_Of Things that are Common to several Orders._
Before we treat of the Differences of these Five Orders, it would be
proper to speak of those Things that are common to several Orders; as
are the _Steps_, _Pedestals_, the _Diminution of Pillars_, their
_Channelling_, _Piedements_, _Cornices_, and _Acroteres_.
[Sidenote: _Lib. 3. Chap. 3._]
The _Steps_ which are before the Temple, ought always to be of an
unequal Number, to the end, that having put the right Foot in mounting
the first _Step_, it may likewise be upon the last.
They ought not to be more than 6 Inches 10 Lines high, nor less than 6
Inches.
[Sidenote: _Lib. 9. Chap. 2._]
Their breadth ought to be proportion'd to their height, and this
Proportion ought to be of 3 to 4; so that if the _Steps_ be 6 parts
high, which is 3 times 2, they must be 8 broad, which is 4 times 2;
following the Proportion of a Triangular Rectangle invented by
_Pythagoras_.
[Sidenote: _Lib. 3. Chap. 3._]
The Landing-places ought not to be narrower than 16 Inches and an half,
nor broader than 22 Inches, and all the _Steps_ that are round about a
Fabrick should be all of the same breadth.
The _Pedestals_ which support many Pillars of the same Rank, will be
much handsomer if one make them jet out before every Pillar like a
Joynt-Stool; for otherwise, if the _Bases_ were all of one size, they
would resemble a Channel.
If Leaning-places, or Elbow-places are to be betwixt the _Pedestals_,
it's necessary that they be as high as the _Pedestals_, and that the
_Cornices_ of the _Pedestals_, and of the Leaning or Elbow-places be
equal, and have a true Proportion one to another.
[Sidenote: _Lib._ 5. _Chap._ 1.]
[Sidenote: _Lib._ 3. _Chap._ 2.]
All the Pillars ought to go diminishing towards the top, to augment
their Strength, and render them more Beautiful, imitating the Bodies of
Trees, which are greater at the Bottom than at the Top. But this
_Diminution_ must be lesser in the great Pillars which have their
highest part further from the Sight, and which by Consequence makes them
at the top seem lesser, according to the ordinary Effect of Perspective;
which always diminisheth Objects according to the measure that they are
distant from the Eye.
The Rule of this different _Diminution_ is, that a Pillar that is 15
Foot high, ought to have in the upper part 5 parts of 6 in the which the
Diameter of the _Base_ of the Pillar is divided; that which is from 15
to 20 Foot, ought to have 5 and an half of the 6 and an half of the
Diameter; that which is from 20 to 30, ought to have 6 of the 7 parts of
the Diameter; that which is from 30 to 40, must have 6 and an half of 7
and an half of the Diameter; that which is from 40 to 50, must have 7
of 8 of the Diameter. These _Diminutions_ do not belong to the _Thuscan
Order_, whose Pillars are much more diminished; as we shall show
hereafter.
[Sidenote: _Lib. 3. Chap. 3._]
Besides this _Diminution_ which is made towards the top of the Pillar,
there is another below, which makes the Pillar about the middle swell
like a Belly; the measure of this swelling is taken from the magnitude
which makes up the Distance between the _Channels_.
[Sidenote: _Lib. 3. Chap. 2._]
There is another sort of _Diminution of Pillars_, which is made of one
Pillar in respect of another; It is of 2 sorts, _viz._ when a second
rank is placed upon the first, for then the second Pillar must be lesser
a fourth part than those below, or when _Portico's_ are made that have
Pillars in the Corners, for those in the middle must be less than those
in the Corners, a 50th part.
[Sidenote: _Lib. 4. Chap. 1._]
The _Channellings_ are so called, because they are as it were
_Demi-Channels_, which descend from the top of the Pillar to the bottom;
they represented the Plaites of the Garments of Women, which the Pillars
resembled.
[Sidenote: _Lib. 4. Chap. 3._]
There are three sorts of _Channellings_, the two first are particular
and proper to the _Dorick Order_; the third is common to the _Ionick_,
_Corinthian_ and _Compound_: The two first are more plain and simple,
and fewer in number than the others.
