Groundhogs and Bull Threshers

Threshing machines had to be pegged to the ground, in order to prevent them from disengaging from their tumble shafts during operation. This is thought to have contributed to the nickname groundhog thresher. The roaring sound created by the spinning cylinder also gave rise to the name bull thresher (670835). By the early 1850s, these machines were showing up in prize lists at Canadian agricultural fairs, and in manufacturers’ advertisements. Many manufacturers offered both a thresher and power source, emphasizing that the two pieces were specifically designed to work together.

Bull Thresher (670385)

A machine’s threshing capacity was determined by the width of its cylinder, and most groundhog threshers had cylinders measuring less than twenty-four inches in diameter. Unbound sheaves were fed headfirst into the machine by hand, where they were caught by the spinning cylinder and threshed between the teeth of the cylinder and concave. The kernels then had to be manually cleaned with a winnowing basket or fanning mill. Labourers were required to feed the sheaves into the machine, clean and bag the grain, and remove and stack the loose straw as it dropped off the conveyor. This type of machine could process 70 bushels of grain per day — a tenfold increase over the daily output of a single labourer using a flail.

Threshing machine manufactured by La Compagnie Desjardins (680860)

In the early 1860s, the “Little Giant Thresher” — a large groundhog thresher mounted on two wheels from the Stratford Agricultural Works of Stratford, Ontario — could be purchased for $100.00 cash, or $105.00 on approved credit. The four-horse sweep required to operate the machine cost an additional $100.00, or machine and sweep could be purchased together for $185.00. Soon, machines like the La Compagnie Desjardins (680860), featuring a slotted conveyor belt or endless apron and integral fanning mill, were introduced to the market. The conveyor carried the straw up and off the rear of the machine, and the chaff and kernels dropped through the machine’s slats into the hopper of the fanning mill, which was mounted under the conveyor.