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arifing from heat and cold ; nor could I iind lei- 
•“ fure to apply any contrivance of this fort. It had 
“ been made foine time before, to determine the va- 
nations arifing from thofe caufes. The pendulum- 
“ rod is a flat fleel bar, with a bob weighing about 
“ twelve pounds, and vibrates in a fmall arch. It 
“ goes eight days, beats dead feconds, does not 
“ flop when wound up, and is kept in motion by a 
“ weight of five pounds. 
“ The ill flate of' my health would not permit 
me to fit up at nights, to take equal altitudes 
“ of the flars. I was therefore obliged to content 
“ myfelf with thofe of the Sun only, I had, 
feme time before this, viz. May 12, got a te- 
** lefcope fixed in the meridian, on an axis with 
“ fine fleel points j fo that the hair in its focus 
** could move in no other diredion than along 
the meridian. I fet up two marks, north and 
“ fouth, about 60 rods diflant each, to which it 
can readily be adjufled, in a horizontal pofition, 
“ by a ferew j as it can likewife by another icrew in 
“ a vertical pofition. The two marks were fliifted 
from day to day, until they were found within lefs 
“ than one fecond of time of the true meridian. 
“ May 20, I likewife put wires, inflead of hairs, 
“ in the telefcope of the equal altitude inflrument j 
** and the following are the obfervations taken both 
“ with it, and with the meridian or tranfit telefcope, 
“ in the order wherein they were made ; 
Equal 
