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Marconi secured better results in all just outside the rim of the excavating probability by this method than he would wheels. The buckets have a top and have obtained had he used a permanent back, but no bottom. They are shaped station. For in the latter event, he somewhat like the bowl of a dragwould not have had the advantage of scraper ; and, in fact, they act very much great altitude which the employment of like a drag scraper in digging, for as the kites offers.

excavating wheel revolves, each excavating bucket cuts off a slice of earth which

fills the bucket. When the excavating Ditcher Displaces Men bucket reaches the end of the arc near

the top of the wheel, the dirt falls out of WITH a small traction ditcher, two the bucket upon a belt conveyor.

men can do the work of fifteen This trench excavator cuts the full laborers working with spades and shov- depth of the trench at one stroke and els, and of 100 men when the large trac- leaves the bottom exactly in the grade tion ditchers are employed.

desired. The operator sights along the The traction ditcher consists of a trac- sight arm at the targets on the flag poles tion engine, on the rear end of which is provided, and operates a hand wheel that mounted an excavating wheel provided raises or lowers the excavating wheel with excavating buckets fastened to its until the sight arm is at the proper level. circumference, as shown in the accom- In this way the operator has perfect conpanying view. This excavating wheel is trol over the depth to which the excavatopen, that is to say, it has no axle, but it ing wheel cuts and he can keep the botrevolves upon anti-friction wheels placed tom of the wheel within a fraction of

an inch of the desired grade.

By the use of this modern machinery three lineal feet of trench can be dug per minute in ordinary earth a depth of three feet, and at this rate, one machine would dig 180 lineal feet per hour, or 1,800 feet per working day of

teni hours.

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and are built diagonally with two wooden skins, with a waterproof skin between them.

This boat operates at a uniform speed of sixteen knots per hour, and has maintained a speed on a number of official trials, sufficient to guarantee the quality and design of the vessel. These

pinnaces are equipped ENGLISH TORPEDO BOAT.

with engines of the Latest addition to British Navy.

highest class of torpedo

boat machinery. The gen produce a gas that necessitates engines operate at a speed of from 530 abandoning closed works, such as a to 600 revolutions per minute. mine or tunnel during the explosion, As noted in the illustration, a protected and the laborers cannot return to work lookout and pilot house is provided in the for a long time thereafter, depend- bow of the pinnace, and the whole boat ing upon the facility for carrying off is well protected so that it can stand the the gas. Potasimite is said to produce heaviest weather. no noxious gas, the only precaution necessary in its use being that the workmen get out of the way of the flying particles of blasted rock.

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Result of Collision THE "HE tremendous weight and momen

tum of large ocean liners when under way, make it necessary that the greatest care be taken in docking these great ships, or great damage is done not only to the boats but to the piers, in case of the slightest collision.

The accompanying illustration shows the severe damage sustained by the Hamburg-American Liner Deutschland due to a collision with pier in Dover Harbor.

High Speed Pinnace A TYPE of high speed naval craft is

shown in the accompanying illustration,-a 56-foot vedette boat constructed for the English navy. A similar pinnace was constructed at the same shipyard at East Cowes, Isle of Wight, for the United States, as a sample boat, and others have been built for various foreign navies. These high speed boats are constructed of mahogany and teak,

STEAMER DEUTSCHLAND.

Electrical Relics Alcohol Torpedo Boat THE illustrations show the beginnings TORPEDO boats of a type new to

of those electrical devices that have naval warfare are soon to be manurevolutionized the mechanical and engi- factured by the International Power neering sciences. From the early dyna- Company. The vessels are to be opermo of Faraday have sprung mammoth ated by alcohol motors. It is said by generators and a multitude of devices to naval constructors that the use of alutilize their energy. This inventor by cohol motors will enable the manufacthis discovery of the law of induced cur- urers to make a torpedo boat of the same rents laid the basis of modern electrical length and the same tonnage as any science. The Wheatstone bridge ren- steam-power boat, with a saving of onedered possible the comparison of elec- half the weight and one-half the draft. trical resistances, and

That saving would be Prof. Daniell's load

of great advantage. In stone has played also

the first place it will a most important part

enormously increase the in scientific progress.

radius of action of the boat. At present, the coal supply will not enable a boat to make a cruise of more than 400 miles without recoaling.

ELECTRICAL RELICS. In center, Prof. Daniell's lodestone with Faraday's induction coil; in the foreground, the original Wheat.

stone bridge; on the sides are two of Prof. Henry's original induction coils.

