Wednesday, August 9, 2017

Bridging Gaps, Gorges, Streams and Rivers in Yunnan


                          by Jim Goodman

crossing a river at Pula, Gongshan County
        With much of its topography characterized by steep mountains, deep valleys and swift flowing rivers, Yunnan has always been a difficult place to get around.  That’s not so obvious today, for paved roads have penetrated the most remote areas, tunneling through the mountains when necessary, and modern bridges span many points on the rivers.  Such things didn’t exist in ancient times, though, when fissures in the rocky landscapes and streams that were too dangerous to cross on foot or swim through and migrants or even hunters had to devise a way to get to the other side or be restricted to a limited environment.
       If it were a very narrow defile, and climbing down the cliff to cross the stream, even if one could wade through it, was just too much trouble, one could solve the problem by felling a tree on one side to reach the other side.  If it were to be on a permanent route, then folks would anchor it more securely on each side.  Or they might substitute a few sturdy bamboo poles lashed together, wide enough to walk upon, with a cable of some kind on each side to hang on to and not fall.
bamboo plank bridge above Gongshan
riding a rope-bridge in Nujiang
       Another primitive kind of bridge was a rope made of vine, tied to tree trunks on each side, over which people crossed by hand.  These couldn’t have been very long, but the concept evolved into a more sophisticated kind of rope-bridge, especially employed in the canyons of the Three Rivers region (Nujiang, Lancangjiang and Jinshajiang) of northwest Yunnan.
Lisu women crossing the Nu River near Lumadeng
       These usually came in pairs, with the starting point higher on each side than the landing point on the opposite bank.  Hence, they were called ‘tilting ropeways.’  The ropes were made of plaited split bamboo, the same kind used to haul boats at the ports on the Yangzi.  To make them people stripped off the outer layer of the bamboo, 3 mm wide, planed the strips to make them smooth and then plaited them. 
       Bamboo is a very special and strong plant.  These split bamboo ropes had a tensile strength nearly equal to that of steel.  They never broke.  To ride one across the canyon, one sat in a rope harness attached by hooks to the cable rope and hold one hand on a slider on the rope, to keep the hand from getting singed holding onto the cable.  The passage proceeded at a moderate speed, but sometimes the momentum would give out before reaching the other side.  Then riders had to haul themselves by hand the remaining distance.
suspension bridge at Dulongjiang
early 20th c. Nujiang trail (from the Morse family archives)
     Another quality of the bamboo ropes, valued by the boat-haulers on the Yangzi river, was that, instead of deteriorating under water for prolonged periods, the immersion actually strengthened them.  While the rope-bridges in Yunnan were never under water, they were certainly subjected to monsoon rains.  Though they never broke, under long heavy stress, like the passage of a caravan, they began to sag and had to be replaced.  (The government replaced split bamboo ropes with wound steel cables in the 1950s.)
Duoyi RIver bridge, Luoping County
       Nujiang Canyon, in western Yunnan’s borderlands with Myanmar, experienced many of these caravans in the old days.  With no suspension bridges in place, they had to cross the river by rope-bridge, with all their cargo and animals.   This could be very time-consuming, especially for a large caravan, and might require two or three days.  Also, the rope-bridges would probably begin to sag partway through the crossing, when animals would be stuck on them before they reached the end.  Then men had to slide down and pull the frantic animal the remaining distance.  Inevitably, a major caravan crossing required replacing the ropes at least once.
bamboo bridge, Menglian County
       According to the Nu minority nationality in the northern part of the canyon, their goddess Areng created the rope-bridge.  She was pining for a lover on the other side of the river and to get to him she fired a rope from a giant crossbow to land on the opposite bank and then scampered across the rope.  That’s the mythological explanation, but it’s still a mystery how people installed the rope-bridges in the first place.  Most of them crossed rapids, so people couldn’t block off the flow of the river to cross on foot, take the rope with them and then secure it on the other side.
       For smaller, less turbulent streams, folks could temporarily dam up the water flow and transport the building materials.  Bamboo served the purpose in most cases.  Some would consist of bamboo poles lashed together for the part to walk across, with long bamboo poles on either side to hold on to.  Long bamboo poles on each side could intersect in an arc over the center, to contribute to the stability of the bridge.
bamboo bridge, Luchun County
       Bridge-builders could also cut the bamboo into planks or plaited strips and lay them horizontally over the walking part, or deck, supported by long cables that were anchored firmly to each side.  Such bridges would sway a little bit when people crossed them, especially carrying heavy loads or leading animals, but they always had poles or, later, iron cables on each side to grasp and keep one’s balance.  Quite sturdy and durable, they are still in use in various parts of Yunnan.
       With the introduction of iron as a construction element, suspension bridges grew more sophisticated.  Iron chains lay under the wooden or bamboo planks of the bridge and were fastened to iron anchors at each end that were encased in stone.  In some cases there were no planks at all and people crossed by walking carefully on one of the chain links, hanging onto the guardrails on the side.  This called for some balancing skills, and animals never used such chain link bridges, but apparently people preferred this to negotiating on foot through the boulders and torrents below.
Yunlong Bridge,Yangbi
modern suspension bridge in Jinghong
       Iron-reinforced suspension bridges could bear a heavier load, so these were built along the main trade routes—the Southern Silk Road and the Tea and Horses Road.  These could support the passage of a hundred baggage-laden animals and their handlers and the crossing could be done in several minutes, rather than the two or three days required in Nujiang, which didn’t have any suspension bridges over the Nu River until after the mid-20th century.  Moreover, the iron cables didn’t sag from continual use, so didn’t have to be replaced.
Belt Bridge, Black Dragon Pool Park, Lijiang
