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mixture is thoroughly stirred for several Ritchey and his corps of assistants. Few hours with a long clay cylinder. When opticians would care to accept such a the liquid mass reaches the correct stage task, but no other man has had such exof fluidity and assumes the proper color perience in similar work as Professor the great oven is opened at the rear and Ritchey, and Mr. Hooker and Professor a two-wheeled truck, with very long Hale have every confidence in his ability handles, is brought close up to it; pro- to complete the lens which is to unveil a jecting arms of the truck engage rings universe, three hundred times .vaster on the crucible and the glowing pot is than that revealed by the most powerful slowly lifted and drawn out over a great modern refractors. New buildings and circular iron mold. Oftentimes this oper- new apparatus must be designed and ation is hindered by the overflow of erected. It will require a year's time to melted glass, which is likely to cement construct the mounting of the telescope, the pot to the oven floor, whence efforts which will be made at the Union Iron to dislodge it frequently result in the Works. Lack of space will prevent a breakage of the brittle crucible. An iron detailed description of the various operaband is placed about the pot, to reinforce tions necessary to make the finished it, and by means of grappling-irons the mirror. The problem is to produce a crucible is tipped until its contents flows concave paraboloid surface, eight feet into the mold; this is a moment of tre- four inches in diameter, shelving to a mendous interest and importance. The depth of one inch at the centre. The inmold is then covered with an iron plate numerable operations necessary to proand removed to the cooling-oven, which duce this result may be roughly grouped is already heated to the proper tempera- under the following five divisions : rough ture. Here it is walled up and left from grinding ; fine grinding ; polishing ; figursix to eight weeks, the temperature be- ing; silvering. Figuring the paraboloid ing gradually decreased until the glass is surface is the most important and difficold. The four and a half ton disk of cult of these operations, as will be realglass will then be removed for rough ized when it is known that 8,000 square grinding and polishing, merely prepara- inches of surface must be covered and tory to an examination for possible de- that when finished there will be no error fects. A few bubbles do not matter, as of form on any part of it larger than twothey have almost no effect, but the exist- millionths of an inch. ence of cracks or veins will mean that the The experience of Professor Ritchey whole process must be repeated. Some- and his assistants, obtained in their work times a glass of only thirty-six inch dia

on the lens of the great sixty-inch remeter has required ten or a dozen melt

Alector, which is to go into commission ings; these difficulties will be multiplied

at the Solar Observatory at once, has rein making the hundred-inch lens. A final

sulted in the introduction of many imtreatment in the furnace-house for an

proved methods and appliances, which nealing will be necessary, when the lens will be heated even more carefully than

will be of great advantage in this larger before and allowed to cool gradually for

undertaking. many weeks. It should then be ready

It is the judgment of trained astronofor shipment to America.

mers that no greater opportunity has ever On the arrival of the lens at the in- been presented in the entire history of strument shops in Pasadena the delicate astronomy than will be afforded by the work of making the finished optical construction of this twentieth century remirror will be undertaken by Prof. G. W. fector.

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Nature Fights the Railroads

By W. G. Fitz-Gerald

'EASELESS battle with latest link in the “Cape-to-Cairo" sys

Nature's forces, the tem. At Mile 133, Tsavo Station, a pair world's railroad build- of lions appeared on the river banks and ers must fight-battles terrorized the coolie workers for two infinite in variety, and months. When twenty-nine of them had with opponents ranging been eaten by these cunning and resolute from elephants in In- brutes, the coolies struck. Both lions

dia to earthquakes in were old, stiff in the limbs, worn of Japan; with drifting grass in the Argen- tooth, unable to pursue the larger antetine ; snow in Canada ; floods in Mexico; lopes which are their real prey. They locusts in Brazil ; sand in Australia ; hos- displayed almost human intelligence in tile savages in Uganda who convert the waylaying men and picking them out rails into spears, and the telegraph lines from the tents. The climax was reached into money and ornaments for their when the lioness trotted up one day and women.

grabbed a man off an open car just as Man-eating lions stopped all work at the train was slowing into Tsavo. After one time on the Uganda Railroad, the that, there was nothing for it but to

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A TREMENDOUS LANDSLIDE ON THE LEOPOLDINA RAILROAD OF BRAZIL.

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SAND AND SNOW SHIELDS ALONG RAILROAD LINE IN THE HIGHLANDS OF SCOTLAND.