British Cross the Seas It is asserted that the alcohol motor boats

will be able to make the trans-Atlantic AN N interesting movement in the commercial world is the recent establish- trip very easily. The saving in draft

will permit them to go up shallow rivers ment in the United States of branch factories by British concerns. Within the

and assist, for instance, in forcing a landlast year there have been four of con

ing for marines; and the saving in weight siderable importance; one for the manu

will permit the carriage of a torpedo facture of weighing machines, at South

boat by a battleship. The enactment of

the free alcohol bill by Congress will Milwaukee ; a chemical concern at Niagara Falls; a fancy cotton goods mill at

cause a spurt in the manufacture of alcoSouth Norwalk, Conn., and a button fac

hol motors of all kinds, and will practory at Baltimore.

tically insure the success of the alcohol This move was due to the conviction

motor torpedo boat. The possibilities of of each concern that they would be better

alcohol as a fuel have so recently been able to hold their trade in America by discovered that one would think that the manufacturing the articles on the ground, many uses to whicli it is being put were and thereby saving the freight and tariff experimental, which, however, is not the duties imposed on English goods.

A Safe Toy Cannon Lake Muskoka to its position on the

railroad line. The weight of the span is A COLLEGE professor has, by his in- one hundred and thirty-six tons.

vention of a toy cannon, made the Fourth of July a safer, though, if possible, a noisier, day. His cannon is operated by acetylene gas, touched off by two Alaska's Telegraphs dry batteries. The turning of a key charges the noisemaker with a mixture EXTRAORDINARY results, in conof air and acetylene. The cannon is fired sideration of the conditions, have been by turning another key, and the report achieved by the United States troops of that follows is said to rival the thunders the Department of the Columbia in the of heaven. As recharging by the flowing construction and maintenance of telein of the gas occurs almost instantly, a graph and cable lines in Alaska. The skillful manipulator may fire the cannon submarine cable system begins at Seattle, every 'other second, or thirty times a Washington, extends to Sitka, thence to minute. Absolute safety is guaranteed in Valdez, and on to Seward, on Resurrecits operation. The hand may be held tion Bay, a distance of 1,838 miles. Two over the cannon's mouth with impunity: branches, one from Sitka to Skagway, a The only drawback to the use of the ma- distance of 413 miles, and the other from chine is perhaps its first cost. Five dol- Taldez to Fort Liscum, a distance of four lars is the price asked.

miles, make the total mileage 2,255.

The volume of business transmitted over these vables, especially the trunk

portion from Seattle to Sitka, has become Floating Steel Span so great that steps have been taken to

accomplish its duplexing which will make THE

IE James Bay Railroad Company of the capacity of the cable equivalent to two

Canada desiring to place a steel wires. bridge span in position adopted the The land telegraph system begins at somewhat unusual method of floating it the terminal of the submarine cable at on scows, upon which a superstructure Valdez and extends as far as Fort St. had been built especially for the purpose.

Vichael. From Fort St. Michael across The illustration shows the manner in

Norton Sound a wireless system has which the operation was performed. been installed with terminals at Fort St. Cables were attached and the strange Michael and Safety Harbor, 107 miles load slowly drawn over the waters of apart. From Safety Harbor a land line

FLOATING SINGLE-SPAN BRIDGE TO PLACE.

carries communication to Nome. This

Latest Submarine trunk line, including the wireless, is 1,433 miles long. It affords means of THE photograph shows the latest type cities of Nome, Fairbanks and other over the surface of the water at a high places where the mining industry is of the rate. of speed. The boat here shown is highest importance. Arrangements have designed for use in warfare and was

been perfected by which communication built under the direction of the French beyond these points may be had by tele- Admiralty, for that purpose. The crew, phone systems on the Seward Peninsula. it will be observed, are few in number, The money turned into the treasury, as as the quarters below deck, as can readily the proceeds of commercial messages be seen, must necessarily be very crowdsent over these lines during the past ed, indeed. vear, amounted to $178,779. The value This type of vessel is attracting everof the business transmitted for the sev- growing attention from all nations and eral government departments aggre- each new example is studied with eager gated $104,807. Amounts collected and interest. This latest adjunct of the turned over to commercial companies as French navy is no exception to the gentheir share aggregated $16,364, during eral rule, as she has had her share of the year.