Here are two examples of a photo-mechanical engraving process as used in
the early 20th century.
Many thanks to Tom Laronga of
Bellingham, Massachusetts, USA, for sending me several plates, including
the two illustrated here.
These plates would have been used for the rotary gravure process:
i.e. attached to a large drum that rotated
and was inked to produce images. This enabled many copies of the photos
to be made quickly and cheaply, either as individual pictures or,
perhaps for a magazine.
The image is reversed, so lettering in the plate appears backwards.
However, I have reversed the image to show the lettering right way round
in the pictures above.
Small dots can be seen on the plates. Looking at them under a magnifying glass, and in
the enlargements of the details below, they can be seen to be very small holes
like pin-pricks, of different sizes, that would retain ink to be
transferred onto the printed image. In the darker areas of the
plates the dots are smaller and, in some cases, futher apart.