The variety of articles used by the engineer and builder - which are made from burnt or baked clay - is endless.
A few of the more important may now be mentioned.
Damp-proof Courses are made in stoneware (or sometimes in fireclay) pierced with perforations of different patterns.
A damp-proof course slab in stoneware, as made by Messrs. Doulton, with ribbed surfaces and tongue and groove joints, is shown in Fig. 58. A thicker slab, as made by Mr. Jennings, is shown in Fig. 59. The method in which these damp-proof courses are used is explained at page 216, Part II.