Then Thorndyke and Dr.Norbury rose from their chairs and went towards the mummy, which they lifted tenderly while Polton drew from beneath it what presently turned out to be a huge black-paper envelope.

The single glow-lamp was switched off, leaving the room in total darkness, until there burst out suddenly a bright orange-red light immediately above one of the trays.
We all gathered round to watch, as Polton--the high-priest of these mysteries--drew from the black envelope a colossal sheet of bromide paper, laid it carefully in the tray and proceeded to wet it with a large brush which he had dipped in a pail of water.
"I thought you always used plates for this kind of work," said Dr.
Norbury.
"We do, by preference; but a six-foot plate would be impossible, so I had a special paper made to the size." There is something singularly fascinating in the appearance of a developing photograph; in the gradual, mysterious emergence of the picture from the blank, white surface of plate or paper.

But a skiagraph, or X-ray photograph, has a fascination all its own.

Unlike an ordinary photograph, which yields a picture of things already seen, it gives a presentment of objects hitherto invisible; and hence, when Polton poured the developer on the already wet paper, we all craned over the tray with the keenest curiosity.
The developer was evidently a very slow one.

For fully half a minute no change could be seen in the uniform surface.