"But you were speaking of this man Porlock." "Ah, yes--the so-called Porlock is a link in the chain some little way from its great attachment.

Porlock is not quite a sound link--between ourselves.

He is the only flaw in that chain so far as I have been able to test it." "But no chain is stronger than its weakest link." "Exactly, my dear Watson! Hence the extreme importance of Porlock.

Led on by some rudimentary aspirations towards right, and encouraged by the judicious stimulation of an occasional ten-pound note sent to him by devious methods, he has once or twice given me advance information which has been of value--that highest value which anticipates and prevents rather than avenges crime.

I cannot doubt that, if we had the cipher, we should find that this communication is of the nature that I indicate." Again Holmes flattened out the paper upon his unused plate.