SCENERY OP THE HEAVENS. 



then he may form some idea of the awful gulf between us and the stars, from the 



fact that the triangle formed by lines drawn 

 from the extremes of the orbit to a star at the 

 vertex, has defied the most perfect instruments 

 of human invention to measure, so inappre 

 ciable is it. Supposing the whole of that 

 orbit filled with a globe resplendent as the 

 sun, it would have a circumference of 600 

 millions of miles, and yet have only the appearance of a twinkling atom as seen from the 

 nearest of the stars. 



Previous to the determinations of Newton, the discovery of an annual parallax of the 

 stars was a point of great interest in order to confirm the Copemican doctrine of the 

 earth's motion in space. It was remarked by opponents, that if we are really sweeping at 

 a prodigious rate in an enormous ellipse around the sun, then ought the stars to appear 

 continually displaced, just as do the trees of the forest to the traveller flying swiftly past 

 them, instead of which, seen from any point, and at any time, their position is ever the 

 same fixed, immutable, eternal. Hence the stars were confidently appealed to as bright 

 and unimpeachable witnesses of the falsity and extravagance of the Copernican system. 

 This reasoning was well founded. Only one reply could be made to it, that such was the 

 enormous distance of the sphere of the fixed stars, that no perceptible change was occa 

 sioned by the revolution of the earth in its orbit. More than three centuries have rolled 

 away since the controversy commenced. Though long since terminated by the truth of 

 the grand theory of Copernicus being triumphantly established, yet astronomers have 

 prosecuted with zeal the search after an annual parallax of the stars, in order to illustrate 

 the scale upon which the universe is built ; but no success attended the effort until our 

 time. Bradley failed to detect the slightest indication of it in the instance of y Draconis, 

 elaborately watched; but was unexpectedly led by the attempt to his great discovery of 

 the aberration of light. Herschel, too, was equally unsuccessful in the pursuit of the 

 same object, yet similarly fortunate, as his labours on the occasion were rewarded with the 

 disclosure, that the double stars are not examples of accidental optical proximity, as 

 before supposed, but bodies physically connected, magnificent systems of revolving suns. 



The problem of stellar remoteness has been solved in the present age, in the first 

 instance by the late Professor Bessel, of Konigsberg, and has been justly styled a magni 

 ficent conquest. The world is indebted for it to one of the refracting telescopes of the 

 celebrated Frauenhofer, of Munich, an instrument of extraordinary power, specially 

 adapted to the research for the parallax of the fixed stars. To give some idea of the 

 delicacy of the contrivances with which these great telescopes are provided, Mr Mitchel, of 

 the Cincinnati Observatory, states, that the micrometer of his refractor is capable of 

 dividing an inch into 80,000 equal parts ! When mechanical ingenuity failed to construct 

 lines of mathematical minuteness, the spider lent his aid, and it is with his^ delicate web 

 that these measures are accomplished. Two parallel spiders' webs are adjusted in the 

 focus of the eye-piece of the micrometer, and when the light of a small lamp is thrown 

 upon them, the eye, on looking through the telescope, sees two minute golden wires, 

 straight and beautiful, drawn across the centre of the field of view, and pictured on^ the 

 heavens. The observer has them completely under his control, and can so revolve them 

 as to bring them into any position, increasing or decreasing their distance at pleasure. 

 With machinery even more delicate than this, better adapted to the purpose, and of a 

 somewhat different kind, Bessel renewed the search after the unattained parallax of tL 

 stars. His instrument, called the Jieliometer, was mounted in the year 1829, but various 

 causes delayed his principal operations up to the month of October 1837. 



