It was normally a two hours' railway journey to Bigthorpe, a fairly large town in the East Riding of Yorkshire, but owing to various unforeseen delays the clocks were striking four when Peter reached his destination.

Having obtained direction from a porter as to the nearest way to Thorpe Beck Viaduct Peter walked out of the station, and to his surprise ran into the missing Andrew Norton.

"Hullo!" exclaimed the spy, somewhat guardedly, for he had to feel his ground. "I hardly expected to see you here."

"Nor did I," replied Peter extending his hand, which the other grasped with well-assumed cordiality.

"You've heard?"

"I've heard nothing."

"I wired to my housekeeper yesterday," explained the soi-disant Norton. "Had a sort of nervous breakdown—complete loss of memory."

"The Zep. raid, I suppose?" asked Peter sympathetically.

"Yes, yes, precisely—the Zep. raid, confound it!" said the German hurriedly. "I remember the bombs dropping, and I ran, goodness knows where. Must have wandered about all night. Have some recollection of finding myself at a strange railway station. Eventually I arrived at Bigthorpe, not even remembering my name and address until I found my registration card in my pocket. Deuced useful things those cards. However, since I was at Bigthorpe, I thought I would stay there a couple of days or so to restore my shattered nerves. Just back by the 4.38."

"Can you postpone your return for another day?" asked Peter. "I'm returning to-morrow. But perhaps I oughtn't to detain you, although everything's all right at The Croft."