of the Blue Gum of Tasmania, ce. 127 
not given to seasoning in the Colonies, the wood being suit- 
able for ship-building in a half-seasoned or even green state. 
A saving of time is effected when it is used green, and it 
then works more easily; but it is questionable whether pro- 
perly seasoned timber would not, in regard to durability, be 
the best—though in this respect it is boasted that the age of 
the Colony is not sufficient to test it. In ship-building, 
however, a surface coating of tar is almost invariably used, 
which is stated to prevent opening or rending. It probably, 
by checking undue evaporation at the surface, causes the 
seasoning to progress more uniformly. The plank for the 
topsides of ships and flooring-boards of houses ordinarily 
undergoes a seasoning of from one to three years previous 
to use. The Table of Experiments shows that the longer it 
is seasoned the stronger it becomes. 
The rationale of seasoning appears to be simply this :—A 
tree, at the time when it is felled, is filled with moisture from 
the sap and juices peculiar to its kind: these are mostly 
subject to fermentation, and consequently contain within 
them germs of vegetation. The object is to check this power 
of vegetation, and to bring the wood as nearly as possible 
into a state of unvarying density. This is effected by drying; 
and the slower the process is conducted, the better for the 
quality of the wood, which, when once thoroughly dried and 
preserved so, will remain sound for centuries. But vegetation, 
though checked in this way, is not destroyed—the principle 
remains dormant, as in the case of the mummy wheat; and 
will spring into action on the approach and continued pre- 
sence of moisture. A small fungus is then generated, usually 
termed the rot, which feeds upon the substance of the wood, 
destroying the cohesion of the fibre, and converting the whole 
into its own residuum or dust. 
The juices of trees appear to be of lighter specific gravity 
