DCHP-1 Online
key-log Lumbering 
1 n. the log which when released will free a jam (def. 2).
See also: jam ((n.)) (def. 2) key-piece key-stick lock-stick
- 1853 It may be thought best to cut off the key-log, or that which appears to be the principal barrier.
- 1894 Every hour's delay increased the tangle, and the difficulty of breaking the jam. The first thing necessary was to find the key log of the jam.
- 1964 We watched it [the driving boat] . . . go into quick action where river drivers loosened key logs in jams along the river.
2 n. the log retaining a pile of logs at the water's edge.
See also: brow (def. 2)
- 1964 When spring arrived the timber was released from its position on the shore; this was usually effected by moving the "key-log", located in such a position that it held all the others in place.
- 1853 It may be thought best to cut off the key-log, or that which appears to be the principal barrier.