[ ■3o8 ] 
We thought it prudent therefore, at one o’clock, to 
take off the micrometer from the refledor, which had 
been ufed with a magnifying power of 95 times j 
and, after adjufting the focus, continued the fame 
power for the reafons mentioned* below, in order to 
obferve the tranfit j and led; the external contad might 
happen dill fooner than the earlied: predided time, it 
was refoived, during the hour from one till two, to 
keep an alternate watch, through the rededor, on that 
halfof the Sun’s limb where, the contad mud; happen ; 
while thofe not thus employed were making all other 
preparations as follows, ‘viz. 
1. That each of us might the better exercife our 
own judgment, without being induenced, or thrown 
into any agitation or furprize by the others ; it was 
agreed to tranfad every thing by dgnals, and that one 
obferver diould not know what the others were do- 
ing. The dtuation of the telefcopes, the rededor be- 
ing within the obfervatory, and the two refradors, 
mounted at fome diftance from each other without 
it, favoured this purpofe. Wherefore, 
2. Two perfons, viz. Mr. Sellers, one of our 
committee, for whom no telefcope could be pro- 
* As the refracting telefcopes gave but a fmall lielJ, and were 
very unmanageable, on account of their length, and the Sun’s 
great altitude, it was thought belt to ufe a fmallcr power and 
laro-er held with the refleCtor, that if the contaCt (hould happen 
at a different part of limb than where it was expeCted, one of us, 
at leaft, might be fure not to mifs it, but give notice to the 
others. It was agreed, however, that if the contaCl happened at 
or very near the part of the limb where we did expeCl it, no fuch 
notice was to be given. It was, although, thought beft to have 
fome difference in the magnifying powers; and the vifion with 
the reflcCfor was fo diflindf and well defined, tliat I am well 
rkafed I ufed no higher power, 
vided, 
