Model (scale 1:4). This model represents a double-blast threshing machine made in 1860 by Wallis, Haslam and Steevens. The machine was designed to be powered by a portable steam engine or, as the 19th century progresed, more often by an agricultural steam traction engine. Unlike earlier barn based-threshing machinery these threshers were mobile and were usually moved from job to job, either by horse power or, later, by the traction engine itself.
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