ADVERTISEMENT.

MORE than twenty years have elapsed since the publication of the first volume of the Society's Memoirs. In this period five successive volumes have appeared, the two last of which were published in separate parts. The first and second have been reprinted, and a few of the copies are still on sale; the third is out of print ; and some of the fourth and fifth remain in the publisher's hands.-The progress of the experimental Sciences has been so considerable of late years, as to render ineligible the republication of Essays however valuable originally. The inability, also, of procuring a complete set of the Memoirs has deterred some persons from purchasing the former volumes. These considerations have induced the Society to commence a second series, and they have accordingly denominated this the first volume of the series; it being also the sixth published by the Society since its Institution in 1781.

The Society wish it to be understood, as formerly, that they do not consider themselves answerable for the accuracy of the facts and reasoning in the several Essays: but that the responsibility rests entirely with the respective authors.

November 6, 1805.