fifteenth century--or in the letters distributed in Germany by the
religious bodies commissioned to collect alms, that bibliographers now
seek to discover the first processes employed by the inventors of
xylography and typography. It is in a forgotten collection of
indifferent plates, published at Venice by Faush Verantio towards the
end of the sixteenth century, that an engineer, who interests himself in
the history of the mechanical arts, might find the first diagrams of
iron suspension-bridges.

Nothing should be neglected; nothing is useless to whoever wishes
thoroughly to study a subject. An astronomer, who desires to study the
motions peculiar to certain stars, requires to consult all the old books
of astronomy, and even of astrology, which appear the most replete with
error. A chemist, a man who is engaged in the industrial arts, may still
consult with profit certain works on alchemy, and even on magic. A
legislator, a jurisconsult, needs sometimes to be acquainted with the
laws, the ordinances, which derive their origin from the most barbarous
ages; but it is particularly for the biographer, for the historian, that
it is necessary to prepare the largest field of inquiry, to amass the
greatest quantity of materials. This is not only true as regards past
times, but we ought to prepare the materials for future students.
Historical facts which appear the least important, the most
insignificant anecdotes, registered in a pamphlet, mentioned in a
placard or in a song, nay be connected at a later period in an
unforeseen manner with events which acquire great importance, or with
men who are distinguished in history by their genius, by their sudden
elevation, or even by their crimes. We are not born celebrated--men
become so; and when we desire to trace the history of those who have
attained it, the inquirer is often obliged to pursue his researches in
their most humble beginnings. Who would have imagined that the obscure
author of a small pamphlet, "Le Souper de Beaucaire," would subsequently
become the Emperor Napoleon? and that to write fully the life of the
execrable Marat, one ought to have the very insignificant essays on
physics that he published before the Revolution? Nothing is too
unimportant for whoever wishes thoroughly to study the literary or
scientific history of a country, or for one who undertakes to trace the
intellectual progress of eminent minds, or to inform himself in detail
of the changes which ha