“The Military Classification of Bridges in Great Britain.”^*

AT the time when war broke out no systematic assessment of the

strength of existing road bridges in Great Britain had been made, with the

exception of those in railway ownership and a few other cases of obvious

weakness where Orders restricting loads had been made under the Road

Traffic Acts. The railway companies, in accordance with the requirements

of the Road and Rail Traffic Act, 1933, had calculated the strengths of their

road overbridges according to rules agreed between themselves, and had

scheduled those which were found not strong enough to carry loads greater

than 12 tons. The stresses adopted for that purpose were 21 tons per