An Abridgment of the Architecture of Vitruvius

Lib. 6.

Chap. 11. THE Foundation is the most important part of the Fabrick; for the Faults committed in it cannot be so easily remedied as in other parts.

To lay the Foundation well, you Lib. 1.

Chap. 5. must dig till you come to solid Ground, and even into the solid as much as is necessary to support the Weight of the Walls; it must be larger below than above the Superficies of the Earth.

Lib. 3.

Chap. 3. When you have found firm Earth to make it more solid, you must beat it with a Rammer; but if you cannot arrive at solid Earth, but find it still soft and spungy, you must dig as far as you can, and drive in Piles of Alder, Olive, or Oak, a little singed, near together, and fill up the void Places between the Piles with Coal.

Lib. 1.

Chap. 5. In short, you must make all Masonry with the most solid Stone that can be found for this use.

To make the Binding of the Stones the stronger in the Foundation of great Fabricks, you must put Piles of Olive a little singed and placed very thick from one Parement or Course to another, which serves, as it were, for Keys and Braces; for this Wood so prepar'd, is not subject to Worms, and will endure for ever, either in the Earth or in the Water, without the least Damage.

Lib. 6.

Chap. 11. When you would make Cellars, the Foundations must be much larger; for the Wall that is to support the Earth requires a greater thickness to resist the strong Efforts that the Earth makes against it in Winter, at which time it swells and becomes more heavy by reason of the Water it has drunk up.

ART. IV

Of the Walls

Lib. 4.

Chap. 2. THE right ordering of Stones joined with Mortar, which is call'd Masonry, is sevenfold; there are three of them which are of hewed Stone; viz. that which is in Form of a Net, that which is in Binding, that which is call'd the Greek Masonry. There are likewise three sorts of Masonry of unhewed Stones; viz. that which is of an equal Course; and that which is of an unequal, and that which is fill'd up in the middle; the seventh is compounded of all the rest.

The Net-Masonry is that which is made of Stones perfectly squar'd in their Courses, and are laid so, that the Joints go obliquely, and the Diagonals are the one Perpendicular, and the other Level. This is the most pleasing Masonry to the Sight, but it is apt to crack. See the Figure A. Table I.

The Masonry call'd the Bound-Masonry, is that, as Vitruvius explains it, in which the Stones are plac'd one upon another like Tiles; that is to say, where the Joints of the Beds are Level, and the Mounters are Perpendicular; so that the Joint that mounts and separates two Stones falls directly upon the middle of the Stone which is below.

Some Authors call this sort of Masonry Incertain, but they are mistaken; for they read Incerta instead of Inserta; it is not so Beautiful as the Net-work, but it is more solid and durable. See the Figure BB. Table I.

The Masonry which Vitruvius says is particular to the Greeks, is that, where after we have laid two Stones, each of which make a Parement or Course, another is laid at the end, which makes two Parements or Courses, and all the Building through observe this Order. This may be call'd Double-Binding; for the Binding is not only of Stones of the same Course one with another, but likewise of one Course with another Course. See Figure CC. Table I.

The manner of Walling by unequal Courses call'd Isodomum by the Ancients, differs in nothing from the Masonry call'd Bound-Masonry, but only in this, that the Stones are not hewed. See Figure D. Table I.

The other manner by unequal Courses call'd Pseudisodomum is also made of unhewed Stone, and laid in Bound-Work, but they are not of the same thickness, and there is no equality observ'd, but only in the several Courses, the Courses themselves being unequal one to another. See Figure A. Table I.

The Masonry which is fill'd up in the middle, call'd by the Ancients Emplecton, is likewise made of unhewed Stone and by Courses, but the Stones are only set in order as to the Parements or Courses, but the middle is fill'd up with Stones thrown in carelesly among the Mortar. See Fig. FF, GG, H. Table I.

Among all these sorts of Masonry, that will always be best which is made of Stones of an indifferent size, rather lesser than greater; to the end that the Mortar penetrating them in more parts may bind them faster, and the strength of the Mortar does not so soon decay. For we see that the Mortar which is laid in the Joints or Seams of the greater Stones with time decays and turns to Dust, which never happens to the most Ancient Fabricks which have been built of little Stones. From thence we may conclude, that it is ill Husbandry to be sparing of Mortar.

For this reason Vitruvius proposes another sort of Masonry, which may be call'd the Compound Masonry, for it is all the former together, of Stones hewed and unhewed, and fastned together with Cramp-Irons. The Structure is as follows: The Courses being made of hew'd Stone, the middle place which was left void is fill'd up with Mortar and Pebbles thrown in together; after this they bind the Stones of one Parement or Course to those of another with Cramp-Irons fasten'd with melted Lead. This is done to the end, that the abundance of Mortar which is in the middle may furnish and communicate a sufficient Humidity to the Joints of the great Stones which make the Parements. See the Figure K. Table I.

There are many Precautions to be given to make the Masonry more firm and durable, and these Precautions are common to all the different sorts of Masonry.

Lib. 1.

Chap. 5. When you would have the Walls very thick, for great and heavy Buildings, you must strengthen the inner part of the Wall with long Piles of singed Olive, which serves for Keys and Braces, for this Wood being so prepar'd never corrupts.

Lib. 6.

Chap. 11.

Vide Index. It is likewise of great Importance for the strength of Walls, that all be directly Perpendicular, and that the Chains, the Pillars and Pieds-droits or Piers be so situated, that solid always answer'd to the solid; for if there be any part of the Wall or any Pillar that carrys false, it is impossible the Work should continue long.

