Don't use linseed oil.  It becomes spar varnish on polymerization at
room temperature.  Boiled linseed oil sets fastest.  It would be useful
when diluted with a solvent as a hand-rubbing finish.  It is definitely
not good for lubricating wooden bearings.  Just sayin'!

For longer than I care to admit I have repeatedly asked (now dead)
machinists how they lubricated wooden bearings in elderly industrial
machinery.  The answers were, as one might imagine, many and
non-conclusive.  There is no single good answer.

My personal favorite is beeswax dissolved under heat in a mixture of
medium fraction (dodecane) petroleum ether and olive oil.  Don't try
this at home -- dodecane is volatile and flammable.  Hire a chemist or
college chemistry student.

A recent (2002) study of this topic is found in Roger Sathre's easily
understandable Master's Thesis,  "Improving the Performance of Hardwood
Journal Bearings", at

http://www.uidaho.edu/~/media/Files/orgs/CNR/Fire/Forest%20Products/Thesis%20and%20Abstract/Sathre2.ashx 

Your experience may vary depending on the condition, grain structure,
and composition of the wooden bearing as well as the surface finish of
the rotating shaft.

If you find yourself in a retro time warp doing new construction, use
lignum vitae and don't bother with lubrication at all.  It will wear
at the same slow rate no matter what you do.  If you are doing new
construction today use modern metal bearings.

W. F. Finch