t iii I 
ADVERTISEMENT. 
T H E Committee appointed by the Royal Society to dire<ft the pub- 
lication of the Philofophical Tranfadions , take this opportunity to 
acquaint the Public, that it fully appears, as well from the council-books 
and journals of the Society, as from repeated declarations, which have 
been made in feveral former Tranfadions , that the printing of them was 
always, from time to time, the Angle ad of the refpedive Secretaries, till 
the Forty-feventh Volume : the Society, as a body, never interefting them- 
felves any further in their publication, than by occafionally recommending 
the revival of them to fome of their Secretaries, when, from the particular 
circumftances of their afFairs, the Tranfadions had happened for any- 
length of time to be intermitted. And this feems principally to have 
been done with a view to fatisfy the Public, that their ufual meetings 
were then continued for the improvement of knowledge, and benefit of 
mankind, the great ends of their firft inftitution by the Royal Charters, 
and which they have ever fince fteadily purfued. 
But the Society being of late years greatly inlarged, and their com- 
munications more numerous, it was thought advifeable, that a Committee 
of their members fliould be appointed to reconfider the papers read be- 
fore them, and feled out of them fuch, as they fhould judge moft pro- 
per for publication in the future Tranfadions ; which was accordingly- 
done upon the 26th of March 1752. And the grounds of their choice 
are, and will continue to be, the importance and Angularity of the fub- 
jecls, or the advantageous manner of treating them ; without pretending 
to anfwer for the certainty of the fafts, or propriety of the reafonings, 
contained in the feveral papers fo publifhed, which rnuft ftill reft on the 
credit or judgment of their refpefrive authors. 
A 2 
If 
