All the Northerners whose opinions on the subject were recorded agreed tliat the structural design of Milan Cathedral was flawed. In particular, they criticized the buttresses of the outer walls as being too shallow to resist the thrusts from the aisle vaults, vet the Italians were equally adamant that the buttresses were sufficient.

Neither side did more than assert the correctness of their views, and there is no sign that anyone was capable of computing thrusts, even in the rough-and-ready way prescribed in the earliest surviving account of thrusts compiled by a European architect, the tract written c. 1530 by the Spaniard Rodrigo Gil de Hontanon.

In 1400 the Parisian architect Jean Mignot declared that the buttresses at Milan ought to be three times as deep as the piers inside were wide, but lie gave no indication of whether this was an unvarying rule-of-thumb or whether it was his considered estimate of the specific needs of Milan.

The former is the more-likely, since Mignot regarded as absolute errors the many things at Milan which were at variance with the long established practices of the northern French lodges; for him there was no question of making allowances for the difference of milieu.

Literature

1. Cristopher Wilson. The Gothic Cathedral