john_amend_all

This takes place in Inspector French and the Cheyne Mystery, originally published in 1926. Inspector French is attempting to decipher a coded map left by a dying German U-boat captain:

"...I am beginning to think it is merely a cipher. Let us test this at all events. Let us write down the names of the towns and see if that gives us anything."
He took a sheet of paper, while Price found No. 1 on the photograph and Cheyne identified its position with that of a town on the atlas map.

"No. 1," said Cheyne, "is Salisbury."
French wrote down "1, Salisbury."
"No. 2," went on Cheyne, "is Immingham."
"2, Immingham," wrote French, as he remarked "Salisbury - Immingham: S - I. That goes all right so far."
The next three towns were Liverpool, Uttoxeter, and Reading, and though none of the men could see where SILUR was heading, it was at least prnounceable.
But when the next three letters were added French gave a mighty shout of victory. No. 6 was Ipswich, No. 7 Andover, and No. 8 Nottingham. IAN added to SILUR made Silurian.
"Silurian!" French cried, striking the table a mighty blow with his clenched fist. "Silurian! That begins to show a light!"

Sadly, it did not transpire that the German captain had had dealings with our reptilian precursors.