Of A record if it is to be useful to science, must be continuously
extended, it must be stored, and above all it must be consulted.
Today we make the record conventionally by writing and
photography, followed by printing; but we also record on film,
on wax disks, and on magnetic wires. Even if utterly new
recording procedures do not appear, these present ones are
certainly in the process of modification and extension.

Certainly progress in photography is not going to stop. Faster
material and lenses, more automatic cameras, finer-grained
sensitive compounds to allow an extension of the minicamera
idea, are all imminent. Let us project this trend ahead to a
logical, if not inevitable, outcome. The camera hound of the
future wears on his forehead a lump a little larger than a walnut.
It takes pictures 3 millimeters square, later to be projected or
enlarged, which after all involves only a factor of 10 beyond
present practice. The lens is of universal focus, down to any
distance accommodated by the unaided eye, simply because it
is of short focal length. There is a built-in photocell on the
walnut such as we now have on at least one camera, which
automatically adjusts exposure for a wide range of illumination.
There is film in the walnut for a hundred exposures, and the
spring for operating its shutter and shifting its film is wound
once for all when the film clip is inserted. It produces its result
in full color. It may well be stereoscopic, and record with two
spaced glass eyes, for striking improvements in stereoscopic
technique are just around the corner.

The cord which trips its shutter may reach down a man's sleeve
within easy reach of his fingers. A quick squeeze, and the
picture is taken. On a pair of ordinary glasses is a square of
fine lines near the top of one lens, where it is out of the way of
ordinary vision. When an object appears in that square, it is
lined up for its picture. As the scientist of the future moves
about the laboratory or the field, every time he looks at
something worthy of the record, he trips the shutter and in it
goes, without even an audible click. Is this all fantastic? The
only fantastic thing about it is the idea of making as many
pictures as would result from its use.

Will there be dry photography? It is already here in two forms.
When Brady made his Civil War pictures, the plate had to be
wet at the time of exposure. Now it has to be wet during
development instead. In the future perhaps it need not be
wetted at all. There have long been films impregnated with
diazo dyes which form a picture without development, so that it
is already there as soon as the camera has been operated. An
exposure to ammonia gas destroys the unexposed dye, and the
picture can then be taken out into the light and examined. The
process is now slow, but someone may speed it up, and it has
no grain difficulties such as now keep photographic researchers
busy. Often it would be advantageous to be able to snap the
camera and to look at the picture immediately.

Another process now in use is also slow, and more or less
clumsy. For fifty years impregnated papers have been used
which turn dark at every point where an electrical contact
touches them, by reason of the chemical change thus produced
in an iodine compound included in the paper. They have been
used to make records, for a pointer moving across them can
leave a trail behind. If the electrical potential on the pointer is
varied as it moves, the line becomes light or dark in
accordance with the potential.

This scheme is now used in facsimile transmission. The pointer
draws a set of closely spaced lines across the paper one after
another. As it moves, its potential is varied in accordance with
a varying current received over wires from a distant station,
where these variations are produced by a photocell which is
similarly scanning a picture. At every instant the darkness of the
line being drawn is made equal to the darkness of the point on
the picture being observed by the photocell. Thus, when the
whole picture has been covered, a replica appears at the
receiving end.

A scene itself can be just as well looked over line by line by the
photocell in this way as can a photograph of the scene. This
whole apparatus constitutes a camera, with the added feature,
which can be dispensed with if desired, of making its picture at
a distance. It is slow, and the picture is poor in detail. Still, it
does give another process of dry photography, in which the
picture is finished as soon as it is taken.

It would be a brave man who would predict that such a
process will always remain clumsy, slow, and faulty in detail.
Television equipment today transmits sixteen reasonably good
pictures a second, and it involves only two essential differences
from the process described above. For one, the record is
made by a moving beam of electrons rather than a moving
pointer, for the reason that an electron beam can sweep across
the picture very rapidly indeed. The other difference involves
merely the use of a screen which glows momentarily when the
electrons hit, rather than a chemically treated paper or film
which is permanently altered. This speed is necessary in
television, for motion pictures rather than stills are the object.

Use chemically treated film in place of the glowing screen,
allow the apparatus to transmit one picture only rather than a
succession, and a rapid camera for dry photography results.
The treated film needs to be far faster in action than present
examples, but it probably could be. More serious is the
objection that this scheme would involve putting the film inside
a vacuum chamber, for electron beams behave normally only in
such a rarefied environment. This difficulty could be avoided by
allowing the electron beam to play on one side of a partition,
and by pressing the film against the other side, if this partition
were such as to allow the electrons to go through perpendicular
to its surface, and to prevent them from spreading out
sideways. Such partitions, in crude form, could certainly be
constructed, and they will hardly hold up the general
development.

Like dry photography, microphotography still has a long way
to go. The basic scheme of reducing the size of the record, and
examining it by projection rather than directly, has possibilities
too great to be ignored. The combination of optical projection
and photographic reduction is already producing some results
in microfilm for scholarly purposes, and the potentialities are
highly suggestive. Today, with microfilm, reductions by a linear
factor of 20 can be employed and still produce full clarity when
the material is re-enlarged for examination. The limits are set by
the graininess of the film, the excellence of the optical system,
and the efficiency of the light sources employed. All of these
are rapidly improving.

Assume a linear ratio of 100 for future use. Consider film of the
same thickness as paper, although thinner film will certainly be
usable. Even under these conditions there would be a total
factor of 10,000 between the bulk of the ordinary record on
books, and its microfilm replica. The Encyclopoedia
Britannica could be reduced to the volume of a matchbox. A
library of a million volumes could be compressed into one end
of a desk. If the human race has produced since the invention
of movable type a total record, in the form of magazines,
newspapers, books, tracts, advertising blurbs,
correspondence, having a volume corresponding to a billion
books, the whole affair, assembled and compressed, could be
lugged off in a moving van. Mere compression, of course, is
not enough; one needs not only to make and store a record but
also be able to consult it, and this aspect of the matter comes
later. Even the modern great library is not generally consulted;
it is nibbled at by a few.

Compression is important, however, when it comes to costs.
The material for the microfilm Britannica would cost a nickel,
and it could be mailed anywhere for a cent. What would it cost
to print a million copies? To print a sheet of newspaper, in a
large edition, costs a small fraction of a cent. The entire
material of the Britannica in reduced microfilm form would go
on a sheet eight and one-half by eleven inches. Once it is
available, with the photographic reproduction methods of the
future, duplicates in large quantities could probably be turned
out for a cent apiece beyond the cost of materials. The
preparation of the original copy? That introduces the next
aspect of the subject.

This article was originally published in the July 1945 issue of The Atlantic Monthly.