[ 62 ] 
taken into the account j I was vifited by my friend 
William Rivet, Efq; of the Inner Temple, who 
faid he wilhed he had come fooner, hecaufe he could 
have put me upon a much fliorter method of com- 
putation. I defired him to (hew me his method, 
which he did mofl; readily and chearfully. “ It was 
“ only to reduce the odd hours, minutes, feconds, 
“ and thirds, &c. above the integral days of a luna- 
tion, into the decimal parts of a day j which niim- 
be of days and decimal parts, being nine times 
added together, will be equal to the time contained 
in nine mean lunations. And from thele, the 
“ time contained in any other affigned number may 
“ be found, as follows. 
A Table fliewingthe quantity of time 
contained in any given number of 
mean lunations. The mean luna- 
tion being 29 days 12b 44' 3" a'" 
; or 2 q.i;3o<;908<;io 8 days. 
Lun. Days. Decimals of a Day, 
29*530590^5^08 
59.061 18170216 
3 88.59177255324 
4 1 1 8.12236340432 
5 '47-65295425540 
6 I/7-'^3545'o64*^ 
7206.71413595756 
8:236.24472680864 
91265.77531765972 
Explanation. 
For tens of lunations, remove 
the decimal point one place 
forward j for hundreds of lu- 
nations, two places; for thou- 
fands, thiee places ; and fo on, 
as in the aiinexed example ; 
and then the remaining deci- 
mals may be reduced into 
hours, minutes, feconds, Sic. 
by the common method of re- 
ducing decimals to the known 
parts of an integer. 
Example. 
