Covered Bridges continued:-
Covered bridges are first seen in history in the early 1300’s in Switzerland and the around Europe up to the late 1500’s when they seemed to go out of fashion. They re-appeared in America in the 1700’s with their normal simple king-post trusses, in which the roadway was supported by a pair of heavy timber triangles. Then New England carpenters developed bridges combining simplicity of construction with their other economic advantages. The first long covered bridge in America, with a 180-foot centre span, was built by Timothy Palmer from Massachusetts in 1806. A New Haven architect named Ithiel Town patented the Town lattice, in which a number of relatively light pieces, diagonally crisscrossed, took the place of the heavy timbers of Palmer’s design and of the arch. Another highly successful type was designed by Theodore Burr of Torrington, this combining a Palladio truss with an arch. Many of Town’s and Burr’s designs remained standing to this day, some dating back to the early 19th century.
So why were covered bridges built? It is commonly thought that the purpose of the covers on the roof and/or sides of the bridge was to keep snow off the road and to provide shelter for travellers during storms. In areas with very high snowfall, such as Vermont, the weight of snow could demolish a wooden bridge and a sloping roof did allow the snow to fall harmlessly into the river. However in New England and the Mid-West winter traffic was not on wheels but on sleds. Consequently most bridges had minders who, when it snowed, shovelled some back onto the bridge so sleds could cross.
However the fact of the matter is that the covers were designed to protect the bridge itself. Constant exposure to sun, snow, and rain meant that wooden bridges had a useful life of about ten years. A roof and side walls were applied to keep the trusses dry. Moisture trapped in the joints would cause the wood to rot and, in winter, the moisture would expand when it froze, which would weaken the truss, eventually leading to the collapse of the bridge. Once it had a roof to protect the structural supports from the elements, a bridge could last a century or more.
Covered bridges began to be built across Kentucky rivers and creeks in the late 1700s; many being the work of bridge architect Lewis Wernwag.
The longest wooden covered bridge in the world once stood near the town of Butler in Pendleton County, Kentucky. The 456ft Butler Station Bridge was made up of three spans of 152 feet each. The bridge was built in 1870 at a cost of $18, 450. It was severely damaged by winds and floods 1937, which caused it to be torn down that September.
The loss of Kentucky' s covered bridges began during the Civil War when many were burned by troops on both sides of the conflict. The number of bridges continued to decline through the 20th century. All of Kentucky' s remaining covered bridges are now listed on the National Register of Historic Places. Now that we know all about them let’s see where you can find them.
Covered Bridges continues in part 43.
Covered bridges are first seen in history in the early 1300’s in Switzerland and the around Europe up to the late 1500’s when they seemed to go out of fashion. They re-appeared in America in the 1700’s with their normal simple king-post trusses, in which the roadway was supported by a pair of heavy timber triangles. Then New England carpenters developed bridges combining simplicity of construction with their other economic advantages. The first long covered bridge in America, with a 180-foot centre span, was built by Timothy Palmer from Massachusetts in 1806. A New Haven architect named Ithiel Town patented the Town lattice, in which a number of relatively light pieces, diagonally crisscrossed, took the place of the heavy timbers of Palmer’s design and of the arch. Another highly successful type was designed by Theodore Burr of Torrington, this combining a Palladio truss with an arch. Many of Town’s and Burr’s designs remained standing to this day, some dating back to the early 19th century.
So why were covered bridges built? It is commonly thought that the purpose of the covers on the roof and/or sides of the bridge was to keep snow off the road and to provide shelter for travellers during storms. In areas with very high snowfall, such as Vermont, the weight of snow could demolish a wooden bridge and a sloping roof did allow the snow to fall harmlessly into the river. However in New England and the Mid-West winter traffic was not on wheels but on sleds. Consequently most bridges had minders who, when it snowed, shovelled some back onto the bridge so sleds could cross.
However the fact of the matter is that the covers were designed to protect the bridge itself. Constant exposure to sun, snow, and rain meant that wooden bridges had a useful life of about ten years. A roof and side walls were applied to keep the trusses dry. Moisture trapped in the joints would cause the wood to rot and, in winter, the moisture would expand when it froze, which would weaken the truss, eventually leading to the collapse of the bridge. Once it had a roof to protect the structural supports from the elements, a bridge could last a century or more.
Covered bridges began to be built across Kentucky rivers and creeks in the late 1700s; many being the work of bridge architect Lewis Wernwag.
The longest wooden covered bridge in the world once stood near the town of Butler in Pendleton County, Kentucky. The 456ft Butler Station Bridge was made up of three spans of 152 feet each. The bridge was built in 1870 at a cost of $18, 450. It was severely damaged by winds and floods 1937, which caused it to be torn down that September.
The loss of Kentucky' s covered bridges began during the Civil War when many were burned by troops on both sides of the conflict. The number of bridges continued to decline through the 20th century. All of Kentucky' s remaining covered bridges are now listed on the National Register of Historic Places. Now that we know all about them let’s see where you can find them.
Covered Bridges continues in part 43.