The ad for Rock Island Plow Co. shows the Illinois company made more than just tractors. Next to it, the little-known Wheat tractor shown in this 1919 ad from Alan King’s Year of the Tractor booklet was manufactured in Buffalo, N.Y. Some of the tractors shown in that booklet are little-known, like the Four-Drive, above, and the Indiana All-Round tractor, below. The booklet also contained ads like the one for Heider tractors. Alan liked to combine ads from different periods in some of his booklets, like this one for the Utilitor general purpose farm tractor.