1888 IRON ROOFS Walmisley : London Bridge Station : Lime Street etc Engineering

The demand for a book, which would serve as a guide to the Civil Engineer, in the selection of the best class of Iron Roof, for the covering of a large or small space, where particular requirements have to be met, induced the Author to prepare the first edition of this work. His chief object was simply to provide a record of the style of design adopted in some of the best known roofs that have been erected. The second edition has been considerably enlarged and improved. Metre scales have been added to the Plates, and an Appendix inserted in the letter-press, in which the usual specified tests for material have been investigated, and the calculation of strains in some of the best known forms of roofs considered. The Author trusts that the tabular statement of the principal dimensions of fifty iron roofs on page 36, arranged in the order of their span, may prove useful. Too much importance must not be laid upon the cost quoted for different roofs, as they were erected at different times, and the price of material is constantly varying. Even with a uniform price for iron, comparisons cannot be usefully made, unless every particular is included. The Author has, however, stated the price where possible, as one of the questions which engineers are compelled to enter into, is the financial result of their work. In conclusion, the Author desires to express his gratitude to those Engineers and Contractors who have supplied him with copies of the working drawings from which the several Plates have been photo-lithographed by Messrs. Sprague & Co., and he hopes that the vastness of the subject may be sufficient excuse for the omission of any special roof that the reader might have expected to have found mentioned.