On Architecture

Vitruvius Pollio

Vitruvius Pollio, creator; Morgan, M. H. (Morris Hicky), 1859-1910, translator

4. Upon the columns lay the main beams, fastened together, to a height commensurate with the requirements of the size of the building. These beams fastened together should be laid so as to be equivalent in thickness to the necking at the top of a column, and should be fastened together by means of dowels and dove-tailed tenons in such a way that there shall be a space two fingers broad between them at the fastening. For if they touch one another, and so do not leave airholes and admit draughts of air to blow between them, they get heated and soon begin to rot.

5. Above the beams and walls let the mutules project to a distance equal to one quarter of the height of a column; along the front of them nail casings; above, build the tympanum of the pediment either in masonry or in wood. The pediment with its ridgepole, principal rafters, and purlines are to be built in such a way that the eaves shall be equivalent to one third of the completed roof.

1. THERE are also circular temples, some of which are constructed in monopteral form, surrounded by columns but without

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a cella, while others are termed peripteral. Those that are without a cella have a raised platform and a flight of steps leading to it, one third of the diameter of the temple. The columns upon the stylobates are constructed of a height equivalent to the diameter taken between the outer edges of the stylobate walls, and of a thickness equivalent to one tenth of their height including the capitals and bases. The architrave has the height of one half of the thickness of a column. The frieze and the other parts placed above it are such as I have described in the third [*](Codd. quarto) book, on the subject of symmetrical proportions.

2. But if such a temple is to be constructed in peripteral form, let two steps and then the stylobate be constructed below. Next, let the cella wall be set up, recessed within the stylobate about one fifth of the breadth thereof, and let a place for folding doors be left in the middle to afford entrance. This cella, excluding its walls and the passage round the outside, should have a diameter Let

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the columns round the cella be arranged in the symmetrical proportions just given.

3. The proportions of the roof in the centre should be such that the height of the rotunda, excluding the finial, is equivalent to one half the diameter of the whole work. The finial, excluding its pyramidal base, should have the dimensions of the capital of a column. All the rest must be built in the symmetrical proportions described above.