“Where is it—where is either one?”
“They were stolen, Chief.”
“Yes!—” Chick’s face became suddenly vivid with excitement, “yes!—but—when I made the blue-print, I picked up two pieces of paper and only discovered it after I had exposed the paper under the tracing!”
Hastily he switched off the white lamp, putting on the ruby light.
“I put the other sheet back, because it didn’t show much—but, you all know, there is a way to force up a stronger image—with intensifier chemicals.”
Feverishly Chick searched in the laboratory cupboard.
Garry aided him, while Don got the trays cleaned, and the Chief came in and closed the door.
Half an hour later Mr. McLeod caused the door to be opened to him.
“What’s going on?”
“Look!” Don’s trembling finger indicated a faint, but clearly discernible figure on a sheet of printing paper. The blue-print had been developed as far as it was possible to bring out the figure. Then a greatly under-exposed camera photograph had been made, on sensitive film, and this, by process of development known to Chick and the rest, intensified the lights and shadows which were more “contrasty” because of deliberate under-exposure. The result was a readable print.