The boat jumped ahead, but although the two submarines were on courses converging to the harbour mouth, she showed no signs of gaining on the wily ‘159.’

Raymond frowned. Then he rang the bell again and said,—

‘Ask the chief E.R.A. to speak to me, please.’

Presently Hoskins appeared, accompanied by his eternal dirty face, cheerful grin, and lump of oily waste.

‘Sir?’ he queried.

Raymond didn’t speak. He merely pointed to the offending craft on the starboard beam.

A light of comprehension dawned on the artificer’s face. His grin broadened and he fled below.

Twenty minutes later ‘123’ shot through the harbour-gate a good quarter of a mile ahead of her adversary, and as she passed the piers the captain gave the order ‘harbour stations.’

The coxswain took the helm. It was his prerogative, and entering or leaving port none but he was entrusted with the wheel.

The remainder of the crew who could be spared from below fell in and stood at ease on the superstructure, both forward and abaft the conning-tower, under the orders of Seagrave.