Blogs and book

I must not forget to mention another lot of coal-tar derivatives in
which some of my readers will take a personal interest. That is the
photographic developers. I am old enough to remember when we used to
develop our plates in ferrous sulfate solution and you never saw nicer
negatives than we got with it. But when pyrogallic acid came in we
switched over to that even though it did stain our fingers and sometimes
our plates. Later came a swarm of new organic reducing agents under
various fancy names, such as metol, hydro (short for hydro-quinone) and
eikongen ("the image-maker"). Every fellow fixed up his own formula and
called his fellow-members of the camera club fools for not adopting it
though he secretly hoped they would not.
Under the double stimulus of patriotism and high prices the American
drug and dyestuff industry developed rapidly. In 1917 about as many
pounds of dyes were manufactured in America as were imported in 1913 and
our _exports_ of American-made dyes exceeded in value our _imports_
before the war.


Pages:
124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148