1% Biographical Memoirs 



fun, but by two obfervations made at any other period of the 

 day. This method, however, being (till imperfect, Nieuw- 

 land turned his thoughts towards the improvement of it, 

 and in the beginning of the year 1789 wrote a paper on the 

 fubject, which he tranfmitted to M. de Lalande at Paris, 

 from whom it met with great approbation. In the year 

 1792, when Nieuwland refided two months at Gotha with 

 Major von Zach, thefe two learned men often converfed on 

 this method of finding the latitude, and calculated the refult 

 of obfervations which they had made with a fextant and an 

 artificial horizon. The above paper, enlarged by thefe ob- 

 fervations, was inferted by Major von Zach with Nieuw. 

 land's name in the firft Supplement to Bode's Aftronomical 

 Almanack, Berlin, 1793. 



The above, however, was not the only fervice rendered by 

 this learned man to aftronomy. Newton was the firfl philofo- 

 pher who fpoke of the mutual attraction of the heavenly bo- 

 dies,and who explained the laws of this attraction from mathe- 

 matical principles. D'Alembert, Euler, and Clairaut brought 

 Hill nearer to perfection what Newton had not fufficiently 

 illuftrated, and defcribed the motion of the moon, the mu- 

 tual effect which the planets have on each other, the per- 

 turbations that mud thence be produced in their courfes 

 and the periods of their revolutions, and alfo the laws to 

 which thefe perturbations, are fubject. There however ftill 

 remained to be explained fome irregularities in the pheno- 

 mena of the planets, and that flow variation which takes 

 place in the inclination of the ecliptic. De la Place alfo 

 made fome very accurate calculations on this fubject. All 

 thefe great men adopted a truth, which they knew only 

 from obfervations, that the axes of the planets do not ftand 

 perpendicular, but inclined to the plane of their orbits The 

 axis of the earth, for example, makes with the plane of its 

 orbit, that is, with the ecliptic, an angle of almofl fixty-fix 

 degrees and a half, and this inclination alone produces the 

 feaions } whereas, it the axis of the earth flood perpendicular, 



we 



