which invests some of the adventures may possibly give rise to some
suspicion of occasional embellishment; on these points, however, we
leave each reader to judge for himself. In relation to the history of
science, this memoir gives some interesting particulars, which disclose
to us much of the interior spirit of the Academy of Sciences, not always
of a kind the most creditable to some of Arago's former contemporaries.

But a far higher interest will be found to belong to those eloquent
memoirs, or éloges of eminent departed men of science, who had attained
the distinction of being members of the Academy.

In these the reader will find a luminous, eminently simple, and popular
account of the discoveries of each of those distinguished individuals,
of a kind constituting in fact a brief history of the particular branch
of science to which he was devoted. And in the selection included in the
present volume, which constitutes but a portion of the entire series, we
have comprised the accounts of men of such varied pursuits as to convey
no inadequate impression of the progress of discovery throughout a
considerable range of the whole field of the physical sciences within
the last half century.

The account given by the author, of the principal discoveries made by
the illustrious subjects of his memoirs, is in general very luminous,
but at the same time presupposes a familiarity with some parts of
science which may not really be possessed by all readers. For the sake
of a considerable class, then, we have taken occasion, wherever the use
of new technical terms or other like circumstances seemed to require it,
to introduce original notes and commentaries, sometimes of considerable
extent, by the aid of which we trust the scientific principles adverted
to in the text will be rendered easily intelligible to the general