1Iron ones. If Lead is daubed with any Sort
of Filch, it quickly ſpoils; and for this Reaſon
we ſhould take Care that our Roof be not a
convenient Harbour for Birds; or if it is a like
ly Place for them to get together in, we ſhould
make our Stuff thick where their Dung is to
fall. Euſebius tells us, that all round the Top
of Solomon's Temple there was a great Number
of Chains, to which hung four hundred little
Bells continually vibrating, the Noiſe of which
drove away the Birds. In the Covering we
alſo adorn the Ridge, Gutters and Angles, by
ſetting up Vaſes, Balls, Statues, Chariots and
the like, each of which we ſhall ſpeak of in
particular in its due Place. At preſent I do
not call to Mind any thing further relating to
this Sort of Ornaments in general, except that
each be adapted to the Place to which it is
moſt ſuitable.
of Filch, it quickly ſpoils; and for this Reaſon
we ſhould take Care that our Roof be not a
convenient Harbour for Birds; or if it is a like
ly Place for them to get together in, we ſhould
make our Stuff thick where their Dung is to
fall. Euſebius tells us, that all round the Top
of Solomon's Temple there was a great Number
of Chains, to which hung four hundred little
Bells continually vibrating, the Noiſe of which
drove away the Birds. In the Covering we
alſo adorn the Ridge, Gutters and Angles, by
ſetting up Vaſes, Balls, Statues, Chariots and
the like, each of which we ſhall ſpeak of in
particular in its due Place. At preſent I do
not call to Mind any thing further relating to
this Sort of Ornaments in general, except that
each be adapted to the Place to which it is
moſt ſuitable.
CHAP. XII.
That the Ornaments of the Apertures are very pleaſing, but are attended with
many and various Difficulties and Inconveniences; that the falſe Apertures
are of two Sorts, and what is required in each.
many and various Difficulties and Inconveniences; that the falſe Apertures
are of two Sorts, and what is required in each.
The Ornaments of the Aperture give no
ſmall Beauty and Dignity to the Work,
but they are attended with many great Diffi
culties, which cannot be provided againſt
without a good deal of Skill in the Artificer,
and a conſiderable Expence. They require very
large Stones, ſound, equal, handſome and rare,
which are Things not eaſily to be got, and
when got not eaſily removed, poliſhed, or ſet
up according to your Intention. Cicero ſays,
that the Architects owned they could not ſet
up a Column exactly perpendicular, which in
all Apertures is abſolutely neceſſary both with
Reſpect to Duration and Beauty. There are
other Inconveniencies beſides; which, as far as
lies in our Power, we ſhall endeavour to pro
vide againſt. An Aperture naturally implies
an Opening; but ſometimes behind this Open
ing we run up a Wall which makes a Kind
of falſe Opening which is not pervious but
cloſed up; which for this Reaſon we ſhall ac
cordingly call a falſe Aperture. This Sort of
Ornaments, as indeed were moſt of thoſe
which ſerve either to ſtrengthen the Work or
to ſave Expence, was firſt invented by the
Carpenters, and afterwards imitated by the
Maſons, who thereby gave no ſmall Beauty to
their Structures. Any of theſe Apertures would
be more beautiful if their Ribs were all of one
Piece, made of one entire Stone; and next to
this, is the having the Parts ſo nicely joined
that the Joints cannot be ſeen. The Ancients
uſed to erect their Columns and other Stones
which ſerved as Ribs to theſe falſe Apertures,
and fix them firm on their Baſes, before they
carried up the Wall; and herein they did very
wiſely; for by this Means they had more Room
to uſe their Engines, and could take the Per
pendicular more exactly. You may plant your
Column perpendicular upon its Baſe in the fol
lowing Manner: In the Baſe and at the Top
and Bottom of the Column mark the exact
Center of each Circle. Into the Center of the
Baſe faſten an iron Pin, ſoddering it in with
Lead, and make a Hole in the Center of the
Bottom of the Column, juſt big enough to re
ceive the Pin which ſticks up in the Center of
the Baſe. In the Top of your Engine, or
Scaffolding, make a Mark exactly perpendicu
