194 PICTURING MIRACLES 



ing machine and that is what it really is a color- 

 printing machine. It is about eight feet high, four- 

 teen inches wide and sixty feet long. The matrix 

 print is fed in on top of the sound track strip, picture 

 for picture, and the red dye picked up by the relief 

 part is pressed into the transparent part of the sound 

 track strip. The surplus color is washed off, then the 

 strip is dried in the machine, coming out and being 

 wound up on a reel. 



On the other side of the same machine a duplicate 

 matrix and sound track strip is getting the green 

 color. It goes through the machine, then they are 

 reversed and each get the other color on top of the 

 first one. 



The result is just the same as if half tones in a 

 printing press were printing those two colors on top 

 of each other on a piece of paper. You get all the 

 combinations of red and green but no blues or yel- 

 lows, although a slight yellow is given by later run- 

 ning it through a weak yellow bath. 



These printing and coloring steps are compli- 

 cated. They require the greatest skill and accuracy. 

 Perfect results are obtained only with the utmost 

 care in each step; negative and positive stock should 

 all be perforated on the same machine and perfectly 

 aligned. The subjects pictured must be lit to give 

 sharp contrasts. Blues and yellows will not picture 



