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.