MEDIAEVAL PAVEMENT AND WALL TILES OF DERBYSHIRE. I 27 



and 10, F. To judge from existing pavements, these squares 

 were not usually repeated so as to form large diapers, but were 

 used as panels on a ground of plain tiles, or to fill in the inter- 

 stices of a trellis of the same. In the next group are tiles or sets 

 of tiles bearing devices decoratively incomplete, through the 

 introduction of some detail that is only completed when two or 

 more of these tiles or sets of tiles are brought together. As a 

 simple illustration, take No. 2, plate F. There we have a quarter 

 circle in each angle of the tile : if of a series of this tile we make 

 a diaper, the quarter circles of each will so unite with those of its 

 neighbours as to form circles. Other more elaborate connecting 

 links, as flowers, radiating foliage, and crosses, were also used, 

 examples of which may be seen in Nos. 7, 16, plate E, and 5, F. 



So far, combination can only produce a pattern of independent 

 units— in the earher mentioned groups, a simple repetition of the 

 same form ; in the last, the more pleasing alternation of a greater 

 contrasted with a smaller. In the next groups, the main pattern 

 is continuous or interlacing, and independent forms play only a 

 subordinate role. A common framework is the lattice. No. 7, 

 plate E, is a good example to the point. In this, it will be 

 noticed that in combination, the bars of the lattice will intersect at 

 the sides across the joints ; sometimes they do so at the centres 

 and angles instead. More frequently, the pattern consists of 

 intersecting circles. The amount of their overlays varies, but it 

 usually was such as to divide the periphery of each circle into 

 four vesicas. The pattern can easily be made : all that is neces- 

 sary is to cover a flat surface with circles rectangularly arranged 

 and touching one another, and then from the centres of the 

 quadrilateral interspaces, to describe another series of the same 

 size. The result will be as above, a series of vesicas with inter- 

 vening quadrilateral spaces. Although seemingly so different, 

 Nos. 8, 10, 17, plate A ; 2, plate C ; and 2,i\, F, will, all in com- 

 bination, produce this pattern. Now reduplicate the pattern by 

 striking similar circles from every point of intersection, the result 

 will be that every vesica is crossed at a right angle by another, 

 as in No. 12, plate A. No. 14, plate /^, is a good example of 



