ti 58 Dr. w 1 l son’s Anfwer to -the 
thing prominent above the general furface, this can he fhewn 
' inconfiftent with fome circum fiances we find accidentally men- 
tioned in the cafe of M. de la hire’s fpot: for of this great 
one, it is laid, that when only IT'' diftant from the limb, the 
nucleus was feen as a very narrow line. This was on June 3, 
1 703, -at fix o’clock in the morning. Now, forafmuch as, at 
that time, its alledged elevation mull have been to^ts apparent 
fubtenfe, very nearly, as radius to cofine of that arch of the 
fun’s circumference whole verfed fine was the 8" of difiance 
from limb, it is impoffible that its breadth could have increafed 
fenfibly in its further progrefs towards the limb ; and how 
any obvious black notch could be produced by the elevation 
^contended for in this cafe, is not conceivable. 
I do not imagine, therefore, that the phenomena of notches 
in the diik, fo inconfiderable and dubious as thefe feem to be, 
are by any means a proof of proje&ing nuclei, or that they 
-are not reconcileable to fpots being deprefiions in the fun. A 
-large fhallow excavation, with the Hoping fides or umbra 
darker than common, may, as has been (hewn, be more or 
lefs perceptible at the limb : and what, perhaps, is a further 
confirmation of this, and feems to evince that a concurrence of 
fuch circumftances is neceffary, is, that fometimes even large 
fpots make no indentation. M. cassini, in Mem. Acad. tom. 
X. p. 581. defcribes the great fpot of 1676, whjch he faw at 
its entrance with a telefcope of 35 feet, as an obfcure line 
parallel to the limb, but no where mentions that it made a 
notch in it. 
Though we now and then fee the furrounding umbra darker 
than at other times, yet when fpots are deep, and the umbrae 
but little dufky, it is indeed impoffible that we fhould fee any 
thing of them, even though large, very near the limb : for 
here even the nucleus which lies buried cannot in the lead 
contri- 
