 287 pages, 12x18 cm, Hard cover
 In French. (second edition 1913)

The part on
balloon and kite is available as Open Library on this
site:



Metrophotographie
Author J. Th. Saconney, published
1913 (first printed in 1909)
This work is certainly much less
known than Les CerfsVolants Militaires. The strange
title is discouraging. Who knows what is the metrophotographie?
In fact, it is just like photogrammetry. At that time, engineers
and mathematicians had a large knowledge of descriptive
geometry and they could do a lot of calculations on distances
and angles.
A great part of the book is used
to explain it. However, there are many things to discover,
especially when it is so well explained, step by step.
Aerial photography is discussed
twice. First in chapter III where it describes aerial photography
from ballons, kites or airplanes. There is, as usual, many
considerations on the interpretation of the image. I was
so surprised to see all the informations that can be found
just by measuring some points on the image. Now, I understand
the meaning of "metrophotographie" which is given
in the first paragraph of the book: " art of taking
measures by the means of photography". In fact,
it is much more than only calculating some distances and
angles.
The second description on aerial
photography is in annex 2: " Suspensions of cameras".
There are some good ideas to take and to apply to modern
cameras and actual kaping techniques. The pros and cons
if different techniques are explained; one of them is the
Saconney suspension (of course).
What surprised me more is the geometrical
approach, even it is normal in this kind of book. It is
my guess that Saconney is not known as he should be in the
photogrammetry world.
