Evening star., 1950-11-13
Black and White Film
Can I axe Color Pictures
Doctor Develops Process
Using Shades of Density
By Thomos R. Henry

Taking color pictures with ordinary
black k-and-white film was announced
through the American Association for
the Advancement of Science here today.
Described as fantastic" the develop
nent promises to be one of the most
revolutionary in the history of photog-
raphy.
It is reported by DR.. Robert D. Bens-
ley Of the department of anatomy. Uni
versity of Chicago, who already has pat
ented the process. The discovery in
its preliminary form came almost by
accident in photographing laboratory
specimens.
The secret lies almost entirely in the
technique Of development rather than
the makeup of the plate or film, DR..
Bensley says He describes what seems
a very complicated process, from the
point of view of theory, which would
have little meaning except for pro-
fessional photographer. In actual ap-
plication, however, it is said to be
somewhat simpler and quite inexpensive.
All Colors Register.
BY series of chemical phenomena, it
is brought out, essentially all the colors
Of the solar spectrum with various va
riations of shade can be obtained from
the black-and-white films.
The process would seem to be, at this
stage, quite beyond the reach of anna
teurs and the theory Of what happens
still is quite obscure especially as to
how some colors are produced.
On ordinary film Dr. Bensley has
taken pictures in natural colors not
only of biological specimens but of
landscapes and people. Some of the
results are described as exceptionally
beautiful.
Actually the report, printed in Sci
ence, the official organ is the American
Association, describes the process as dat
ing back more than a century-even be-
fore the beginnings Of photography it
self. But after some experiments the
process was abandoned as something
which never could attain success.
The role of sweets" in tooth decay
Is becoming well established, according
to reports to the Nutrition Foundation.
Experiments conducted under the di-
rection OF DR.. c. A. Elvehelm Of the
University Of Wisconsin demonstrate this
clearly for cotton rats. When the diet
Of these animals included II per cent
OF sugar-the present average human
consumption in the United States-it
produced as many and as severely de-
cayed teeth as did basal diet contain
ing ST per cent of sugar.
Increasing the sugar level to 80 and
40 per cent at the expense of the cereal
and bread intake, however, did not ap-
preciably increase the extent Of decay.
Reducing the sugar to zero and 2 per
xn%1
OF decay by 80 per cent and go per
cent respectively.
Strange Difference Noted.
A curious difference is shown by the
report of Drs. R. F. Sognnaes and j. H.
Shaw Of the Harvard Dental School
from survey Of Northern European
children during and since the war.
Among Norwegian children studied with
great thoroughness during the prewar,
war and postwar periods. the record was
as follows:
In 1899 when there was plenty of sugar
per cent of the children showed no
decayed teeth; in 1914 when sugar was
essentially unobtainable, 20 per cent; in
1948 when sugar was plentiful again,
80 per cent.
In Sweden, where there was no scarcity
Of sugar, there was no change during
this period. From his study DR.. Sogn-
macs concludes: The reduction in carries
does not parallel the period of reduced
sugar consumption. Rather. the younger
children whose teeth developed during
the period Of low sugar intake show a
reduction in the postwar period when
sugar consumption is again high Their
carries experience is closer to that of
ancient and medieval skulls which have
been studied.