The precious bag was now opened and the twenty-three cheques brought out and laid on the bench in a consecutive series in the order of their dates. They were then fixed by tapes⁠—to avoid making pinholes in them⁠—in batches of six to small drawing boards, each batch being so arranged that the signatures were towards the middle. The first board was clamped to the easel, the latter was slid along its guides until the pointer stood at ÷ 2 on the long-focus scale and Thorndyke proceeded to focus the camera with the aid of a little microscope that Polton had made for the purpose. When Mr. Britton and I had inspected the exquisitely sharp image on the focusing-screen through the microscope, Polton introduced the plate and made the first exposure, carrying the dark-slide off to develop the plate while the next batch of cheques was being fixed in position.

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