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ADVERTISEMENT. 
T H E Committee appointed by the Royal Society to direct 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 Tranf actions, that the printing of them was 
always, from time to time, the fingle aft of the refpeftive Secretaries, till 
the Forty-feventh Volume : the Society, as aBody, 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 inflitution by the Pvoyal 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 advifable, that a Committee 
of their members fhould be appointed to reconfider the papers read be- 
fore them, and felefl out of them fuch as they fhould judge moll pro- 
per for publication in the future Tranfadions ; which was accordingly 
done upon the 26th of March 1752. And the grounds of their cl oice 
are, and will continue to be, the importance and fingularity of the fub- 
jects, or the advantageous manner of treating them ; without pretending 
to anfwer for the certainty of the faffs, or propriety of the reafonings, 
contained in the feveral papers fo publifhed, which mud Hill reft on the 
credit or judgment of their refpeftive authors. 
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