Chinking is best done from the inside. Long triangular strips and blocks of wood are driven in between the logs and fastened there with oak pins driven into the lower log till nothing but small crannies remain. Some cabins are finished with moss plugged into all the crannies, but mud worked into plaster does better.
It should be put on the outside first, and afterward finished form the inside. It is best done really with two plasterers working together, one inside and one out.
This completes the shanty, but a bunk and fireplace are usually added.
The fireplace may be in one corner, or in the middle of the end. It is easiest to make in the former.
Across the corner, peg three angle braces, each about three feet long. These are to prevent the chimney falling forward.
Now begin to build with stone, using mud as mortar, a fireplace this shape. (Fig. 9.) Make the opening about eighteen inches across; carry it up two feet high, drawing it in a little, then lay a long stone across the front, after which build up {63} the flue behind the corner braces right up to the roof. The top corner-piece carries the rafter that may be cut off to let the flue out. Build the chimney up outside as high as the highest part of the ridge.
But the ideal fireplace is made with the chimney on the outside of the cabin, at the middle of the end farthest from the door. For this you must cut a hole in the end log, like a big, low window, pegging a jamb on the ends as before.
With stones and mud you now build a fireplace inside the shanty, with the big chimney carried up outside, always taking care that there are several inches of mud or stone between the fire and any of the logs.
In country where stone cannot be found, the fireplace is often built of mud, sustained by an outside cribbing of logs.
If the flue is fair size, that is, say one quarter the size of the fireplace opening, it will be sure to draw.