Pocketbook of Useful Formulæ and Memoranda
for Civil and Mechanical Engineers

PREFACE TO THE SEVENTEENTH EDITION. The Prefaces to the First and Seventh Editions set forth the principles, on which the ‘ Pocket- Book ’ was originally projected, and afterwards received such additions as might be suggested irom time to time—by the Author’s progressive experience, by friendly professional criticism,* and by the advance of engineering science. It is obvious that these “ bit by bit” insertions of fresh matter could not always take the form and place, most convenient for that easy and prompt reference, which this Manual was spe- cially intended to supply. To meet this re- * These friendly criticisms have been thank- fully received, and it is to be hoped will be con- tinued as occasion may require; they may be addressed to the Author at the Publishers’, Messrs. E. and F. N. Spon, Charing Cross.