Very well indeed: he has done already what a number of Greek architects have been thought very clever for having done. But suppose he _cannot_ lift the great stone _a_, or suppose I will not give it to him, but only the two smaller stones at _b_, _b_; he will doubtless try to put them up, tilted against each other, as at _d_. Very awkward this; worse than card-house building. But if he cuts off the corners of the stones, so as to make each of them of the form _e_, they will stand up very securely, as at B. But suppose he cannot lift even these less stones, but can raise those at _c_, _c_, _c_. Then, cutting each of them into the form at _e_, he will doubtless set them up as at _f_. [Illustration: Fig. XXIX.] § II. This last arrangement looks a little dangerous. Is there not a chance of the stone in the middle pushing the others out, or tilting them up and aside, and slipping down itself between them? There is such a chance: and if by somewhat altering the form of the stones, we can diminish this chance, all the better. I must say "we" now, for perhaps I may have to help the reader a little. The danger is, observe, that the midmost stone at _f_ pushes out the side ones: then if we can give the side ones such a shape as that, left to themselves, they would fall heavily forward, they will resist this push _out_ by their weight, exactly in proportion to their own particular inclination or desire to tumble _in_. Take one of them separately, standing up as at _g_; it is just possible it may stand up as it is, like the Tower of Pisa: but we want it to fall forward. Suppose we cut away the parts that are shaded at _h_ and leave it as at _i_, it is very certain it cannot stand alone now, but will fall forward to our entire satisfaction. Farther: the midmost stone at _f_ is likely to be troublesome chiefly by its weight, pushing down between the others; the more we lighten it the better: so we will cut it into exactly the same shape as the side ones, chiselling away the shaded parts, as at _h_. We shall then have all the three stones _k_, _l_, _m_, of the same shape; and now putting them together, we have, at C, what the reader, I doubt not, will perceive at once to be a much more satisfactory arrangement than that at _f_. § III. We have now got three arrangements; in one using only one piece of stone, in the second two, and in the third three. The first arrangement has no particular name, except the "horizontal:" but the single stone (or beam, it may be,) is called a lintel; the second arrangement is called a "Gable;" the third an "Arch."