In the year 1849, the judge of the Criminal Court of the Seine, begged me to examine a hundred and fifty packs of cards, which were supposed to have been tampered with.
They were found in the possession of a man, whose antecedents were far from being as pure, as the colour of his cards.
The cards were in fact all white, and had hitherto defied the most minute inspection.
It was impossible for the most practised eye to discover, that they had been altered or marked in any way.
They seemed all of the best quality.
I spent nearly a fortnight in examining (not only with my naked eye, but with a strong magnifying glass) the card board, the shape, and the almost imperceptible shades, of each of these one hundred and fifty packs of cards.
I could detect nothing; and tired out, I was going to give the same opinion as the experts who had previously examined them.
"There is certainly nothing wrong with these cards," exclaimed I, one evening, in a pettish tone, throwing the pack from me across the table.
All at once, on the shining back of one of the cards, near one of the corners, I thought I saw a dull-looking spot, which had before escaped me. On looking close at it, it disappeared; but strange to say, as I went far off from it, it re-appeared.
"How glad I am," cried I aloud, enthusiastically. "Now I see what it is. It's all right. This then is the mark!" and following the rules, used by sharpers, I satisfied myself, that on every card there was the same spot, which, being placed in various parts, were distinctive signs of the card and the suit. The following was the way the thing was done.