no CLASSICS OF MODERN SCIENCE 

 'Geminorum, I perceived one that appeared visibly larger than the 

 rest: being struck with its uncommon magnitude, I compared it to 

 H Germinorum and the small star in the quartile between Auriga 

 and Gemini, and finding it so much larger than either of them, sus- 

 pected it to be a comet. I was then engaged in a series of observa- 

 tions on the parallax of the fixed stars, which I hope soon to have 

 the honour of laying before the R.S., and those observations re- 

 quiring very high powers, I had ready at hand several magnifiers of 

 227, 460, 932, 1536, 2010, &c., all of which I have successfully used 

 on that occasion. The power I had on when I first saw the comet 

 was 22J. From experience I knew that the diameters of the fixed 

 stars are not proportionally magnified with higher powers, as the 

 planets are ; I therefore now put on the powers of 460 and 932, and 

 found the diameter of the comet increased in proportion to the power, 

 as it ought to be, on the supposition of its not being a fixed star, 

 while the diameters of the stars to which I compared it, were not 

 increased in the same ratio. Also, that the comet being magnified 

 much beyond what its light would admit of, appeared hazy and ill- 

 defined with these great powers, while the stars preserved that lustre 

 and distinctness which from many thousand observations I knew 

 they would retain. The sequel has shown that my surmises were well 

 founded, this proving to be the comet we have lately observed. 



II 



ON THE NAME OF THE NEW PLANET 



By the observations of the most eminent astronomers in Europe it 

 appears that the new star, which I had the honour of pointing out to 

 them in March, 1781, is a primary planet of our solar system. A 

 body so nearly related to us by its similar condition and situation, in 

 the unbounded expanse of the starry heavens, must often be the 

 subject of conversation, not only of astronomers, but of every lover 

 of science in general. This consideration, then, makes it necessary to 

 give it a name, by which it may be distinguished from the rest of the 

 planets and fixed stars. In the fabulous ages of ancient times the 

 appellations of Mercury, Venus, Mars, Jupiter, and Saturn, were 

 given to the planets, as being the names of their principal heroes and 



