White Mason, the local officer, was a personal friend, and hence MacDonald had been notified much more promptly than is usual at Scotland Yard when provincials need their assistance.

It is a very cold scent upon which the Metropolitan expert is generally asked to run.
"DEAR INSPECTOR MACDONALD [said the letter which he read to us]: "Official requisition for your services is in separate envelope.

This is for your private eye.

Wire me what train in the morning you can get for Birlstone, and I will meet it--or have it met if I am too occupied.

This case is a snorter.