lar over the Pin which ſticks up in the Center
of the Baſe, which you may find by letting ſall
Line from thence to that Pin. When you
have thus prepared every Thing, it will be no
hard Matter to move the Head of the Shaft
till its Center anſwers exactly to the Mark
which you have made above and is perpendi
cular to the Center of its Baſe. I have obſerv
ed from the Works of the Ancients that the
ſofter Sort of Marble may be ſmoothed with
the very ſame Inſtruments with which we
plane Wood. The Ancients alſo uſed to ſet
up their Stones quite rough, only ſmoothing
the Heads and Sides of them which were to
join to other Stones, and aſterwards when the
Building was raiſed, they poliſhed the Faces of
the Stones, which they had leſt rough before;
and this I believe they did that they might
leave the leaſt Expence that was poſſible to the
Hazards of their Engines: For it would have
been a much greater Loſs to them, if by Acci
dent any Stone that was quite ſmoothed and
poliſhed had been let fall and broke, than if
ſmall Beauty and Dignity to the Work,
but they are attended with many great Diffi
culties, which cannot be provided againſt
without a good deal of Skill in the Artificer,
and a conſiderable Expence. They require very
large Stones, ſound, equal, handſome and rare,
which are Things not eaſily to be got, and
when got not eaſily removed, poliſhed, or ſet
up according to your Intention. Cicero ſays,
that the Architects owned they could not ſet
up a Column exactly perpendicular, which in
all Apertures is abſolutely neceſſary both with
Reſpect to Duration and Beauty. There are
other Inconveniencies beſides; which, as far as
lies in our Power, we ſhall endeavour to pro
vide againſt. An Aperture naturally implies
an Opening; but ſometimes behind this Open
ing we run up a Wall which makes a Kind
of falſe Opening which is not pervious but
cloſed up; which for this Reaſon we ſhall ac
cordingly call a falſe Aperture. This Sort of
Ornaments, as indeed were moſt of thoſe
which ſerve either to ſtrengthen the Work or
to ſave Expence, was firſt invented by the
Carpenters, and afterwards imitated by the
Maſons, who thereby gave no ſmall Beauty to
their Structures. Any of theſe Apertures would
be more beautiful if their Ribs were all of one
Piece, made of one entire Stone; and next to
this, is the having the Parts ſo nicely joined
that the Joints cannot be ſeen. The Ancients
uſed to erect their Columns and other Stones
which ſerved as Ribs to theſe falſe Apertures,
and fix them firm on their Baſes, before they
carried up the Wall; and herein they did very
wiſely; for by this Means they had more Room
to uſe their Engines, and could take the Per
pendicular more exactly. You may plant your
Column perpendicular upon its Baſe in the fol
lowing Manner: In the Baſe and at the Top
and Bottom of the Column mark the exact
Center of each Circle. Into the Center of the
Baſe faſten an iron Pin, ſoddering it in with
Lead, and make a Hole in the Center of the
Bottom of the Column, juſt big enough to re
ceive the Pin which ſticks up in the Center of
the Baſe. In the Top of your Engine, or
Scaffolding, make a Mark exactly perpendicu
lar over the Pin which ſticks up in the Center
of the Baſe, which you may find by letting ſall
Line from thence to that Pin. When you
have thus prepared every Thing, it will be no
hard Matter to move the Head of the Shaft
till its Center anſwers exactly to the Mark
which you have made above and is perpendi
cular to the Center of its Baſe. I have obſerv
ed from the Works of the Ancients that the
ſofter Sort of Marble may be ſmoothed with
the very ſame Inſtruments with which we
plane Wood. The Ancients alſo uſed to ſet
up their Stones quite rough, only ſmoothing
the Heads and Sides of them which were to
join to other Stones, and aſterwards when the
Building was raiſed, they poliſhed the Faces of
the Stones, which they had leſt rough before;
and this I believe they did that they might
leave the leaſt Expence that was poſſible to the
Hazards of their Engines: For it would have
been a much greater Loſs to them, if by Acci
dent any Stone that was quite ſmoothed and
poliſhed had been let fall and broke, than if