he tar; especially, in countries where work-men are so
very dear: But those knots above-mention'd, are provided to hand,
without any other labour, than the gathering only. There are sometimes
found of those sort of pine-trees, the lowest part of whose stems
towards the root is as full of turpentine, as the knots; and of these
also may tar be made: But such trees being rarely found, are commonly
preserved to split into candle-wood; because they will be easily riven
out into any lengths, and scantlings desir'd, much better than the
knots. There be, who pretend an art of as fully impregnating the body of
any living pine-tree, for six or eight foot high; and some have reported
that such an art is practis'd in Norway: But upon several experiments,
by girdling the tree (as they call it) and cutting some of the bark
round, and a little into the wood of the tree, six or eight foot distant
from the ground, it has yet never succeeded; whether the just season of
the year were not observ'd, or what else omitted, were worth the
disquisition; if at least there be any such secret amongst the
Norwegians, Swedes, or any other nation. Of tar, by boiling it to a
sufficient height, is pitch made: And in some places where rosin is
plentiful, a fit proportion of that, may be dissolv'd in the tar whilst
it is boiling, and this mixture is soonest converted to pitch; but it is
of somewhat a differing kind from that which is made of tar only,
without other composition. There is a way which some ship-carpenters in
those countries have us'd, to bring their tar into pitch for any sudden
use; by making the tar so very hot in an iron-kettle, that it will
easily take fire, which when blazing, and set in an airy place, they let
burn so long, till, by taking out some small quantity for trial, being
cold, it appears of a sufficient consistence: Then, by covering the
kettle close, the fire is extinguish'd, and the pitch is made without
more ceremony. There is a process of making rosin also, out of the same
knots, by splitting them out into thin pieces, and then boiling them in
water, which will educe all the resinous matter, and gather it into a
body, which (when cold) will harden into pure rosin. It is moreover to
be understood, that the fir, and most coniferous trees, yield the same
concretes, _lachrymae_, turpentines, and there is a fir which exstills a
gum not unlike the balm of Gilead, and a sort of _tus_; rosins, hard,
naval stone, liquid pitch, and t