but of immediate observation and measurement. Having ascertained this, his 

 next object was to compute the distance to which our sun would have to be 

 removed in order that it should assume an appearance like that of the dogstar. 

 Although this might at the first view appear a difficult problem, it was by no 

 means so. We know by the principles of optics, that if the sun were removed 

 to twice its present distance it splendor would be four times less ; at three times 

 its present distance it would be nine times less ; at ten times the distance it 

 would be one hundred times less, and so on. 



We have, therefore, a simple arithmetical rule of calculation, by the applica- 

 tion of which we can say in what proportion the brightness of the sun would 

 be reduced by any proposed increase of distance, or what increase of distance 

 would be necessary to produce any proposed diminution of brightness". If this 

 rule be applied to determine how much further the sun should be removed from 

 us than it now is, in order that it should be reduced to the appearance of the 

 dogstar, it will be found that the requisite increase of distance would be in 

 proportion of about 150,000 to 1. If, then, the sun were removed to 150,000 

 times its present distance it would be seen by us as a second dogstar. 



Now it will be apparent, that if we had reason to know that the dogstar is 

 at a distance of 150,000 times greater than that of the sun, it would immedi- 

 ately follow that the dogstar must be a sun equal to our own, because then it 

 would be inferred that the sun, if placed where the dogstar is, would have ex- 

 actly the same splendor and magnitude. 



But if, on the other hand, we had reason to know that the real distance of 

 the dogstar is greater than 150,000 times that of the sun, then it would follow 

 that the dogstar at a greater distance would have the same splendor as the sun 

 at a less distance ; and, consequently, the inevitable inference would be that 

 the dogstar must be larger and more splendid than the sun. 



The discovery of Bessel having led to the conclusion that the distance of 

 the nearest stars is at least 600,000 times greater than that of the sun, it 

 follows that these objects, at that distance, are as large and bright as the sun 

 would be at a distance four times less. This being admitted, it immediately 

 follows that the stars, or at least many of them, must be objects transcendentally 

 greater and brighter than the sun. 



At the time of the observations of Dr. Wollaston it was not supposed that the 

 distances of the stars were as great as they are now known to be ; and Dr. 

 Wollaston, adopting a much less distance than the truth, felt himself warranted 

 in the inference that the dogstar must be a sun equal at least to fourteen of 

 ours. Had he known what-has since been inferred from the observations of Pro- 

 fessor Bessel, how much more stupendous would he not have inferred the stars 

 to be! 



But still, it may be asked, what are those wondrous objects ? Are they plan- 

 ets shining with reflected light ? or are they themselves native fountains of 

 light, like our sun ? It is easy to perceive that no reflected light could be in- 

 tense enough to be visible at distances so enormous ; independent of which, 

 the splendor of the stars as seen through powerful telescopes is such as to sat- 

 isfy us that they must be suns. Sir William Herschel stated that when his 

 great telescope was directed to the region of the heavens through which the 

 star Sirius passed, the appearance exhibited on the approach of that star was 

 like that of the eastern firmament on the approach of sunrise ; and that when the 

 glorious object itself entered the field of view, although it appeared as a mere 

 lucid point, having no sensible magnitude, its light was so overpowering that 

 he was compelled to protect his eye with a colored glass. It is needless to 

 say that such splendor could not proceed from an opaque globe shining with 

 borrowed light at a distance of sixty millions of millions of miles. 



