'Of course. It will be a pleasure,' replied the scientist.

The change over was made and Barney drove off round the Headquarters building. As they came out alongside the quadrangle of lawn in front of it, Khune said:

'It will be an hour at least before they have found your pilot and got your aircraft ready. It always is. Would it interest you to spend ten minutes having a look at my laboratory, and seeing the sort of stuff my swine of a brother is so keen to get his hands on?'

'Yes, I'd like to,' Verney replied. 'Although it may be only a jelly to look at, the thought of the way it can propel tons of metal at thousands of miles an hour through the air is fascinating.'

Khune directed Barney to drive the car round to the back of one of the big steel and glass blocks, and at an entrance to it that had above the doorway, in bold lettering, 'a five', they all got out.

As it was a Sunday the door was shut, but Khune pressed a bell-push and after a few minutes it was opened by a portly elderly man, in a dark blue uniform. He gave Khune one look, then his eyes grew round and he exclaimed:

'Lord alive, Sir! Did you have a crash?'

'Crash! What d'you mean?' Khune frowned.

'Why, for the moment I thought you was a ghost. Can't be more than an hour and a half since you left for Scotland.'

'Scotland?'

'Yes, Sir. You came here round half past two. Special order, you said. Needed urgent for our place in the 'Ebrides. I got hold of Tommy Carden and we loaded twenty drums out of the store on to a runabout. He drove you with it out to the airstrip and when he got back he told me you meant to deliver it yourself and had gone off with it in a plane. Leastways, that's what I thought he said.'

Verney, Khune and Barney stared at the man dumbfounded. The same awful thought was in all their minds. Lothar had never intended to keep the appointment on Lone Tree Hill. He had made it only to get Otto out of the Station for the afternoon. He had arrived there in an aeroplane and impersonated his brother. He had not got the formula, but he had done far better. He had made off with twenty drums of the fuel all ready for use.

17.Unhappy return

Verney was quick to realize that unless he intervened at once, Otto might say something that would start all sorts of undesirable rumours running round the Station, so he glanced at his watch and said:

'I really think we ought to postpone our visit to your laboratory, Mr. Khune, until after we have been along to the airstrip. Perhaps we'll have time to see it later.'