pursued him, foiled of their quarry and augmented to a crowd, turned to sate their wrath elsewhere. A "nigger" had murdered Uncle Joe Babcock that very day, and they would drag him out to retribution. The law was weak, but this time they would be the law. Drunk with anger, they turned toward the county jail, and as they marched, men joined them by twos and threes, by dozens pouring out from saloons and stores, and the mob roar surged ahead of them.
Sheriff Rawlins heard them coming. Once before he had heard that inhuman bellow, swelling from a murmur to the maddened roar which can come from men's throats when the lust of blood is on them. Official Fallsburg heard it also, and stirred uneasily, but official Fallsburg lay low. Election was only a few months off, and it would not be good policy to