The ferrotype and how to make it - The Grian Press

POSITIVE PHOTOGRAPHY. 15
libraries, the place of greatest convenience and
access.
Photography may be said to date its origin
from the time of Baptista Porta, who invented
the camera obscura in the 16th century. Between
this period and the time of Wedgewood and
Davy, only a few isolated facts bearing u])on the
subject were brought to light at intervals. It
would profit but little to notice these in the order
in which they occurred, but it is nevertheless interesting
to observe in all great discoveries how
small are the beginnings, as will be seen by the
perusal of the following account of AVedgewood^s
discovery. The property possessed by the salts
of silver, when decomposed by the action of light,
was well known to the earlier chemists, and M.
Charles, a well known French physician, exhibited
in his lectures at the Louvre, a paper capable of
taking silhouette figures by the action of solar
light, but he has left no account of his process. Mr.
Wedgewood, therefore, was undoubtedly the first
person who recorded his attempts to use the sun-
beams for Photographic printing. In the year
1802 he published a paper in the Journal of the
Royal Institution, which he described as '' an ac-
" count of a method of copying paintings upon
"glass, and making profiles by the agency of
"light upon nitrate of silver; with observations
" by H. Davy/^ a gentleman afterward better
known as Sir Humphrey Davy. From this pa-
per the earliest we are acquainted with, in which