Ex-Pat wrote:Makes sense, although not a British thing (that I have ever come across).
They were used extensively on narrow gauge lines in the UK in their various forms. Many forestry commissions used to use narrow gauge lines and they would lay the track to where they needed as one would do if one had a sectional track trainset, and they used horse drawn power as they could negotiate steep 1 in 4 gradients as horses could get traction. They would use waggons as a pair like this to then take freshly cut trees down to the sawmills for further processing.
There was no specific railway in many cases as the track was layed down or taken up as it was needed though a few lines did have semi-permanent sections nearer to the sawmills and the rest of the line was moved in sections to the area it was needed.
They were only seen with locomotive power where the more permanent flatter areas where many pairs of waggons could be towed together. If a severe gradiented area was used on a regular bases, they would build a cable incline, but most of these forestry lines were by their nature temporary lines, so they would use horses for going up and ropes, pulleys and sprags etc for going down. (Whatever was the most suitable solution bearing in mind rhat the line was to be moved when the work had been done).
Some such lines would only been needed on the flatter gradients as horses could simply drag trees down to them for loading without the need for any mechanised means.
...Sorry Ex-Pat, this is a misunderstanding: the only wooden parts are the four pieces forming the main frame.
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