OUTLINES OF NATURAL PHILOSOPHY* 



sun, should agree with that from altitudes of the 

 stars, is not easily fixed with perfect precision, but 

 is certainly not so great as 1". The sun's horizon- 

 tal parallax is therefore less than 10". 



If the correction above mentioned could be found 

 with perfect precision, this method of determining 

 the sun's parallax, on account of its simplicity, 

 would be preferable to all others. Though it does 

 not aiford a precise measure, it assigns a limit that 

 may be used till a more exact result can be ob- 

 tained. 



The parallax of the sun being less than 10", his dis- 

 tance must exceed 20626 semidiameters of the 

 earth; and his diameter must be to that of the 

 earth in a greater ratio than that of 15',5 to 10", 

 or of 93 to 1. $75. 



SECT. 



