The house-blocks divided by these streets were thought to vary somewhat in size but to measure in general about 300 x 330 metres.[28] More recent research, however, has not confirmed Mahmud's plans.

The excavations of Mr.Hogarth and M.Botti suggest that many of his lines are wrong and that even his Canopic Street is incorrectly laid down.

Mr.Hogarth, indeed, concludes that 'it is hopeless now to sift his work; those who would treat the site of Alexandria scientifically must ignore him and start _de novo_'.

More recent excavation, carried out by Dr.Noack in 1898-9, seemed to show that the ancient streets which can now be traced beneath Alexandria belong to a Roman age, though they may of course follow older lines, and that, if some items in Mahmud's plans are possibly right, the errors and omissions are serious.

We may accept as certain the statement that Alexandria was laid out with a rectangular town-plan; we cannot safely assume that Mahmud has given a faithful picture of it.[29] [27] Strabo, xvii.