*. SCO 



GL . " You say, Jupiter is supposed to be twenty- 

 five times larger than llie earth : and in the next page, 

 that his diameter is supposed to be 130,655 miles. 

 If so, is he not 405)6 times larger than the earth T 



Undoubtedly- But I do not undertake to defend ei- 

 ther one supposition or the other. 



llcmark, 1. " You say, p. 148, Even with respect 

 to the distance of the sun, it is wisest to confess our ig- 

 norance, and to acknowledge we have nothing to rest 

 upon here, but mere uncertain conjectures/' 



I did not say this of the distance of the sun in parti- 

 cular. My words, p. 146 are, " With regard to their 

 distance from the earth, (the distance of all the bodies 

 in the solar system) there is such an immense dif- 

 ference in the calculations of astronomers, even with re- 

 spect to the distance of the sun that it is wises? to 

 confess our ignorance," namely, with regard to tkeir dis- 

 tance. 



To prove that we are not ignorant hereof^ you say, 

 " The knowledge of the sun's distance depends on find- 

 ing its parallax, or the angle that the semi-diameter of 

 the earth appears under at the sun, which angle is so very 

 minute, that an error of but a single second, will give 

 the distance very considerably greater or less than the 

 true distance." It will : and therefore I doubt, whether 

 the distance of any heavenly body can ever be known 

 by this means. 



" But Dr. Keil says, we are assured by various me- 

 thods made use of to observe the sun's parallax, that his 

 distance from us is more than twenty-eight millions of 

 miles." He may be assured : but I am not. " He says, 

 farther, two eminent astronomers have since determined 

 the sun's distance to be about seventy-six millions of 

 miles: now if the least distance possible is absolutely 

 determined, how can it be wisest to confess our ig- 

 norance T If it be But I doubt it cannot be deter- 

 mined at all : at least, not by the sun's parallax : " see- 

 ing this is so very minute, that an error of a single se- 



