by Jules Verne
CHAPTER XXIV
THE TELESCOPE OF THE ROCKY MOUNTAINS
On the 20th of October in the preceding year, after the close ofthe subscription, the president of the Gun Club had credited theObservatory of Cambridge with the necessary sums for theconstruction of a gigantic optical instrument. This instrumentwas designed for the purpose of rendering visible on the surfaceof the moon any object exceeding nine feet in diameter.
At the period when the Gun Club essayed their great experiment,such instruments had reached a high degree of perfection,and produced some magnificent results. Two telescopes inparticular, at this time, were possessed of remarkable powerand of gigantic dimensions. The first, constructed by Herschel,was thirty-six feet in length, and had an object-glass of fourfeet six inches; it possessed a magnifying power of 6,000.The second was raised in Ireland, in Parsonstown Park, and belongsto Lord Rosse. The length of this tube is forty-eight feet, andthe diameter of its object-glass six feet; it magnifies 6,400times, and required an immense erection of brick work andmasonry for the purpose of working it, its weight being twelveand a half tons.
Still, despite these colossal dimensions, the actualenlargements scarcely exceeded 6,000 times in round numbers;consequently, the moon was brought within no nearer an apparentdistance than thirty-nine miles; and objects of less than sixtyfeet in diameter, unless they were of very considerable length,were still imperceptible.
In the present case, dealing with a projectile nine feet indiameter and fifteen feet long, it became necessary to bring themoon within an apparent distance of five miles at most; and forthat purpose to establish a magnifying power of 48,000 times.
Such was the question proposed to the Observatory of Cambridge,There was no lack of funds; the difficulty was purely oneof construction.
After considerable discussion as to the best form and principleof the proposed instrument the work was finally commenced.According to the calculations of the Observatory of Cambridge,the tube of the new reflector would require to be 280 feet inlength, and the object-glass sixteen feet in diameter.Colossal as these dimensions may appear, they were diminutivein comparison with the 10,000 foot telescope proposed by theastronomer Hooke only a few years ago!
Regarding the choice of locality, that matter waspromptly determined. The object was to select some loftymountain, and there are not many of these in the United States.In fact there are but two chains of moderate elevation, betweenwhich runs the magnificent Mississippi, the "king of rivers"as these Republican Yankees delight to call it.
Eastwards rise the Appalachians, the very highest point ofwhich, in New Hampshire, does not exceed the very moderatealtitude of 5,600 feet.
On the west, however, rise the Rocky Mountains, that immenserange which, commencing at the Straights of Magellan, followsthe western coast of Southern America under the name of theAndes or the Cordilleras, until it crosses the Isthmus ofPanama, and runs up the whole of North America to the veryborders of the Polar Sea. The highest elevation of this rangestill does not exceed 10,700 feet. With this elevation,nevertheless, the Gun Club were compelled to be content,inasmuch as they had determined that both telescope andColumbiad should be erected within the limits of the Union.All the necessary apparatus was consequently sent on to thesummit of Long's Peak, in the territory of Missouri.
Neither pen nor language can describe the difficulties of allkinds which the American engineers had to surmount, of theprodigies of daring and skill which they accomplished. They hadto raise enormous stones, massive pieces of wrought iron, heavycorner-clamps and huge portions of cylinder, with anobject-glass weighing nearly 30,000 pounds, above the line ofperpetual snow for more than 10,000 feet in height, aftercrossing desert prairies, impenetrable forests, fearful rapids,far from all centers of population, and in the midst of savageregions, in which every detail of life becomes an almostinsoluble problem. And yet, notwithstanding these innumerableobstacles, American genius triumphed. In less than a year afterthe commencement of the works, toward the close of September,the gigantic reflector rose into the air to a height of 280 feet.It was raised by means of an enormous iron crane; an ingeniousmechanism allowed it to be easily worked toward all the pointsof the heavens, and to follow the stars from the one horizon tothe other during their journey through the heavens.
It had cost $400,000. The first time it was directed toward themoon the observers evinced both curiosity and anxiety. What werethey about to discover in the field of this telescope whichmagnified objects 48,000 times? Would they perceive peoples,herds of lunar animals, towns, lakes, seas? No! there wasnothing which science had not already discovered! and on all thepoints of its disc the volcanic nature of the moon becamedeterminable with the utmost precision.
But the telescope of the Rocky Mountains, before doing its dutyto the Gun Club, rendered immense services to astronomy. Thanks toits penetrative power, the depths of the heavens were sounded tothe utmost extent; the apparent diameter of a great number of starswas accurately measured; and Mr. Clark, of the Cambridge staff,resolved the Crab nebula in Taurus, which the reflector of LordRosse had never been able to decompose.
