[ 32 ] 
2. The title of this paper renders it almoft need- 
lefs to remind the reader, that the moon’s parallax 
is not here propofed as the proper eft medium for 
determining that of the fun. Our data are ftill too 
uncertain for that purpofe, icarce one of them having 
been determined to an unexceptionable precilion ; 
and the numbers in the table (hew how much a 
fmall difference in the moon’s diftance muft aftedt 
the feveral conclulions. It may be of ufe, how- 
ever, to know in what manner thofe conclufions, as 
well as the quantities from which they derive *, 
ftand related to one another. For if, hereafter, the 
neceffary data ftiould be more exadlly known, the 
calculus may be repeated ; and if the tranfit of 
Venus, which is to happen in 1769, lliould confirm 
Mr. Short’s calculations from that of 1759, we may 
thence conclude the true mean diftance of the moon, 
better than in any other way. 
3. In die mean time, if any perfon fhould have 
the curiofity to examine the numbers of the table, 
he will pleafe to take notice : 
That, as no two meafurements, nor any two 
lengths of a fecond-pendulum hitherto obfervcd, 
make the earth of the fame fpheroid figure, I have 
retained for the ratio of its greateft and leaft diame- 
ters, that of 231 to 230 ; anfwering to the hypo- 
thefis of its uniform denfity : and have thence made 
a degree of the equator equal to 57200 French 
toifes “f*. 
* The connexions of F, Q, are manifefl: ; and the rela- 
tion of M to Q 5 is eafily deduced from Prop. 59. Princip. 
Rook I. 
f This was computed upon the fuppofition, that a degree of the 
meridian at lat. 49°- is 57183 toifes : but if that degree is, by 
The 
