PROJECTION and FILING of MICROPHOTOGRAPHIC REPRODUCTIONS JAMES A. AUSTIN
AND
HAROLD P. BROWN
The Jensen-Saldbery Laboratories, Inc., Kansas City, Missouri
M
ICROPHOTOGRAPHIC duplications of sci- between two glass plates such as are ordinarily used in entific literature on 35-mm. film have been made making glass slides. These plates are separated by two available to research workers by Science Service, pieces of cardboard 63 mm. wide, 100 mm. long, and 0.2 under the name Bibliofilm Service,' a t a remarkably mm. thick, which are glued, one a t each of the long sides reasonable price. Such duplications may be readily of the slide, so that the mounts are held h l y in place. enlarged to a convenient size by means of an ordinary The two glass slides are held together by tape along the projection lantern. It is advisable to employ a water edge of the cardboard separator. Only one such mount cell or heat-absorbing glass during prolonged projection holder is necessary but i t is sometimes convenient to to avoid curling or warping of the film. There is no have several. Films mounted as described can be stored in an ordidanger of burning the film. Two methods of preparing the film for projection have nary filing cabinet. Plenty of space is available on the been employed. I n the first method, which is particu- card for notation of identifying data such as the title of larly applicable to short strips, the films were cut into the article, jonmal, book, author, etc. Such a set of segments which were mounted individually. In the cards can be fled according to the Dewey System, second method, which is especially suitable for long Library of Congress Classification, or other systems strips, the film strip was kept intact and projected with more suitable to a particular need. the assistance of a film holder as described below. In some instances, especially in the case of long artiMost duplicates of recent literature are less than twenty cles, it is more convenient to project and iile the micropages per article and can be handled conveniently by photographs as a continuous strip. This may be done the first method. by the following method. Two glass slide plates are Bibliofilm Senrice photographs double pages on a sin- held apart by a cardboard separator 0.08 mm. thick, gle exposure. Sufficient space is left to allow the film to 23 mm. wide, and 100 mm. long and the plates taped tobe cut between these exposures, thus yielding separate gether along the long edge. A window 37 mm. wide and two-page units. These units are mounted between the entire length of the slide is thus left open. This two-ply Bristol cardboards, which are 67 mm. wide and window is just large enough to permit the film strip to 100 mm. long with a window 22 mm. wide and 30 mm. be drawn through without binding. This unit is then set long in the center. A good grade of liquid glue is ap- in a wooden frame which is made just large enough to plied over the sprocket holes of the film on the concave occupy the space usually taken by the slide holder of an side. The film is then placed over the window of one of ordinary projection lantern. This frame is provided the cards so that all of the printed matter is visible. It with a slit opening on the short sides to allow introduchas been found convenient to carry out the entire pro- tion of the film and a window 25 mm. wide and 77 mm. cedure on a glass plate dimly lighted from beneath. The long in the center parallel to the long axis, thus allowing iilm is pressed against the card so that excess glue is the clear vision of all printed matter but screening out removed and the film thoroughly flattened. Glue is ap- the sprocket holes of the film. This window allows the plied on all four sides of the film and along the edges of projection of two exposures or four printed pages a t a the card. The second card is put in place so that all time. printed matter on the film is clearly visible and pressed If desired, small removable spindles may be fastened until a firm seal is obtained. The finished mount is al- to the wooden frame employed in the projector to facililowed to dry while pressure is applied to prevent curl- tate the holding and rolling of the films. ing. The mounts are marked to indicate the position The projected microphotographs show white markings in which they should be inserted in the slide holder for on a black background and are therefore best observed projection and they may be projected by inserting them in a darkened room. The projection may be made large enough to be read simultaneously by several persons. 1 DAVIS, W.,Scicncc, 83, 4024 (1936).
-
