David watched the last of the soldiers disappear around the bend, then glanced at his watch again. Twelve seventeen. Give the fellows another hour. He ran various scenarios through his mind. Could have been caught crossing the border. Might have been seen coming down through the forested slopes on this side. Likely their stories of fleeing French conscription would hold unless a soldier recognised the strange Quebecois accent.

He stared across the lake at the snowy peaks rising above the blue ridges. If they had been apprehended, they would have been held, not turned back. If they were captured, where are they? Why were there twelve soldiers coming out of the trees? Why spread out like that, in groups of two? Was it a routine patrol? Or was it men coming back from helping handle an incident? Too many questions. Need to stop thinking.

The movement at the edge of the trees startled him from his thoughts, and he turned his head to watch two deer bolt from the forest, bound across the road and scamper up the grassy knoll on the other side. So graceful, so spry. When the deer had disappeared from view, he turned his eyes back to the trees and held them out of focus watching for movement.

If the soldiers had been involved in searching for border crossers, or in their apprehension, they would have questioned me. I'd be suspicious to them sitting here at the obvious end of the route. More motion in the trees snapped his eyes into focus, and he saw a man cup the top of his head with an open hand.

David looked up and down the road, then copied the signal as he breathed a loud sigh. He climbed from the cab and opened the lorry's rear doors while motioning for the men to climb in and pointing to the basket of food. "Nous mangerons en route. Les deux supérieurs à l'avant... We'll eat along the way. The two senior in the front."

As David drove up the hill toward the village of Givrans, Sergeant Gerrard Perrier introduced himself and described their adventures. "We were on top of the second ridge, with the lake in sight again, when we saw two soldiers below, Sir. Lucky, we were in a good place to watch them from above. They were moving across the slopes in pairs, probably two dozen of them."

"Twelve came out here and down along the road. Two spoke briefly with me. The others must have come out beyond the bend."

"We figured with the time of day, they were heading to lunch, Sir. So we waited until we saw the first of them reach the road. When we saw two at your truck, and we knew you'd think the soldiers had delayed us."

"Wise thinking, Sergeant." David nodded. "Speaking of lunch, there's a basket of sandwiches and apples here, and one in the back."

Shortly after four, David wheeled the lorry into the side courtyard of the Ambassador's residence, set the brake and switched off the magneto. "Here's your home for the night. Let's get the men unloaded and oriented, then we can do a full debrief."

Sonnenhang, Switzerland — Tuesday 26 October

After an early breakfast on Tuesday morning, David supervised the loading of two large trunks and a long wooden crate into the rear of the lorry. Once they had been securely lashed in place, cushions and pads were put on their tops, and the Sappers climbed aboard for the drive to Sonnenhang.

Ten to noon, less than half as long as doing it in the rain. David thought as he pulled to a stop in the courtyard, where he was greeted by Rachel and Georg.

After the Sappers were shown to their quarters, they returned to unload the crate of tunnelling equipment and lug it to the tool shed, then they carried the two trunks containing their work clothing to their quarters. Following introductions to the sabotage team, they all paused for lunch, David and Herman joining them.

When they had finished eating, David stood and addressed the group. "We have many pieces of the puzzle in place now. What we need is to see how they fit together." He motioned toward Herman. "Second Lieutenant Moberly and I will take Sergeants Perrier and Heiss to the site to discuss how to proceed. The remainder of you relax until we return. Probably not much more than half an hour."

As the four walked down through the vineyards, David talked with Sergeant Perrier. "Both Second Lieutenant Moberly and I have read the briefing papers on how your tunnelling is done. I think it best if we hear it directly from you."

They paused at the edge of the pasture and listened to the Sergeant. "We have four men per team; two kickers, a bagger and a trammer. The kickers work the face, the bagger gathers the spoils and puts them in bags, and the trammer hauls them out and returns with wooden setts. In clay, we can advance twenty feet per day. In chalk, like we suspect is under here, we'd be kept to half that or less, Sir. Much harder digging, but many fewer shoring setts required. For clay, we space them every nine inches, but for chalk, we'll need setts only every eight feet and at fractured areas."

David pointed down the sloping pasture and across to the two tool huts. "The water accumulation? You can see the slope here. How will you keep water from flooding your work space?"

"We need the tunnel to slope slightly upwards as we dig so water doesn't well against the working face. We'll start with a shaft to take us below the level of the destination." He uncased his inclinometer and sighted the average slope. "Can we go down to the edge of the next vineyard, Sir?"

"Yes, certainly, Sergeant." David led the way, explaining as they walked. "This is the area we had discussed that will be torn up to prepare it for vines."

They stopped at the edge of the small vineyard, and Perrier measured the slope to the second tool hut. He paced across the field fifty yards and stopped to measure the angle between the edge of the vineyard and each hut, adding the information to his notebook. Then after measuring the dip angles, he built a small cairn and paced back until the huts were aligned, from where he read and noted the angle and the inclination to the cairn.

Sergeant Perrier looked at his notes and sketches. "I'll do more precise measurements later, Sir. But these should give me sufficient to draw a sectional diagram. Guessing at the results of calculations and looking at the surroundings, I suggest we start the tunnel around here."

"That would certainly look less suspicious to the border guards." David pointed to the Customs posts. "We're in plain sight of the Germans here, but this is much better than having them see too much activity at the tool hut. Our field preparations should disguise your work well."

"That's why I proposed starting here, Sir." He smiled, then swept an arm around the area. "We try to take everything into account."

Ten minutes later, back in the mess, they all watched in silence as Sergeant Perrier sat and drew diagrams, then pulled out his trig tables to calculate distances. Within a few minutes, he held up a page with two labelled sketches. "This is approximate only, Sir, but it looks like we need to dig a sloping shaft down to about thirty feet. It's about a hundred and thirty-five feet between huts and two hundred twenty from the edge of the vineyard to the second one."

He pointed to the sketch. "If we start here, we'll need about two hundred and fifty feet of tunnel. All chalk will take us about a month. I suggest we build a new tool shed here to hide and protect the entrance and to house a water pump. We can begin our shaft while the hut is being built, Sir."

"A new tool shed is an excellent idea, Sergeant." David pointed at the sloping shaft on the cross-section sketch. "This appears steep."

"Forty-five degrees, Sir. There'll be a wooden ladder, almost like a staircase laying along it. Won't need to crouch going up or down because of the angle. But here," he pointed to the horizontal portion. "Here, through the main passage, we'll have to crouch with the five-foot height."

"What's our next step with this, Sergeant?"

"I'll take Corporal Bastarache, and we'll do precise measurements, and we'll also have some men do probes to test the soil structure. I should have detailed drawings and plans by day's end, Sir."

"I'll leave you to that." Then turning to the others, David added, "We won't be able to use the town's carpenters for the new shed. Our security is too likely to be compromised." He scanned the men's faces. "Who has carpentry experience?"

About half raised their hands. "That makes it easy. What about architectural drafting?" All looked around to see no raised hands. "Who can work with me to design a shed?" Everyone raised their hands.