by Jules Verne
CHAPTER XXIV.
THE TELESCOPE OF THE ROCKY MOUNTAINS.
On the 20th October in the preceding year, after the close of thesubscription, the president of the Gun Club had credited the Observatoryof Cambridge with the necessary sums for the construction of a giganticoptical instrument. This instrument was designed for the purpose ofrendering visible on the surface of the moon any object exceeding ninefeet in diameter.
At the period when the Gun Club essayed their great experiment, suchinstruments had reached a high degree of perfection, and produced somemagnificent results. Two telescopes in particular, at this time, werepossessed of remarkable power and of gigantic dimensions. The first,constructed by Herschel, was thirty-six feet in length, and had anobject-glass of four feet six inches; it possessed a magnifying powerof 6000. The second was raised in Ireland, in Parsonstown Park, andbelongs to Lord Rosse. The length of this tube is forty-eight feet, andthe diameter of its object-glass six feet; it magnifies 6400 times, andrequired an immense erection of brickwork and masonry for the purpose ofworking it, its weight being twelve tons and a half.
Still, despite these colossal dimensions, the actual enlargementsscarcely exceeded 6000 times in round numbers; consequently, the moonwas brought within no nearer an apparent distance than thirty-nine miles;and objects of less than sixty feet in diameter, unless they were of veryconsiderable length, were still imperceptible.
In the present case, dealing with a projectile nine feet in diameterand fifteen feet long, it became necessary to bring the moon within anapparent distance of five miles at most; and for that purpose to establisha magnifying power of 48,000 times.
Such was the question proposed to the Observatory of Cambridge. Therewas no lack of funds; the difficulty was purely one of construction.
After considerable discussion as to the best form and principle ofthe proposed instrument the work was finally commenced. According tothe calculations of the Observatory of Cambridge, the tube of the newreflector would require to be 280 feet in length, and the object-glasssixteen feet in diameter. Colossal as these dimensions may appear, theywere diminutive in comparison with the 10,000 foot telescope proposed bythe astronomer Hooke only a few years ago!
Regarding the choice of locality, that matter was promptly determined.The object was to select some lofty mountain, and there are not many ofthese in the United States. In fact there are but two chains of moderateelevation, between which runs the magnificent Mississippi, the "king ofrivers," as these Republican Yankees delight to call it.
Eastwards rise the Apalachians, the very highest point of which, in NewHampshire, does not exceed the very moderate altitude of 5600 feet.
On the west, however, rise the Rocky Mountains, that immense range which,commencing at the Straits of Magellan, follows the western coast ofSouthern America under the name of the Andes or the Cordilleras, untilit crosses the Isthmus of Panama, and runs up the whole of North Americato the very borders of the Polar Sea. The highest elevation of this rangestill does not exceed 10,700 feet. With this elevation, nevertheless, theGun Club were compelled to be content, inasmuch as they had determinedthat both telescope and Columbiad should be erected within the limits ofthe Union. All the necessary apparatus was consequently sent on to thesummit of Long's Peak, in the territory of Missouri.
Illustration: THE TELESCOPE OF THE ROCKY MOUNTAINS.
Neither pen nor language can describe the difficulties of all kindswhich the American engineers had to surmount, or the prodigies of daringand skill which they accomplished. They had to raise enormous stones,massive pieces of wrought iron, heavy corner-clamps and huge portionsof cylinder, with an object-glass weighing nearly 30,000 lbs., abovethe line of perpetual snow for more than 10,000 feet in height, aftercrossing desert prairies, impenetrable forests, fearful rapids, farfrom all centres of population, and in the midst of savage regions, inwhich every detail of life becomes an almost insoluble problem. And yet,notwithstanding these innumerable obstacles, American genius triumphed.In less than a year after the commencement of the works, towards the closeof September, the gigantic reflector rose into the air to a height of280 feet. It was raised by means of an enormous iron crane; an ingeniousmechanism allowed it to be easily worked towards all the points of theheavens, and to follow the stars from the one horizon to the other duringtheir journey through the heavens.
It had cost 400,000 dollars. The first time it was directed towards themoon the observers evinced both curiosity and anxiety. What were theyabout to discover in the field of this telescope which magnified objects48,000 times? Would they perceive peoples, herds of lunar animals,towns, lakes, seas? No! there was nothing which science had not alreadydiscovered! and on all the points of its disc the volcanic nature of themoon became determinable with the utmost precision.
But the telescope of the Rocky Mountains, before doing its duty to the GunClub, rendered immense services to astronomy. Thanks to its penetrativepower, the depths of the heavens were sounded to the utmost extent; theapparent diameter of a great number of stars was accurately measured; andMr. Clark, of the Cambridge staff, resolved the Crab nebula in Taurus,which the reflector of Lord Rosse had never been able to decompose.
