In February 2022, Graeme Cavers and his crew of archaeologists set off looking for a mysterious underground passage referred to as a souterrain. There are round 500 of those Iron Age buildings scattered all through the Scottish Highlands, however no one is aware of what they had been constructed for, and nobody has ever found one intact.
“Maybe they had been for storage, corresponding to grain in sealed pots or dairy merchandise like cheese,” says Matt Ritchie, resident archaeologist at Forestry and Land Scotland. “Maybe they had been for safety, preserving valuables protected, or slaves or hostages safe. Or maybe they had been for ceremonial functions, for family rituals, like a medieval shrine or non-public chapel.”
Web site surveys may also help make clear the situation and construction of souterrains, however they’ll take not less than per week utilizing conventional strategies, says Cavers, whose firm AOC Archaeology was enlisted by Ritchie to assist map the Cracknie Souterrain in Scotland’s Borgie Forest.
Guide measurements utilizing a tool referred to as a theodolite—tough to make use of in darkish, cramped tunnels—have been changed by laser scanners, which have improved markedly previously few many years. “They used to hook up with an exterior laptop computer,” Cavers says. “The information might solely be recorded as quick as that connection. It was carried out over an Ethernet cable, so it was comparatively quick. However even then, the primary laptops that I used with a scanner had 2 gigabytes of RAM. That was prime quality. And a laptop computer price an terrible lot of cash in these days.”
The tech has developed a great distance since then. After crawling into the Cracknie Souterrain by a 50-centimeter opening within the floor, Cavers was handed a grey gadget the scale of a shoebox: a Leica BLK360 laser scanner.
Cavers set the gadget on a tripod within the dank 1-meter-high passage, adjusted a number of settings, and pressed “scan.” It swiveled into motion, firing a laser towards the partitions of the souterrain 10,000 occasions a second. Cavers and his crew can now take tens of millions of measurements in beneath an hour with out lifting a finger—Cracknie yielded 50 million in just some hours. “To do the equal of what we did with a theodolite, you’d be there a very long time,” Cavers says.
Accumulating massive knowledge units presents a problem in itself. “At this time, we’re coming again with half a terabyte” of knowledge, he says. “And we’d do a few hundred tasks in a yr. It begins to get very tough to handle from an IT perspective. And clearly we’re archaeologists; we’re purported to be creating archives which might be perpetual, for the long run.”
The information does, nevertheless, pay its dues. Cavers would have as soon as had to attract or {photograph} the souterrain from throughout the darkish passageway, which might have challenged his perseverance with none pure gentle. Now he makes use of software program—Trimble RealWorks, NUBIGON, and Blender—to supply accessible 3D multicolored “level cloud” fashions.
The crew members can then take a look at the fashions from any angle they like and measure distances between any two objects, and so they can change the colours in accordance with variables corresponding to peak and density. It means archaeologists like Ritchie can educate folks about archaeological websites with out having to really go there.
“[Cracknie] may be very distant,” Ritchie says. “It’s a great distance from established strolling routes and is comparatively tough to entry.” Which means it’s poorly suited to guided excursions or instructional panels—however a 3D mannequin will be considered from anyplace. Ritchie might even print out a scale mannequin and show it in a museum. The know-how is making Britain’s cultural heritage extra accessible, and may in the future assist archaeologists like Ritchie remedy the thriller of Scotland’s souterrains.
This text was initially revealed within the January/February 2023 problem of WIRED UK journal.