CHAPTER X¹

THE ARCH LINE

§ 1. WE have seen in the last section how our means of vertical support may, for the sake of economy both of space and material, be gathered into piers or shafts, and directed to the sustaining of particular points. The next question is how to connect these points or tops of shafts with each other, so as to be able to lay on them a continuous roof. This the reader, as before, is to favour me by finding out for himself, under these following conditions.

Let s, s, Fig. 29 (on next page), be two shafts, with their capitals ready prepared for their work: and a, b, b, and c, c, c, be six stones of different sizes, one very long and large, and

¹ [Mr. John Morley, in a lecture on the “Study of Literature,” has commended the plan adopted by Gibbon and some other great men of “always before reading a book, making a short, rough analysis of the questions which they expected to be answered in it.” The plan may be applied also to the writing of books. Thus, in the case of this chapter, it appears, from a sheet of the MS., that Ruskin, before writing it, set himself a kind of examination paper in the subject to be discussed; thus:-

“Describe the principal forms of arches, and the services to which each are adopted.

“An intelligent answer should describe the use of low arches for bridges and strengthening walls; of round arches for vaults, etc.; of pointed arches for height; and of baseless arches in decoration work, as rose-windows, etc.

“What do you consider the best mode of arranging bricks or stones for the lintel of a square aperture? Can you suggest any advisable connection of decorative type with the structural arrangements you prefer?

“Describe the relation of decoration to construction in the principal forms of spires. If you remember the forms used at Salisbury, St. Pierre of Caen, and Freiburg in Breisgau, take these for illustrations of your answers.

“Describe the best known constructions of stone staircases. Which would you consider most generally advisable in modern buildings?

“Can you suggest any more...”

But here the examination paper, which (it will be seen) had begun to range over a wide field, was broken off, and the MS. continues with the beginning of ch. x. as in the text.]

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[Version 0.04: March 2008]