16. Staffelbach
In Giornico, since 1937, a granite warrior has been pushing a boulder that does not move. In October 2016, in Aargau, a worker makes the same gesture.
This time the boulder really moves: a 124-tonne erratic, moved five hundred metres with a special crane and a lorry.
The boulder had been found the year before in a gravel pit, and the find had been described as exceptional. The rock is about 164 million years old. The block is more than five metres long and about three high, with a volume of some forty cubic metres: the largest ever recovered from a gravel pit in Aargau. It was found by one of the company’s machine operators. “At first I thought I had hit the bedrock with the bucket,” he said.
The stone is a calcareous sandstone. That is its oddity: erratic boulders are normally crystalline rocks, granites, robust materials that withstand the journey. A sandstone is a sedimentary rock, not very resistant to weathering, and should not arrive down here intact. That it did means it travelled embedded in the ice, and protected by it.
It was deposited here about twenty-six thousand years ago by a lateral arm of the Reuss glacier, descending from the canton of Uri, during the Last Glacial Maximum, the moment when the glaciers advanced furthest onto the Swiss Plateau. The terminal moraine that contained it is still there.
A hundred kilometres were covered by the ice. Five hundred metres were covered by us.
It is the five hundred metres that have a date, a time and photographs.
The boulder was placed at the entrance to the gravel company’s works, at the entrance to the village, to be preserved, so the news report says, for future generations.
It was thus placed in front of the gate of the company that would otherwise have crushed it.
No one carved it. No one altered its form. It was enough to move it five hundred metres and set it down at the point where one enters the village: from that moment it is a monument.
It is the same position that Pessina’s warrior occupies in Giornico.
But there, someone had to carve a boulder out of granite to achieve the effect.
Here it was enough to take the boulder.
In the photographs of the operation the worker has his hands on the boulder hanging from the chains, his body leaning forward. With one difference from the warrior of Giornico: this man moves nothing. The weight is all the crane’s. The gesture has outlived its own necessity.
Then there is a line in the news report that is worth a whole chapter.
By law, in Switzerland, erratic boulders weighing more than ten tonnes belong to the canton.
This boulder is therefore the property of the canton of Aargau. The cantonal environmental department examined it together with ETH Zurich and declared it worthy of protection.
There is thus a threshold of mass beyond which a stone ceases to be landscape and enters the law. Below ten tonnes it is a rock, and whoever owns the land owns it too. Above, it is public property. The foreign body that the landscape has accepted also has an owner.
The same report adds that most erratic boulders were used for the construction of buildings.
The ones we can point to today are the survivors. The others are walls, thresholds, foundations: sound stone in plains poor in good stone, and therefore open-air quarries already squared by nature.
The most famous of those saved stands at Monthey, in Valais. The Pierre des Marmettes, an enormous block of Mont Blanc granite, was destined to be reduced to building material. In 1906 the Swiss Society of Natural Sciences bought it for thirty thousand francs; since 1908 it has belonged to the Swiss Academy of Sciences. The committee formed to save that boulder is the same one that shortly afterwards promoted the creation of the Swiss National Park.
Nature conservation in Switzerland begins with buying a rock.
It is not the first boulder moved to make way for a public work. On 15 October 1973, in Göschenen, the Teufelsstein, the great boulder that according to legend the devil hurled at the valley, was moved some sixty metres to make room for the Gotthard motorway.
There the reason was the opposite: the boulder was not to be put on show, it was to be got out of the way. But the legend did not stay in its place. It followed the boulder.
The legend remains. The boulder moves.
A few months after it was set in place, a long vertical crack appeared on the boulder, and the local press wondered whether it was about to split in two. The cantonal geologist explained that the crack was already there before the transport: rain and snow had washed away the soil and made it visible.
It is not the boulder that has split. It is its fracture that has been discovered.
The new location was chosen by the canton together with the municipality, and it was not easy: it had to be accessible to the public and at the same time remain close to the place of discovery. Not only because of the cost of transport, nineteen thousand francs for five hundred metres. The cantonal geologist explained the reason: the boulder has value only if it stays near the place where it was found, because only there does it demonstrate the force of the glacier.
An erratic moved too far ceases to be evidence and becomes an ornament.
Every erratic boulder we can point to today has been chosen twice: once by the ice, once by us.
Translation: Archivio Umberto Cavenago
Staffelbach, October 2016. Lifting the 124-tonne erratic boulder.
Photo © Aargauer Zeitung
Staffelbach, October 2016. Lifting the 124-tonne erratic boulder.
Photo © Aargauer Zeitung
Lowering onto the trailer.
Photo © Aargauer Zeitung
The boulder in its current location, at the entrance to the works. The vertical crack was already there before the move: rain and snow washed away the soil and made it visible.
Photo © Aargauer Zeitung
The boulder hanging from the chains, before being lowered onto the trailer.
Photo © Aargauer Zeitung
Transport along the road: five hundred metres.
Photo © Aargauer Zeitung
The Teufelsstein in Göschenen, moved in 1973 to make way for the Gotthard motorway. It is 12 metres high and weighs about 220 tonnes.
Photo © Roland Zumbühl, CC BY-SA 4.0 (Wikimedia Commons)