The most Simple is that which is not hollowed at all, and which hath
only _Pans_ and flat Fronts or Faces.
[Sidenote: _Lib. 3. Chap. 3._]
The other is a little hollowed; to make this hollowness, a Square must
be made, whose Side must be equal to the _Pan_, in which the
_Channelling_ is to be made, and having put one foot of the Compass in
the middle of the Square, make a crooked Line from one Angle of the
_Channelling_ to the other, both these _Channellings_ are made up to the
number of Twenty.
[Sidenote: _Lib. 4. Chap. 1._]
[Sidenote: _Lib. 4. Chap. 4._]
The other Orders have 24, and sometimes 32, when it is design'd to make
the Pillars seem greater than they are; for the Eye judgeth that all
things are greater when they have more and different Marks, which lead
as it were the Sight to more Objects at once.
These _Channellings_ are deeper than those of the _Dorick Order_, and
the depth ought to be just so much, that a Carpenter's Rule being put
into the Cavity, touch with its Angle the bottom, and with its sides the
two Corners of the _Channelling_. _Vitruvius_ hath not taught us what
the Proportions of the _Channelling_ should be, in respect of the
_Fillet_ which makes up the space between the _Channellings_, nor what
the breadth of the _Fillet_ should be, which he hath establish'd for the
rule of the swelling Belly of the Pillar.
The _Piedement_ is composed of a _Tympan_ and _Cornices_; to have the
true height of the _Tympan_, we must divide the breadth which is between
the two ends of the _Cymatium_ of the _Larmier_, or _Drip_ which
supports the _Piedement_, into 9 parts, and give one to the _Tympan_.
The thickness of the _Cornice_ being added to this 9th part, makes up
the height of the whole _Piedement_ or _Fronton_.
The _Tympan_ ought to be Perpendicular upon the _Gorge_ of the Pillar,
the things that are common to all _Cornices_ are, that the _Cornice_ of
the _Piedement_ must be equal to that below, excepting the last great
_Cymatium_, which ought not to be upon the _Cornice_ below the
_Piedement_, but it ought to go over the _Cornices_ which are sloping
upon the _Piedement_ or _Fronton_.
This great _Cymatium_ ought to have of height an 8th part more than the
_Crown_, or _Drip_, or _Larmier_.
In places where there are no _Piedements_, in the great _Cymatiums_ of
the _Cornices_, must be cut the Heads of Lions, at such a distance, that
there must be one directly upon every Pillar, and that the other answer
directly upon the great _Dalles_, that cover the House. These Heads of
Lions are pierced through to convey the Water which falls from the Roof
upon the _Cornice_: The Heads of the Lions which are not directly upon
the Pillars, ought not to be pierced, to the end the Water may flow with
the greater impetuosity through those which are directly upon the
Pillars, and that it may not fall between the Pillars upon those who are
to go into the _Portico's_.
The _Greeks_ in their great Buildings never put any _Dentels_ under the
_Modillons_, because the _Rafters_ could not be under the _Forces_, or
_Sheers_, and it is a great fault that That, which according to the true
Rules of Building ought to be placed above, should be placed under in
the Representation.
For this Reason, the Ancients never approved of _Modillons_ in the
_Piedements_, nor of _Dentels_, but only simple _Cornices_; for neither
the _Forces_, _Sheers_, nor the _Rafters_ can be represented in the
_Piedements_, out of which they cannot jet but only directly out of the
Eaves of the House upon which they lie sloping.
The _Acroteres_ are three _Pedestals_, which are upon the Corners and
Middle of the _Piedement_ to support Statues; those of the Corner ought
to be as high as the Middle of the _Tympan_; but the _Acrotere_ in the
middle ought to be higher by an 8th part than the other.
All the Members or Parts which shall be placed upon the Capitals of
Pillars, _viz. Architraves_, _Frises_, _Cornices_, _Tympans_, and
_Acroteres_, should encline forward the 12th part of their height.
There is likewise another General Rule; which is, that all the parts
that jet out, should have their Projecture equal to their Height.