Directly Derek received particulars he wrote off to the Air Ministry, stating his qualifications and requesting to be transferred to the Marine section, R.A.F. Promptly came a reply acknowledging his communication, and requesting him to call at Room Number So-and-so at the palatial hotel in use as the head-quarters of the R.A.F. Without any preliminaries, Derek was subjected to a brief yet searching examination. What did he know about navigation? Could he box a compass, set a course, read a chart, understand the rule of the road and the use of a lead-line? Could he semaphore and Morse? Could he handle a motorboat in a roughish sea? "Very well," concluded his examiner. "Go home, and if you don't hear from me in a week's time, come up again." The week passed slowly, for Derek was now keenly interested in what he hoped was to be his new rôle. A great feature was that he would still be in the R.A.F. He really didn't want to hear within the week, for the chances were that his services might not be required. The uncertainty of the whole performance was exasperating; he couldn't understand why his fate couldn't be decided on the spot. On the morning of the 7th, just as Derek was about to proceed to the railway station to journey to town, a letter came, with the words, "Air Ministry" printed on the envelope. It was brief, and to the point. Lieutenant Derek Daventry was to report for duty at the Marine Training Depot, Sableridge, on the 19th instant. Whether he had to appear in khaki or in the new Air Force blue, whether he was to take his field kit, or whether he was to have furnished quarters were points on which he was left entirely in the dark. "Good enough, though!" he exclaimed. "This sea-service business is some stunt." CHAPTER XVIII The First Day at Sableridge Derek Daventry's arrival at Sableridge Marine Depot could hardly be described as imposing. It might have been picturesque, or at least bizarre. Upon alighting at Fisherton Station he learnt on enquiry that Sableridge was a good six miles by road, lying, as it did, at the entrance to the extensive Fisherton Harbour. He waited for some time at the railway station in the hope that one of the R.A.F. motor-transport vehicles might put in an appearance. Thwarted in that direction, he tried in vain for a taxi or even a "growler". Finally he bargained with a sleepy youth in charge of a very ramshackle wagonette, who, in consideration of a pecuniary largess of ten shillings, condescended to drive the newly-joining officer to Sableridge.