MATHEMATICAL PAPERS. . 133 
way, to be 8’ 4", which makes the difference between Cam- 
bridge and Penobfcot 9' 15". The difference between. Beverly 
and Providence, by deductions from the obfervations, is 2’ 18", 
which gives 1’ 9” between Cambridge and Providence. 
Obfervations of a lunar eclipfe, March 29,. 1782, made : at the 
~. — Prefident’s houfe in Cambridge... 
The going of my clock was afcertained, for the vin of 
this eclipfe, in the fame manner es for the foregoing one £ 
October 27, 1780. ad | 
Mr. Caleb Gannett obferved the eclipfe with me. "The tele- 
{cope I made ufe of was an. achromatic refractor, with a magni- 
fying power of go. Mr. Gannett made ufe of a reflecting te- 
lefcope, of about the fame magnifying power. We had, upon 
the whole, a pretty favourable time ; though the earth's fha-- 
dow, at the moon, did not appear fo well defined as we could. 
have wifhed.* 
The obfervations follow.. 
Apparent Time. 
. ; By Pref. tiere, By Mr, Gannett. 
Bepsigof deedip, o 2u4 7" au grade 
Shadow touches. Harpalus,. | | 22 51 22 $7* 
Tycho, . 2 9T By 19 
covers. Tycho, 29 16 29 4 
. —— touches. Mare Crifium,. 3428.49 .3 28 10. 
eaves. Mare Crifum, 4 28 36. 4 28 17 
leaves MareTranguilitetis,33 40. 34 7 = 
End of the pu l 4.$139- 4/53 33- 
; jon TA ^ — Obfervations: 
e 
* In obfervations A different lunar- T when the ftate of "th atmiófphéte, . 
as far as the eye could determine, has been the fame, tbe corti fs Ae 
^"*pearca much better defined in one, than in another. 
