§ IV. There is not much variety in the case of the first, _a_, Fig. XLVIII. In the Cumberland and border cottages the door is generally protected by two pieces of slate arranged in a gable, giving the purest possible type of the first form. In elaborate architecture such a projection hardly ever occurs, and in large architecture cannot with safety occur, without brackets; but by cutting away the greater part of the projection, we shall arrive at the idea of a plain gabled cornice, of which a perfect example will be found in Plate VII. of the folio series. With this first complete form we may associate the rude, single, projecting, penthouse roof; imperfect, because either it must be level and the water lodge lazily upon it, or throw off the drip upon the persons entering.
§ V. 2. _b_, Fig. XLVIII. This is a most beautiful and natural type, and is found in all good architecture, from the highest to the most humble: it is a frequent form of cottage door, more especially when carried on spurs, being of peculiarly easy construction in wood: as applied to large architecture, it can evidently be built, in its boldest and simplest form, either of wood only, or on a scale which will admit of its sides being each a single slab of stone. If so large as to require jointed masonry, the gabled sides will evidently require support, and an arch must be thrown across under them, as in Fig. XLIX., from Fiesole.
If we cut the projection gradually down, we arrive at the common Gothic gable dripstone carried on small brackets, carved into bosses, heads, or some other ornamental form; the sub-arch in such case being useless, is removed or coincides with the arch head of the aperture.
§ VI. 3. _c_, Fig. XLVIII. Substituting walls or pillars for the brackets, we may carry the projection as far out as we choose, and form the perfect porch, either of the cottage or village church, or of the cathedral. As we enlarge the structure, however, certain modifications of form become necessary, owing to the increased boldness of the required supporting arch. For, as the lower end of the gabled roof and of the arch cannot coincide, we have necessarily above the shafts one of the two forms _a_ or _b_, in Fig. L., of which the latter is clearly the best, requiring less masonry and shorter roofing; and when the arch becomes so large as to cause a heavy lateral thrust, it may become necessary to provide for its farther safety by pinnacles, _c_.