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dional Tranfits of the Sun, obferved with the Inftru - 
merit defcribed in the Fhilof Tranfaff. N° 291, which 
fhews the Noon-time to one or two Seconds. This' 
Way fome of my fkilful Friends (particularly Mr. 
Flamfteed ) fufpeded to be fallacious, and not compa- 
rable to taking the Time by Altitudes of the Sun, or 
fix’d Stars. For a Trial therefore, I gave him a Chal- 
lenge, of obferving fome Eclipfes that we agreed on ; 
which when we compared, we found fo nicely to agree, 
as to Ihew to a Second of Time, or very nearly fo, the 
Difference of the Meridian of the Obfervatory , and 
that of Ufminfler. 
But becaufe the Credit of my Obfervations depends 
upon the Stridnefs of the Time, give me Leave to 
compare my Inftrument with a Quadrant. And here 
I will prefume to affirm, that my Inftrument is no 
more liable to Errors than a Quadrant . 1. It is lefs 
fo, in regard of its Structure : For a little Error in the 
Divifion of a Quadrant’s Limb, or in fixing its Sights 
(whether Telefcopick or Plain) fpoils all. But no 
great Curiofity, or Nicenefs is required in my Meridi- 
an-Inftrument, 2. In point of Obfervation, as much 
Care and Exadnefs is neceffary to guard againft Wind, 
and to take a true Altitude by the Quadrant, as is ne- 
celTary to take a true Azimuth by my Inftrument . 
For if we are fare that the Inftrument is exadly in 
the Meridian (the Manner of which is ffiewn in the 
fore-cited TranfaElion) we can be as fure, and that to 
as few Moments of Time, as any the beft Quadrant 
can ffiew it. And although I cannot fay, that every 
Day, or every Week, I examined the Polition of my In- 
ftrument, yet I did it fo often, as to be fatisfied, that 
not 
