But never a hint which could lead to his detection--never anything personal, not a clue to his age, his business, his appearance, even his abode--nothing but this baffling symbol B.45.
"You have cabled all this home, of course," Hillyard observed to Fairbairn.
"Yes.

They know nothing of the B.45.They are very anxious for any details." "He seems to be a sort of letter-box," said Hillyard, "a centre-point for the gathering in of information." Fairbairn shook his head.
"He is more active than that," he returned, and he pointed to a passage here and there, which bore him out.

It was the first time that Martin Hillyard had come across this symbol, and he was utterly at a loss to conjecture the kind of man the symbol hid.

He might be quite obscure, the tenant of some suburban shop, or, again, quite prominent in the public eye, the owner of a fine house, and generous in charities; he might be of any nationality.

But there he was, somewhere under the oak-trees of England, doing his secret, mean work for the ruin of the country.