Original Photographs Taken on the Battlefields during the Civil War of the United States — John Stuart Mill — John Shaqi
Original Photographs Taken on the Battlefields during the Civil War of the United States
John Stuart Mill · en
Brady's request was granted and he invested heavily in cameras which
were made specially for the hard usage of warfare. These cameras were
cumbersome and were operated by what is known as the old wet-plate
process, requiring a dark room which was carried with them onto the
battle-fields. The experimental operations under Brady proved so
successful that they attracted the immediate attention of President
Lincoln, General Grant and Allan Pinkerton, known as Major Allen and
chief of the Secret Service. Equipments were hurried to all divisions of
the great army and some of them found their way into the Confederate
ranks.
"THE black art," by which Brady secured these photographs, was as
mystifying as the work of a magician. It required a knowledge of
chemistry and, considering the difficulties, one wonders how Brady had
courage to undertake it on the battle-field. He first immersed eighty
grains of cotton-wool in a mixture of one ounce each of nitric and
sulphuric acids for fifteen seconds, washing them in running water. The
pyroxylin was dissolved in a mixture of equal parts of sulphuric ether
and absolute alcohol. This solution gave him the ordinary collodion to
which he added iodide of potassium and a little potassium bromide. He
then poured the iodized collodion on a clean piece of sheet glass and
allowed two or three minutes for the film to set. The coated plate was
taken into a "dark room," which Brady carried with him, and immersed for
about a minute in a bath of thirty grains of silver nitrate to every
ounce of water. The plate was now sensitive to white light and must be
placed immediately in the camera and exposed and developed within five
minutes to get good results, especially in the South during the summer
months. It was returned to the dark room at once and developed by
pouring over it a mixture of water, one ounce; acetic acid, one dram;
pyrogallic acid, three grains, and "fixed" by soaking in a strong
solution of hyposulphite of soda or cyanide of potassium. This
photograph shows Brady's "dark room" in the Confederate lines southeast
of Atlanta, Georgia, shortly before the battle of July 22, 1864. It is a
fine example of wet-plate photography.
[Illustration]