Derek heard the tidings without emotion. He remembered his first medical examination for the service; how it filled him with trepidation, as he feared that the doctor would discover some defect hitherto unknown to him. Since that time Daventry had become case-hardened. The examination, which might prove an ordeal to many, hardly troubled him in the least. The R.A.M.C. Captain, an elderly man, whose rugged features and bull voice were merely foils to a kindly and sympathetic nature, wasted no time. "You're O.K., Daventry," he declared, "fit as a fiddle. I'll put you in A category. That means you're all right for aerial work. Why, what's the matter? You don't look pleased." There was an expression of perplexity in Derek's face. A few months previously he would have hailed with delight the prospect of being a knight of the air once more; now a different feeling had arisen. The innate seaman's instinct had developed. He loved the sea; the actual marine work at Sableridge fascinated him. The thought of having to sever his connection with the depot rather staggered him. "It's the uncertainty of everything that's worrying me," remarked the doctor, after Derek had explained. "Here am I, Medical Officer of Health to a large manufacturing district, hanging about here with precious little to do, while there are tons of work awaiting me at home. The authorities can't make up their minds, or if they can they won't, and the consequence is I'm at a loose end. Now, only the other day----" Just then the doctor's flow of oratory was cut short by the arrival of a messenger. "Mr. Daventry here, sir?" he enquired. "The Major wants to see him at once." Hastily donning his tunic Derek made his way to the room of the Second in Command. "Oh, Daventry," began the Major, returning his subordinate's salute. "I've a little stunt for you. There's a wireless message just been received at Baxton and telephoned on to us. A large seaplane has been forced to descend here"--he placed his finger on a large chart of the English Channel--"latitude so and so; longitude so and so. Why she's come down we don't know, but she's wirelessed for assistance. I want you to take R.A.F. 1292 B and make for her at full speed. Get hold of her and take her in tow. I'll send No. 21 to give a hand in case she's too much of a handful. 1292 B has plenty of petrol, I hope?" "Yes, sir," replied Derek. "Filled up this morning." It was one of Daventry's forms of recreation, in the hum-drum days of the demobilization period, to see that boats immediately under his charge were kept as efficient as the scarcity of hands permitted. Every day he had the engines running, so that the boats would be in a state of seaworthiness. No. 1292 B was a twenty-two knotter, while No. 21 was capable of doing only nine and a half knots. Could he get the crippled sea-plane in tow with the first boat he could slow down until the more powerfully-engined No. 21 could relieve her of the tow.