A Cooper's Howel
rom the early 15th to the end of the 19th century a cooper was a skilled craftsman who made casks or barrels of various descriptions. A dry cooper made casks tightly sealed at both ends to hold grains and the like, a wet cooper made leakproof casks for liquids, and a white cooper made pails and tubs for domestic or dairy use. The word cooper originated in an old Dutch expression meaning cask.
A cooper's howel was a carpenter's plane mounted in a convex sole, which was used to champfer the inside edges of barrels' ends so the lids would fit snugly. The depth of the blade's cut was adjustable. The expedition carried at least two howels, according to Lewis's Philadelphia invoice summary. One of them was left in a cache at the mouth of the Marias River en route west. It is not known whether they took the other one with them or sent it back downriver on the returning barge.
A howel is but one of several specialized tools required by a cooper to make a barrel. Another is a long jointer to bevel the staves, and a third is a croze to groove the ends of the staves. However, the Corps of Discovery did not have an experienced cooper on their roster, and there is no evidence they took either a long jointer or a croze, and none that they ever needed to make any barrels (Lewis bought some extras in St. Louis). It may be that they took howels so that carpenters such as Patrick Gass could repair damaged or warped wet and dry barrels in order to restore tight seals to lids.