ry good for Building.

This superfluous Humidity endamages Trees so much, that we are sometimes
constrain'd to make a hole at the foot of the Tree and let it run out,
which is the occasion of the Practice which is observ'd in cutting of
Wood for Building, to Tap that Tree at the Foot, cutting not only the
Bark, but even some part of the Wood it self, and so leave it for some
time before it be Fell'd.

[Sidenote: _Lib. 1. Chap. 5._]

It is likewise easie to judge of what great Importance the draining of
this superfluous Humidity is for strengthning the Timber, and hindring
Corruption, from this, That those Piles which are interlaced among the
Stones in the Walls and Fortifications of Towns endure for ever without
Corrupting, when they have been burnt a little on the outside.

[Sidenote: _Lib. 1. Chap. 11._]

[Sidenote: _Lib. 2. Chap. 8._]

Bricks ought not to be made use of but in very thick Walls; for this
reason they did not build with Brick in _Rome_, for to save Ground; they
were not permitted to make the Walls of their Houses above a Foot and a
Half thick, which Makes about 16 Inches and a half of our Foot.

They likewise never made the top of their Walls with Brick; for the
Brick of the Ancients not being baked, this part of the Wall would have
been easily endamaged; for this reason they built it with Tiles, a foot
and a half high, comprizing the Cornish or Entablature which was made
likewise of Tiles to cast off the Water and defend the rest of the Wall.
They likewise chose for these Cornishes the best Tiles, _viz._ those
that had been long on the top of the Houses, and given sufficient Proof
that they were well baked and made of good Matter.

The Walling with Brick was so much esteem'd among the Ancients, that all
their Fabricks, as well publick as private, and their most beautiful
Palaces were built with them. But that which principally made this sort
of Building be esteem'd, was its great Duration; for when expert
Architects were called to make an Estimate of Buildings, they always
deducted an 80th. part of what they judged the Building cost for every
Year that the Wall had been standing, for they supposed that the Walls
could not ordinarily endure more than Fourscore Years; but when they
valued Buildings of Brick, they always valued them at what they cost at
first, supposing them to be of an Eternal Duration.

To make the right use of Lime and Sand, and to make good Mortar of them,
it is necessary th