Starting in mid-17th century until mid-19th, several wooden cantilevered bridges were built in Japan. This one in Toyama prefecture, built 1663, was 63m long. But there was an even longer, in Shizuoka prefecture, which has an interesting backstory of environmental destruction.
In 1692 the bridge over the river Oi was rebuilt (the first bridge was built in 1607), at 72.8m. Unrelated, the same year logging operations started at a site 10km upstream. It was so badly managed that when it was stopped in 1700, 3600ha of forest had been clear cut.
The loss of the forest meant rainwater had nowhere to go except into the river which gradually grew wider and wider as it eroded the sides of the valleys it passed through. In 1700 the bridge had to be torn down and replaced with a new and longer one, at 85.5m.
In 1729 erosion still had not slowed down, and the old bridge was torn down once again, replaced with one that was 91m long. By comparison, the longest modern wooden cantilevered bridge is in Bhutan, at 56m, built by engineers using traditional methods in 2008.
Erosion slowed down as upriver logging was banned (authorities had caught up on what was happening) and the next, final, rebuild in 1825, when a 100.1m long bridge replacement was built, which lasted until the 1870s. Today the upstream is completely reforested and erosion halted.

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More from @wrathofgnon

27 Oct
The traditional "shophouses", can be found all over Asia (and beyond). In Phuket Old Town (Thailand), there are several streets preserved of this human scaled vernacular 1-3 story townhouses, examples of Sino-Portuguese style. This is South East Asian gold standard #GoodUrbanism.
A typical shophouse (whether in Phuket or Hanoi or Singapore or Kyoto) is a two story building in local materials, with a shop on the ground floor and living space above. The plots are deep and narrow to preserve valuable street frontage.
The style of the individual buildings is not the most important thing, they can be easily adapted even in modern materials, but the scale is unbeatable. The shophouses in Phuket are from the late 19th c. to the late 20th c., as these reinforced concrete buildings.
Read 5 tweets
26 Oct
Currently reading Losing Eden (2020) by Lucy Jones, a journalist discovering and investigating the importance of a connection to nature to our mental and physical well being while sobering up from a decades long drug and alcohol addiction. ImageImageImageImage
“In 2004, Mary O’Brien, an oncologist, discovered something fascinating by accident. She created a serum that contained M. vaccae, a species of bacteria found in soil. She wanted to see if the bacterium could boost the immune systems of her lung cancer patients...” — Lucy Jones ImageImage
“Scientists are starting to understand more deeply the role inflammation may also play in our mental health. Evidence that bodily inflammation can affect the brain and have a direct effect on mood, cognition and behaviour is relatively new. But it is strong and compelling.” — LJ ImageImage
Read 4 tweets
20 Oct
Know your natural street stone (left to right):
1. Cobbles, any shape without six clear sides.
2. Setts, quarried stones with six clear sides.
3. Cubes, setts with six identical sides.
4. Flags, flat stone slabs, often cut.
Often the price of materials goes up from cobbles to flags, and also user friendliness (cubes are often used in patterns which is beautiful but raises the price). In practice they are usually combined, in any possible combination, as in this charming street in Lincoln, England.
Except for cobbles, most stones are tooled (chiseled) to make the top side flatter. Some are sawn to ensure a perfect level top. Patterns can also be hammered or chiseled into stones for decorative effect or to help provide a better grip.
Read 5 tweets
14 Oct
Edo, (old Tokyo 16th/17th-late 19th c.) had a clever system to administrate half a million townspeople and keep the security at the same time: by delegation, to jishinban (left) and kidoban (right), a double set of guard posts at the entrance of each of the 994 town districts.
The jishinban (here illustrated as a book cover) was manned by the major landowner and his deputies, 3-5 at a time, answered for security and fire detection. It doubled as liaison office for civic administration: if you needed a birth certificate for ex., this was were you went.
The kidoban on the other side was manned by retired old men who lived there and kept the town gate closed from 10 P.M. to 6 A.M. Anyone wanting to enter after closing needed permission and kidoban guards would communicate comings and goings across the city using wooden clappers.
Read 5 tweets
24 Sep
Homelessness is a symptom that makes everything else much worse for everyone involved, not least the tax payer. The good thing is that we already know how to solve it. But as usual, there's no money in the cure, and riches to be made in the treatment.
theconversation.com/if-we-realised…
Build a couple of these and house the worst cases no questions asked. Simple food, simple lodging, simple clothing. Simple gardening and building work in return, staffed by ex-homeless and lay-brothers and sisters from monastic orders. Sex segregated.
You can fit an almshouse and its gardens on the parking lot of a typical supermarket. Make the rules as strict or as lenient as needed. Keep building them until everyone is housed, if there is ever a surplus, charge rent or start housing single elderly.
Read 5 tweets
23 Sep
This year's winner of the @DriehausPrize in the Building Arts in Spain, in the Glasswork category, are the beautiful family of master glassworkers, Vetraria Muñoz de Pablos, in Segovia. Outstanding stained glasswork. Do they take on foreign apprentices?
"My children and I have saved glass painting. Everything about the grisailles was lost, and we have seriously recovered it. Regardless, now that we know how to do it, somehow we need to pass it on." Image
"What we have learned in a workshop, in a disciple-master context, is not learned in standardized teaching... The workshop is a very important place to think, to act, to put mind and hand together... an almost spiritual communication." Image
Read 4 tweets

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