92 PHOTO INTERPRETATION PICTURE, COLWELL
3. The importance of photo interpretation as am aid in discovering and evaluating natural
resources is being officially acknowledged at the highest levels.
There are many indications of the truth of this claim, of which only two will be
cited here.
a. The United Nations for the past several years has actively sponsored projects in
which photo interpretation has been the primary tool for making natural resource inven-
tories of under-developed countries. This same organization has also been active for
several] years in disseminating in many languages information on the procedures and
techniques by which such inventories can be made.
b. The President of the United States has recently appointed a special committee to
review that country's foreign aid programs to see if they are adequate to deal with the
problems arising from rapid population increases in certain under-developed parts of
the world. One of the most important of these programs, sponsored by the International
Cooperation Administration, in conjunction with the Pan American Institute of Geo-
graphy and History, involves the preparation of a series of training films, each dealing
with aerial photo interpretation as an aid in the discovery and evaluation of a particular
natural resource (timber, minerals, water, soil, forage). At the time of this writing the
first three films of this series have been completed (in color and sound) and two others
are well underway. The sound track, (narration) for at least one of these films is avail-
able in each of ten languages, and it is anticipated that a similar treatment eventually
will be given to each of the other films in the series.
One indication of the importance of projects such as those just described is to be
found in the information given us by population experts. They tell us that three-fourths
of the world's population growth in the next forty years will be in the under-developed
countries. Unless the people of these countries can be taught how to discover, evaluate
and develop their natural resources at a far more rapid rate than at present, their living
standards will become so unbearably low that millions of them will die of starvation and
exposure. Photo interpretation when properly used is thus seen to have humanitarian
values that heretofore have been largely overlooked.
4. A rational view regarding the merits and limitations of photographic interpretation
keys is gradually emerging.
As a result of various symposia and other discussions on the subject (Roscoe, et al,
1955) (Manual of Photo Interpretation, 1960) there seems to be a much clearer under-
standing than formerly that even the staunchest supporters of photo interpretation keys
do not advocate them as the “cure-all” to every photo interpretation problem. With this
point established, the critics of photo interpretation keys seem more willing to acknow-
ledge that properly constructed keys can often serve a very useful purpose. Objective
tests of the efficacy of keys (De Lancie, et al, 1957) have done much to place discussions
regarding their value well above the plane of mere conjecture.
5. Photo interpretation is invading fields in which it was relatively unknown until
recently.
Only three of these fields will be mentioned here.
a. In mewspaper reporting. At the time of the 1952 World Congress it was indeed
a rarity to find aerial photos used in newspapers as a means of portraying current events.
Now such photos appear almost daily in many of the large newspapers of the world. The
steadily increasing demand for such photos demonstrates that even the average news-
paper reader has the ability to do useful photo interpretation, even when he is obliged
to use the highly degraded aerial photographic images appearing in today’s newsprint.
b. In comparative analysis of sequential photography. Until recently very few non-
