[ 9io ] 
LXXXI, Some Confiderations on a late Treatife 
intituled , A new Set of Logarithmic Solar 
Tables, c, intended Jon a more commo- 
dious Method of finding the Latitude at 
Sea , by Two Obfervations of the Sun ; by 
H. Pemberton, M. D. R. S, Lond. et 
R. A. Berol. S \ 
Read i^6°o!‘ Z °’ A S 11 happens not unfrequently at 
L jl fea- for the unfeafonable interven- 
tion of clouds to prevent the ordinary method of de- 
termining the fhip s latitude by the fun’s meridian 
altitude, even when it is of primary confequence, 
that the true latitude fhould be known j a problem 
for remedying this difappointment is Rated in many 
treatifes of navigation, for finding the latitude of a 
place by any two altitudes of the fun, with the inter- 
val of time between them. 
A problem limilar to this is propofed, and lolved 
inflrumentaily upon a globe, by a very early writer, 
Petrus Nonius (iz), namely, to find the latitude by 
two altitudes of the fun, and the angle made by the 
azimuth circles palling through the fun, when the 
altitudes are taken. And fince more commodious 
and accurate inftruments for meafuring time have 
been invented, than were known to this author, the 
<Giher problem has been propofed for the fame pur- 
( a ) In L;br. De Obferv. ReguJ. et Inftru.n. Geometr. lib. ii. 
C> 14* 
pofe, 
