Eighteen Kodachrome films in Ready-Mounts 2" x 2" cost $2.2 5, about 14 cents each if there are no failures. Glass-covered black and white slides of the same size may be made for about the same price. Some other types and larger sizes are higher. It is as easy now to use color as black and white, but the slides are not so durable. Heat and concentrated light affect color, especially the yellows, though the dyes are improving in this respect.

A. The Contlmovie.

1. Can fic ust(! w.ith any

pf<)jti"ti>r uith or \».ithout Sound 2 16 mm. SOti-.^OOO fet-t. 35 mm. SOO-.iOOO (cet. 3. iOOO f( < » \t\ mm. runs

for Hilt hour without

rt ptdtion.

Conlimovir Salrs Co . New York

^^^^"TT^

I i. L

^ 5^^

Satco Pholo Product! Lo« Angrlrt Cal

B. The Sanders Screen.

28 X 42 . - 28 X 50

Motiun Picturr Scrcrn fii Arrr»- »oric4 Co . Inc . New York.

C. Britelite - Truvislon Crysta I Beaded Screen.

30 X 40 and other sizes.

GRAPHIC PRESENTATION

"Engineering and Scientific Charts for Lantern Slidet," Prepared by Sulicommittee of Committee on Standards for Graphic Presentation. Sponsored by The American Society of Mechanical Engineers, New York City. 1932.

Designation

Size of Letters

Sample Letters

Approx.

Height,

inches

HI 175

H-2 ABCDE 0.140

H-3 ABCDE

Same Source as A Above.

0.120

B.

Key to Letfering for Lantern Slides.

Valuable slides may be damaged if left on the screen too long. The Lynhoff Laboratories, Rochester, N. Y., makes a heat-reflecting glass, either clear or diffusing, which may be placed between the slide and the light source in the projector. As a further precaution, irreplaceable slides may be copied in full color at no great expense and with satisfactory results. Cardboard Ready-Mount Kodachrome slides are light and thin.