It is likely that there were small unevennesses in the ancient as there are in the modern house-blocks.

The 'insulae' which abutted on the town-walls are represented to-day by unduly large blocks, oblong rather than square, but these latter contain not only the areas of the Roman 'insulae' in question, but also the space between them and the town-walls and the lines of the wall themselves (p.

77).
[76] This failure in symmetry recurs in one or two other Roman towns as probably at Timgad (p.

109) and at Cologne (E.and W.
gates), at Silchester and Caerwent, but it may sometimes be the result of alteration.

Occasionally it appears in military sites (Ritterling, _Lager bei Hofheim_, p.