222 Gen. Roy’s Account of a 
the diviior, in like manner, increafes by unity to the equator, 
where it becomes t 8 t °- parts. With refpedt to the degrees of 
great circles, obliquely fituated to the meridian, they were 
chiefly intended for facilitating the computations of curvature 
and refraction, where, in any particular cafe, it might be- 
come neceflTary to obtain, to great precifion, the relative height 
of a very diftant Ration with regard to that occupied by the 
inftrument : for in fuch cafes, in RriCnefs, the angle which 
the line makes with the meridian fhould be attended to. 
The computations * for the conftruction of this table have 
been, as may eafily be judged, fufficiently laborious; but hav- 
ing once begun, I was induced to go through with them, con- 
ceiving that a table of this fort would be of general utility ; 
and that it might be very long indeed before the refults of 
future operations, yet to be undertaken in different and very 
remote parts of the globe, would furnifh data for any thing 
better. It mud be by the united efforts of enlightened nations, 
confpiring as it were together in promoting the caufe of fci- 
ence, that great objects, fuch as the determination of the 
magnitude and figure of the earth, can ultimately be obtained. 
Each fhould contribute to it, and all have it more or lei's in 
their power, according to their particular fituation, and that 
% 
* Much care has been bellowed in the various computations for the con- 
flru&ion of the two tables appertaining to this Paper. In the laft, which has 
been the mod laborious, the differences feem to go on fo uniformly, it is hoped, 
no error of any confequence will be found. Here it is proper that I fhould 
mention a typical erratum in one of the tables belonging to my Paper on the 
Barometer, publifhed in the LXVII. volume of Tranfa&ions, for 1777. It is in 
Tab. VI. containing obfcrvations on heights near Carnarvon. In the column of 
obferved height of Mercury on Moel Eilio, Auguft 4, 1775, 1 h. 7 m. P. M. 
inftead of 27.7 14 read 27.214. 
portion 
