The early pioneer equipment manufacturers were never short of ideas to incorporate into their products. Take, for example, this early 1920’s road grader made by the Sawyer Massey Company of Hamilton.
Prior to this, graders were primarily pulled by horses, or later by steam rollers, an arrangement that was not only cumbersome but limited in its capability. How to make one with its own power was their problem, unable to develop their own power unit, transmission and drive axle.
What evolved was quite original and effective, and although the concept was only used for some ten years in production, it enabled them to take grader development to the next stage. A standard farm tractor, whose development had reached the stage where they were no longer huge gasoline engine conversions of a steam traction engine, was built into the rear portion of the grader. With the rear wheels and drive axle left in place to power the grader, the front axle of the tractor was removed and replaced with a supporting bracket.
Initially, a Fordson tractor was used, as shown above, and later a McCormick Deering tractor, a product of the International Harvester Company took its place.
Bingo, a first for Ontario, a self-propelled grader
For more, see my book Steam Engines and Threshers