Page:History of Art in Primitive Greece - Mycenian Art Vol 2.djvu/194

to understand how, with very simple means, these evils were successfully overcome. We next come to the double architrave a. In order to protect its upper face and assure its steadiness, we will place over it beam c, whose salient rini will meet the grooved edge of pillar D, and prevent its slipping backwards. Having now given a back prop to pillar d, we must see that it does not bend and fall forward. The result can be obtained by the simple use of pegs. In carpentry work, no better means can be devised than wooden pins for joining pieces together. A carpenter who knows his business employs no metal bolt, hook, or nail, but is content to secure his scarf-joints with wooden pegs and straps. Wooden clamps and pegs, moreover, have this advantage over iron bolts : being of the same substance as the elements to which they serve as means of union, atmospheric variations act on both alike ; this would not be the case with a substance of different nature, such as bronze and iron ; pegs prevent both the spreading and tension of the timbers, and their parting and breaking under the pressure of a foreign body. Pegs did well enough as means of attach- ment between the architrave and timber b^; but they were wholly inadequate to hinder warping, twisting, and consequent gaps between the pieces, or to assure the horizontality of the frieze. These serious drawbacks were obviated by a small tablet b, which fitted into the channelled edge of pillar d above the architrave, where it rendered a twofold service to this member of the wood-frame. The greater tailing of the pegs into the thickness of the timber gives them more stability, whilst the number of the small boards would diminish the hydraulic pressure on the woodwork, and help rather than interfere with the play of the wood. Having gone thus far, it only remains to fix the frieze in such a way that it shall stand well. This can be satisfactorily accomplished by uniting the ends of the two pieces, plate f and pillar d, by a scarf joint, so as to form a continuous piece. Now, in the pillars of the Tirynthian frieze, this portion is left plain or with unfinished ornaments ; a clear proof that the part was concealed by a lining f, whose existence we have been led to divine independently. Thus, examination of the alabaster slabs confirms at every point the assumption reached by inductive reasoning and constructional necessities. Fig. 305 shows the