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muft be, on allfides, pervaded by thefolar rays, which 
muft render it invifible to our light. It is therefore 
only againft the cufps, and that at the ingrefs and 
egrefs, that this atmol'phere is to be fearched for, with 
very large inftruments, and fufficiently well fixed. 
Prince de Croy. 
N. B. I am inclined to believe, that there is no water 
in the moon, for the two cavities, which penetrated 
within the dilk continued concave to the bottom, 
whereas if there had been there any water, the bottom 
ought to have been convex. The mountains in the 
moon mull be very high and hollow ; and that is the 
reafon of their white circle. If ever Tycho could be 
feen edge ways, it would make a beautiful appearance.. 
XXXII. Obfervation of the Eclipje of the Sun the $th 
of Auguft 1766, near the Courgain at Calais. 
XeadNov.2 7 ,r>EGINNING - 5 h 39 m f 
» 7 66 * 13 End - - - 7 19 13 
The fun did not let in the featill about 14 minutes 
afther the end of the eclipfe; that is, at leaft 10 
minutes later than the almanac makes it to do at 
Paris. His lower limb touched the fea at f 23™ in 
thick vapours, which made me prefer thefetting of 
this lower limb rather than the centre. It is ealy to 
conclude the difference, which fhould refult from the 
different fituations of Paris and Calais. 
No 
