He had sat for several minutes gazing absently at these two letters when, like a shot, it struck him that the French word for the number, one, was spelled un. Could the key of the cipher be French? He separated and jotted down the next combination of disks
which gave him the numbers 19. The nineteenth letter of the alphabet is s. He wrote it.
The next symbol was
or the figure 9. The ninth letter of the alphabet is i.
The next symbol was
which, translated, gave him 24. The twenty-fourth letter of the alphabet is x.
He now had the letters s-i-x. And no sooner had he written them in order than the word six stared him in the face and he flushed with pure excitement.