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from these pests, which at certain sea- the Buenos Ayres Great Southern will sons are present in such swarms as actu- often spend $250,000 a year in fighting ally to clog the locomotives and stop the them. Its smaller sister, the Cordova and trains. The Government periodically Rosario Line, is often swept by a veritaorganizes a kind of locust “conscription," ble Niagara that roars across its track, practically forcing every able-bodied man and utterly obliterates the road for the to fight the insects as the common ene- time being. mies of every citizen in the Republic. And as to the Transandine Railroad,

Also in the Argentine the railroads and the Buenos Ayres Pacific, these are

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have to contend with whirling clouds of periodically rent and torn by the Mensoft pampas grass. The Buenos Ayres doza River in flood which comes down Great Southern is especially afflicted in from the snows with inconceivable fury. this way, for it runs through vast plains The Buenos Ayres Pacific has one in a dead straight line for hundreds of stretch, "straight' of two hundred and miles. At certain seasons a wind rises, three miles. Its floods are freakish, for picks up veritable clouds of the long dry there are no water courses, nor any apgrass, and deposits it in clinging beds, preciable slope. The rain, therefore, acmany miles long, right over the track. cumulates on the surface, forming in Deep cuttings have been known to be en- places a monstrous shallow lake from five tirely filled up with this grass, and also to ten thousand square miles in extent. with light dust, which is often even more The "wash-out" is a watery enemy of troublesome than the snow of northern a different kind, and much more discountries.

astrous. They are of frequent occurThe companies erect special wire rence on South American, West Indian fences to entrap the "paja volodora,as and other tropical lines, and are comit is called, and a special staff piles the monly due to a rush of water, caused by stuff into colossal mounds and sets it on a river's sudden change of course. fire. The Argentine companies, too These assaults have been known to have terrible floods to contend with; and sweep the permanent way from under the track, leaving it suspended in mid- were displayed ; yet one day down came air, and held together only by the sleep- the irresistible torrent and in a moment ers and fish-plates. A typical company the central span lay on the ravine's rocky displaying great resource in fighting floor, a shapeless and twisted mass of wash-outs and land-slides is the Mexican spidery ironwork. Inis wonderful line Southern, which suffers much in August is carried across the summit of the Andes and September. On one memorable oc by the thin lips of precipices dreadful and casion ninety landslides fell in a single day! And that same day saw forty-five wash-outs on the road, north of Perian Station. Thus the line has to be protected by stone walls against raging rivers that begin to exercise a “scouring” pressure. This is also defeated by sacks of sand, thrown in around bridge-piers and other threatened railroad works. The same company, like its Indian and Japanese colleagues, has to contend with severe earthquakes which in a moment will convert the best-laid road into a tortuous and sinuous brace of metals, which appear as a nightmare in the eyes of the railroad man.

WAY DESTROYED BY FLOOD.

TRACK OF THE BUENOS AYRES GREAT SOUTHERN RailBut there is no better examples of railroad enterprise than the Callao and sheer; under menacing spurs of rock ; Oroya system in Peru. When the en- and over apparently fathomless gorgesgineers and surveyors were mapping out a magnificent monument of human inthis line, temporary ledges had to be genuity, calling for skill and daring of a blasted for them in the sheer faces of very high order. terrible precipices, so that they might set Among troubles out of the ordinary, up their instruments in a rock-cut niche. too, are the sharp cyclones such as blew

Perhaps the most remarkable feature a train completely over at Frontera Staeven on these lines is the Verrugas Via- tion, on the Cordoba and Rosario Line duct, two hundred and fifty-two feet in the Argentine ; the sea-spray that corhigh and five hundred and seventy-three roded and bent the rails on the Barbafeet long. It cost upwards of $170,000, does systems; and the common narcissus and none but runaway sailors, accus- that plagues the scenic mountain railtomed to work at dizzy heights, were em- roads of Switzerland. ployed in its construction. Great in- The greatest affliction a railroad knows, genuity, patience and resourcefulness however, is the winter's snow. In Rus

sia drifting is prevented
by snow-screens, made
of specially selected
shrubs and tall trees, and
in our own country and
in Canada we find snow-
fighting reduced to a
science. Now a da y s
every Western road has
its own force of rotary
snow-plows, with a
large force of snow-
fighters, every one of
them willing and able to
take up the challenge of.

grim Winter. In the Snow Plow WORKING NEAR THE SUMMIT OF Pike's Peak.

old days when the work

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