He struck a match and held it aloft. It burned with a pale green flame.
"I wouldn't care to do this with hydrogen," he remarked. "Non-inflammability of the gas practically does away with all risk. When you recall the numerous accidents to aircraft in the earlier stages of the war, you will find that in over eighty per cent. they were caused by combustion. Of course I'm referring to disasters other than those caused directly by enemy action. Now, carry on; up you go ... no, hold on," he added, as a bell rang shrilly just above their heads.
"One of the workmen coming down," said Fosterdyke. "Opening a flap at the top of this shaft automatically rings an alarm, otherwise anyone ascending might stand the risk of being kicked on the head by the feet of someone else descending."
"By Jove! I know that chap!" exclaimed Kenyon, after the mechanic had descended the long vertical ladder.
"Yes, it's Flight-sergeant Hayward," added Bramsdean. "He got the D.C.M. for downing two Boche 'planes over Bapaume."
"That's right," agreed the baronet. "Jolly fine mechanic he is, too. Do you happen to know how he came to join the Royal Flying Corps? No; then I'll let you into a secret. It was in '16 that he enlisted. Previous to that he was a conscientious objector, and, I believe, a genuine one at that. What caused him to change his opinions was rather remarkable. Do you remember that Zepp raid over Lancashire? Hayward was driving a motor-lorry that night somewhere up in the hills north of Manchester; a bomb fell in the road some yards behind him and blew the back of his lorry to bits. He came off with a shaking and a changed outlook on life. Next morning he joined up. Yes, Hayward's quite a good sort; he's been invaluable to me."
"Had any trouble from inquisitive outsiders, sir?" asked Kenyon.
"No, none whatever," replied Fosterdyke. "Touch wood. People in the village hereabouts have seen enough aircraft during the war to take the edge off their curiosity. As for our rival competitors, well, if they can pick up a wrinkle or two it will make the contest even more exciting."
"If we succeed there'll be a stir," said Bramsdean.
"Yes," agreed the baronet; "it's the first who scores in these undertakings. See what a fuss was made when the Atlantic was first flown by aeroplanes. If the feat were repeated, not a fraction of public interest would be directed to it. The novelty has gone, as it were. Even interest in the flight to Australia--in itself an epic of courage, skill, and determination--was limited. Sensations of yesterday become mediocrities of to-day. For instance Blériot's flight from France to England: see what an outburst of excitement that caused. Since then thousands of machines have crossed the Channel without exciting comment. Now I think I've shown you everything that is to be seen. How about lunch?"