3 62 Dr. Wilson’s Anfwer to the- 
and reproduction of parts of this refpiendent covering ; is left: 
for theory to guefs at. Though, however, many difficulties 
fhould occur in an attempt of this kind, it would certainly 
be unreafonable on that account to call in queftion the third 
dimenfion of the fpots, as previoufly determined by arguments 
which are liable to no fallacy, and which, are unconnected with 
every kind of theoretical reafonihg.. 
Now, in. the Memoire before me, this fort of diftinCtion has. 
efcaped the notice of the author. His optical arguments, indeed, 
as they regard the firft part of my eflay, put on a juft and proper 
claim to be heared, and have now,, as we conceive, been fully 
anfw.eredl But luperadded to thefe are many others, which, 
though they relate very properly to the view I have given in 
part IL and to that alone, yet finally are hummed up along 
with the reft, as not only militating ftrongly againft that parti* 
cular view, but in order to diiprove that the fpots are excava- 
tions in the luminous matter. 
.1 here think it but juftice to that honourable Body of Gen-- 
tlemen who, in the year 1774, compofed the Council of the 
Royal Society, or the Committee of Papers, to mention, that* 
the publication of the fecond part of mine was more owing- 
to their having confented to my requeft, than to their own fen- 
timents in regard to the fitnefs of fo doing. But as I had be- 
Bowed fome pains upon drawing up thefe views, and as care* 
had alfo been taken to diftinguifh between faCt and any thing' 
like to theory, and as the latter was propounded only in the 
form of queries, there appeared to me no harm in letting that* 
fecond part go forth alfo; efpecially as I flattered myfelf, that' 
thereby a greater curiofity would have been excited, and the- 
fubjyCl of, courfe fooner: inquired into by obfervation. 
As 
