If your logs are uneven and leave large spaces between them, they may be
chinked up by filling the spaces with mud plaster or cement, and then
forcing in quartered pieces of small logs and nailing them or spiking them
in position. If your logs are straight spruce logs and fit snugly, the
cracks may be calked up with swamp moss (Sphagnum), or like a boat, with
oakum, or the larger spaces may be filled with flat stones and covered
with mud. This mud will last from one to seven or eight years; I have some
on my own log cabin that has been there even a longer time.