37 6 
TRAVELS 
“ Stockholm, to examine the local fituation and contiguous 
“ grounds, where the French academicians, in the year 1/36, de- 
“ termined the length of an arch of the meridian, as it croffes 
“ the polar circle; with general refledions on the figure of the 
“ earth, and upon the neceffity of new meafurements to afeertain 
“ exadly the equation ; read at a public meeting of the Laid 
“ academy, on the 23 d of Odober, 1799, by Sons Swamberg.” 
“ The aftronomer, as well as the mathematician, are perfedly 
“ agreed, that the fpherical form of the earth’s figure, contains 
“ elements that muff be taken into account, if we would know 
“ from theory the precife quantity of the proceffion of the equi- 
“ noxes and the nutation of the earth’s axis. Thefe equations, 
“ and others * in effed lefs confiderable, but which in the courfe 
“ of ages will be gradually developed, and will at lafl become of 
“ too much importance to be negleded, joined to the influence 
“ which a knowledge more or lefs perfed of the dimenfions of 
“ our planet has on the accuracy of a calculation of all the phe- 
“ nomena which are in any degree concerned in the effeds of the 
“ parallax, have determined the learned for almofl a century and 
“ an half, to make it one of the principal objeds of their mod pro- 
* In order to fatisfy ourfelves of the exiftence of fuch equations, we have only 
to recolleft, that the earth not being a perfect fphere, and that the attraction of a 
body, whatever be its figure, being the fum of the combined attractions of 
all its particles, it neceflarily follows, that the force by which we are drawn to¬ 
wards the fun will not vary exactly in the ratio of the fquare of the diftances, 
and that confequently there will be a very flow motion in the line of the apfides, 
which however infenfible it may be in the fpace of fome decades of years, is not 
on that account the lefs real. 
“ found 
