“No, no!” Owen answered to this. “You could have done it all without me. It was simple enough.”
“It is simple enough when you know how, isn’t it?” laughed the Doctor. “Well, Allan, we’ll have to leave you with your prize plates. Mind you wash them carefully. If they are to be used as evidence they shouldn’t have any questionable spots on them anywhere. To be sure a flaw could be distinguished from a genuine light impression, unless it was a discoloration in the emulsion. That’s the reason the negatives themselves are better evidence than the prints from the negatives. The negatives could be tinkered so as to show fire in every window, I suppose. But the negatives themselves would show that this had been done. So many tricks can be done in photography that I don’t suppose that a photograph in itself could even be offered as proof. But it is pretty good corroborative evidence when you have the negative.”
“That is what this would be, isn’t it?” asked Edith, “corroborative evidence?”
“I presume so, if the matter goes so far. They probably can prove by eye-witnesses that the fire started on the east side of the wing, at least I should think so; but the camera will be a first-rate supplementary witness. We can testify that it was absolutely impartial.”
“Good fellow,” murmured Edith, patting the camera as if it were her dog Sandy.
After the Doctor and Edith had gone Owen and Allan stood the three plates in a bucket and placed the bucket under the tap.
“That’s as good a washing-box as any,” Owen said, “when you have only three plates.”
While the water overflowed from the bucket into the sink the three boys sat on some boxes that were stored in the room, and talked of the fire, and the camera, and picture-making, and Owen related some of the things that happened to him.
“The first pictures I ever made,” he said, “were of a railroad train. I took one of the train coming up the track, and one when it was going by. I got them both on the one plate, and it was the worst smash-up you ever saw.”
“I suppose every one makes doubles,” suggested Allan.