An interesting book

As I was looking for bridge structure for olot on another forum when I found that book.

It the must of the railways technology at the end of the 1920's, a good look on the french signal of that time as well and more.

http://books.google.fr/books?id=ukxLAAAAMAAJ&pg=PA1022&dq=construction+metal+bridge&lr=&num=20&as_brr=1&cd=27#v=onepage&q=construction%20metal%20bridge&f=false


You could download the PDF as well.