      Highways have replaced the ancient trails and trucks have taken over from caravans.  But a few of the old bridges remain.  The most accessible is the Yunlong Bridge in Yangbi, on the other side of the Cangshan Mountains, west of Dali.  Yangbi was a stop on the old Bonan Road north to Shaxi and Jianchuan and west to Yongping and Baoshan. 
       Built in the Ming Dynasty, 53 meters long, 2.3 meters wide and 12.9 meters above the Yangbi River, it consists of nine iron cables, with wooden planks over them, cables on the sides and blockhouses at each end.  The bridge is still in regular use by local villagers, who bring their animals when coming to Yangbi for market day.  Caravans ceased using it decades ago.  The new commercial highway passes south of Yangbi and does not run over the old Bonan Road.  This probably spared the Yunlong Bridge from being replaced by a more modern suspension bridge, like the kind constructed al over the province in recent decades, both for vehicles and for pedestrians only, supported by iron cables sling between towers over pillars below the deck. 
the Old Stone Bridge in Dayan, Lijiang
       Such suspension bridges are common throughout the world and in some cases are tourist attractions (Golden Gate in San Francisco, for example).  But another kind of bridge, made of stone, with arches and a rounded walkway, was also associated with China.  When the French Mekong Expedition in the 1860s crossed into China in Xishuangbanna, they didn’t really feel they were in China proper until they left Xishuangbanna, went north to Simao (now renamed Pu’er) and saw an arched stone bridge.  Ah, that was an image of China they were familiar with, expected to see, and confirmed that they were now in the China of their imagination.
       The Expedition’s chroniclers didn’t comment on any other arched bridges, but the phenomenon existed throughout the province.  Besides spanning rivers, they were also used to connect to pavilions or shrines in temple ponds.  In the latter case, with the round arches reflected in the water, the viewer sees an aesthetically pleasing row of circular images.  The pathway on the bridge could be straight or slightly higher in the center, with the biggest arch in the center and arches of diminishing size on either side.  A good example is the Belt Bridge in Lijiang’s Black Dragon Pool Park.
arched stone bridge in Shaxi
       Lijiang’s other famous bridge, also arched, spans one of the streams running through the Dayan old town.  Called the Old Stone Bridge, and one of the very few original structures left in the old town, it dates to the early Ming Dynasty.  Kubilai Khan is supposed to have pitched his camp here when he arrived after his army crossed the Jinshajiang on Naxi-supplied goatskin rafts.  Naxi communities then lived further north in the plain and Dayan grew up beside the Old Stone Bridge only after the Khan’s departure.
       Folks in the towns and countryside also built arched stone bridges over their streams.  Usually they had but a single large arch that made the center of the bridge two or three meters higher than the entrances on each side.  Supposedly, this was to allow small boats with sails, or more likely rafts with people standing up in them, to pass under the bridge.  Some of the highly arched bridges had a kind of staircase to use.  The stone bridges were generally wider than suspension bridges, often with stone guardrails on the sides and animal sculptures at the ends.
Double Dragon Bridge, Jiamshui County
       Such bridges are still in use throughout the province.  Where they exist in or near towns they are especially active on market days.  People carry their goods and lead their animals across them and because of the high arched middle, vehicles like cars, motorbikes and even tractor-trailers usually avoid them.
       Multiple-arch bridges also used odd numbers, like three, five or seven.  This was especially necessary, aesthetically speaking, if the middle of the bridge rose higher than the ends.  Then the largest arch was directly in the center and an even number of arches had to flank on each side to give it overall visual balance.  The bridges were, after all, a kind of art form, and had to be guided by principles of harmony.
covered bridge over the Yongchun River, Weixi County
       Of all of Yunnan’s classic stone bridges, Shuanglongqiao (Double Dragon Bridge) in Jianshui County, has the most arches.  Originally constructed in the late 18th century with just three arches and a three-story central tower, because the river started getting wider and the bridge couldn’t cross all of it, the local governor had it expanded to seventeen arches, with an additional, smaller tower at one end.
       Today it’s difficult to imagine why the extension was necessary.  Except after the heaviest monsoon rains, the river is so narrow and shallow it only passes under a few of the arches.  Under most arches the land is dry and local people walk under the bridge more often than over it.  While the location is not far from Jianshui, it is not near a heavily populated rural area and seems to have been of limited commercial value.  Nevertheless, it is one of the most beautiful bridges in the province.
covered bridge near Chongxin, Yunlong County
       Other arched stone bridges featured a tower over the center, a place to shelter in a sudden storm, a feature that may have inspired another type of Chinese bridge:  the Wind and Rain Bridge (fengyuqiao).  This had a roof over the entire span of the bridge and wooden walls along the sides.  They were so named because they provided protection against wind and rain, not just for people who happened to be traveling that way, but undoubtedly for farmers who were in nearby fields.  They even had benches installed inside and racks to put loads or baggage.
       Centuries after their construction, many of these are still in use, especially in the west.  Weixi, Yunlong and Tengchong Counties have several along some of the main routes.  Sometimes the covered bridge spans such a small stream, where there are alternative routes to get to the main paths, that one wonders why they even built it.  Maybe they just wanted something beautiful in their environment, a landmark that reflected their pride and aesthetic taste.
       Covered bridges service communities that are remote, off the beaten track, not part of important commercial networks and not in areas targeted for development.  Therefore, they won’t need to be replaced by something bigger, sturdier and more modern looking.  They will remain standing in the countryside as a testimony to the ingenuity of Chinese engineers, with their special aesthetic touch.

coming out of the covered bridge at Baoluo,Yunlong County
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