A building may be divided into three primary parts, a substructure or base, the supporting members and the supported part. When the supporting member is continuous it is called a wall, if however, the supported part is carried upon heavy, more or less isolated supports, these are called piers. The lighter, more slender supports are called columns. The member which rests upon the columns or piers, spanning the space between them and carrying the parts above, is a beam or lintel, and when the lintel is the direct support for a roof, it, together with the overhanging part of the roof, is called an entablature. The wall in a pediment is known as the tympanum.
Plates 62 to 73
That ornamented columns were made use of many centuries before Christ has been proven by the discoveries of archaeologists. The form and proportions of these supports were gradually improved until, in the classic temples, they reached the height of their development.
Many examples of these classic columns are in existence today together with their entablatures, bases, etc. These have been measured carefully and drawn up, making them available to the designer.
The classic column consists of a shaft which is ornamented at the top by a capital and at the bottom by a base. The base is sometimes carried upon a member called a pedestal when short and a podium when continuous. The column together with its entablature identify the style of architecture of the building and is called an Order of Architecture.
The diagram on Plate 62 gives the names of the various parts of the classic Orders for reference as they are used in the following text.
There are many and various examples of each of the Orders. Those given in the accompanying plates seem best to represent each Order.
Plate 62 gives a comparison of the proportions of the five Orders of Architecture as fixed by the Italian architect, Giacomo Barozzi, born at Vignola, Italy, in 1507, died 1573. The Greek Order of the Parthenon at Athens and the Egyptian Order of the Temple of Karnak are also shown.
All dimensions on the plates are given in terms of the base diameter of the shaft. This diameter is divided for convenience into two parts called modules and each module is divided into 30 equal divisions called parts.
In studying the Orders, the student should learn their principal proportions and rely on the plates only for those detailed dimensions which can not be called to mind readily. After becoming acquainted with the Orders and with the principles of design, it will be found that the details may be varied almost at will, to suit conditions.
Vignola's TUSCAN ORDER
The Tuscan is a Roman Order named from Tuscany, a part of Italy. It is really a simple Roman Doric being very similar to that Order except that it has no ornament and lacks the refinement of the other Roman Orders. The proportions seem to be those peculiar to timber construction rather than stone.
There are very few fragments of this Order remaining to us but several of the Italian masters have invented what they thought should be the details and dimensions of the complete Order. The best of these is probably the one invented by Vignola and is given on the opposite Plate 63. It is very simple and easily executed, all of the moulding profiles being made up of circle arcs and straight lines. The column shaft is not fluted and the base consists of a simple torus resting upon a perfectly plain plinth block.
The Doric Order was probably named after the race of Dorians, a people of ancient Greece. It is the oldest of the three Greek Orders and in it is found the most subtle refinement of outline and proportion known to architecture. It is said that the proportions of man were the basis of the Doric dimensions, a man being about six times as high as the length of his foot, so the column height is about six times its base diameter.
The best example of this Order is that of the Parthenon at Athens, built about 438 B.C. The Order of the Parthenon is given on Plate 64.
The base of the Greek temple is called a stylobate and usually consisted of three large steps. The Doric column has no base, the shaft rising directly from the stylobate and having a height from 4 1/4 to 6 1/2 times its base diameter. The column usually was scored with 20 elliptical channels meeting in a sharp edge or arris. The capital is very simple and suggests great supporting strength. It consists of a heavy square slab called an abacus below which is an ovolo echinus of subtle profile. Toward the bottom of the echinus are several raised bands or annulets against the lower one of which the channels terminate. There is no distinct necking to this order, but in place of an astragal we find grooves on the shaft just below the echinus. These are called scanilli. They produce a pleasing band of shading at this point. The shaft between the annulets and the scamilli is called the hypolrachcliuni.
Most of the Greek Doric architraves are plain and very deep, and the soffits are a little less than two modules in width in the better examples. At the top of the architrave is a broad terminating fillet called the taenia, also a flat band called a regula from which are suspended the peg-like forms called guttae occurring beneath each triglyph.
PLATE 64. GREEK DORIC ORDER OF THE PARTHENON AT ATHENS
The frieze contains a series of raised slabs called triglyphs, between which are square spaces called metopes. A triglyph occurs over the center line of each column and one centered over the space between columns. Thus the width of the metope determines the spacing of the columns. Where there is a break in the entablature as at the corner of the building the triglyph occurs at the corner and not centering over the corner column. The next triglyph then is centered between the corner one and that over the next column which makes the metopes between them slightly wider than normal. As the corner columns are usually placed closer together than the others, this difference in the metopes is not noticeable. The triglyphs are about one module in width and are scored with two vertical V shaped channels and the two corners are chamfered with a cut similar to a half channel. These channels begin down on the cap of the architrave and terminate in slightly varying forms just below the plain band cap of the triglyph. The face of the triglyph usually lines up with that of the architrave below, while the face of the metope is set back and usually ornamented with sculptured and painted figures. There is a plain band cap on the metope similar to that of the triglyph but not quite so wide. The corona projects about one module beyond the frieze and is about three-fourths as high as its projection. Its lower surface or soffit slopes up toward the building to a broad continuous band just above the frieze. The soffit is broken up by flat blocks called mutules, one occurring over each triglyph and each metope. On the lower surface of the mutules are guttae similar to those on the architrave. The crowning member of the entablature is the cymatium which is often richly ornamented.