Oliver Evans’ Improved Grist Mill

Enlarge Image Image Gallery Winter in the Country – The Old Grist Mill by George Henry Durrie (1820-1863).

Flour was an important commodity to early American settlers. Many ground their flour in a pestle made of a hollowed-out tree stump. The mortar was a piece of log suspended over the stump by a rope from an overhanging branch or sapling. The spring action of the branch gave some lift to the mortar as the operator lifted and then dropped it to pound the grain into flour. Sometimes a crude stone hand grinder called a quern was used, but either process was slow and laborious. In an early account of frontier life in Ohio, the author writes: “I well remember that in 1791 so scarce and dear was flour that the little that could be afforded in families was laid by to be used in sickness, or for the entertainment of friends.” 

As the number of settlers in an area grew, some enterprising individual would build a water-powered mill along a stream. The neighboring farmers then made regular trips to the mill, carrying “grists” of grain to be made into flour. As fee for his services, the miller typically took one-tenth of the grist, an amount set by law in most states. Since farmers didn’t want to travel far for flour, mills sprang up everywhere, often only three or four miles apart. The early mills were slow, inefficient and labor intensive, and furnished many opportunities for contamination of the flour by dirt, insects and vermin.

Evans the innovator

Oliver Evans changed all that. Born in Newport, Del., on Sept. 13, 1755, at 16 Evans was apprenticed to a wheelwright who taught him to build wagons. Being curious and ambitious, the young man studied math, mechanics and science in his spare time and developed into an excellent “mechanician,” as they were called in those days.

Evans joined his two brothers in running a grist mill. Being inventive, he set out to improve the way flour was made. He designed bucket elevators to raise the grain and flour vertically and chutes to carry them back down, along with screw conveyors to move them horizontally through the mill. He also developed a rolling screen to clean the incoming grain before it was ground.

When freshly ground flour first came from the mill stones, it was hot and damp. To prevent caking, it had to be stirred while it cooled and dried. Standard practice was to spread the flour on the floor, where a miller’s boy stirred it with a hand rake until it was dry and cool. The procedure took a long time and was inherently unclean. Evans developed a machine, appropriately named a “hopper boy,” that performed the operation with a large mechanical rake inside an enclosed bin.