There are also two ways of strengthning the Walls, which are either to ease them of their own weight, or of that of the Earth which they are to support.

The first way of easing is in those Places where there are void spaces, as above Doors or Windows. These easements may be made two different ways; the first is to put over the Lintel which supports the Wall, which is over the void space of the Gates and Windows, two Beams, which lying or resting below directly upon Pieds-droits or Piers meet together above.

The other way is, to make directly over the void spaces Vaulted Arches with Stones cut corner-ways and tending to one Center. For the Walls be so strengthned by the means of these easements, that part of the Wall which is below will not sink at all being easied of the load of the part that is above, and if some defect should happen by tract of time, it may be mended without propping that which is above.

The second way of easing, is, for Walls that are made to support the Earth; for, besides the extraordinary thickness which they ought to have, they should have likewise Buttresses on that side next the Earth, so far distant one from another as is the breadth of the Wall; they ought likewise to have an Emparement or large Foundation which must be equal to the height of the Wall, so that they go diminishing by degrees from the bottom to the top, where they come to equal the height of the Wall.

Lib. 1.

Chap. 5. The effect of these Buttresses is not only to support the Earth by their Resistance, but likewise to lessen its Efforts when it swells, in dividing it into many parts.

Lib. 6.

Chap. 11. And it be judg'd that these Buttresses be not sufficient, the Wall also which supports the Earth must be strengthned with other Buttresses within.

ART. V

Of Flooring and Ceiling

THere are four sorts of Flooring, some are upon the Superficies of the Ground, others between two Stories, others make the Roof of the House in Plat-form, and the last is Plat-Fond.

To make those Floors that are upon the Ground, you must first make the Earth smooth and plain, if it be firm and solid, if not, it must be beaten with a Rammer with which they ram down their Piles; and after having cover'd the Earth with the first Lay or Bed, call'd Statumen by the Ancients, which was of Flinty Stones about the bigness of ones Fist, among which was mixed Mortar made of Lime and Sand. Then they laid the second Bed, which they call'd Rudus, which was made of lesser Stones, of which there were three Parts for one of Stone if they were new, for if they were taken out of old Buildings, five parts of Stones or Pibbles would be required for two of Lime.

The Greeks had a way of making their Lib. 7.

Cap. 4. Floors in those low places where cold and humidity ordinarily reign, which freed them from these Inconveniences. They digged the Earth two Foot deep, and after having beaten it well, they laid a Bed of Mortar or Cement a little sloping from either side to the Channel, which convey'd the Water under Ground; they laid a Bed of Coal upon the first Mortar, and having beaten them well, they cover'd them with another Cement or Mortar made of Lime, Sand and Ashes, which they made smooth when it was dry with a Polishing-Stone. These Floors presently drank up the Water that fell upon them, that one might walk barefoot without being incommoded by the Cold.

For the Floors which are between two Stories, there must be a particular care taken, that if there be any Partition below it, that it may not touch the Flooring for fear lest if the Flooring came to sink a little, it might be broke upon the Partition which remains firm.

To make these Floorings, the Boards must be nailed at each end upon every Joist, to the end they may not warp; these Boards or Planks being cover'd with Straw, to hinder the Lime from wasting the Timber, the first Bed must be laid, made of a mixture of Mortar and little Stones a hand breadth, which must be beaten a long time with Iron-Levers, and so it must make a solid Crust which must be nine Inches thick; upon it shall be laid the Noyau or Ame, which must be at least six inches thick: It must be made of Cement, with which must be mix'd one part Lime for two parts Lib. 7.

Cap. 4. of Cement. Upon the Ame or Noyau is placed the Parement made with the Rule, afterwards it must be scrap'd and all the Eminences and Inequality taken away: After that must be laid a Composition of Lime, Sand and beaten Marble, to fill equally all the Seams or Joints.

If a Flooring be to be made in the open Air, as upon Terrasses, that may endure Rain or Frost without any Damage; you must nail upon the Joists two Ranks of Boards across, one above the other; and having laid the first Bed, as is said before, it must be Paved with great Square Bricks two Foot Square, which must be hollow'd in the Ends in the Form of a half-Channel, the breadth of an Inch, which must be fill'd with Lime mixed with Oil. These Square Bricks must be higher in the middle, sloping two Inches for every six Foot; that is to say, a Forty-eighth Part. Upon these Square Bricks must be laid the Ame; upon which, after it has been well beaten, as well as the rest, must be put great Square Stones; and to hinder the Moisture from hurting the Boards, it is good to pour as much of the Lees of Oil as they will soak up.

The under part of the Flooring, and the Plat-Fonds, must be made also with great Care. To make the Plat-Fonds or Flat-roofs, in the Form of a Vault, you must nail to the Joists of the Boards, or to the Lib. 5.

Chap. 10. Rafters of the Roof, from two Foot to two Foot pieces of crooked Timber, and Choice must be made of Timber that is not apt to rot; such as, viz.Cypress, Box, Juniper, and Olive; no Oke must be made use of, because it will warp and crack the Work. The Joists being fastened to the Suntmers, you must fix to them Spanish-Broom with Greek-Reeds well beaten. These Reeds are in stead of Laths, which at present are made use of to make the Eaves of Houses; over these Reeds must be laid a Plaster of Mortar, made of Sand, to hinder the Drops of Water which may fall from above from endamaging these Plat-Fonds. After which, the under part must be Plaster'd pretty thick, making all Places equal with Mortar made of Lime and Sand, that it may be afterwards Polished with Mortar made with Lime and Marble.