PREFACE TO SECOND EDITION 



SINCE the first edition of this work appeared, a great deal of work has 

 been done on the experimental side of Hydraulics, and as far as possible 

 such work has been noted in the present edition. 



The book has been practically rewritten. Much of the original matter 

 has been re-arranged ; some has been deleted ; and considerable additions 

 have been made to almost every section, particularly to those dealing 

 with flow over weirs, through pipes, and in open channels ; with methods 

 of gauging such flows ; and with the mechanical applications of Hydraulics. 

 A chapter dealing with wave motion has been added, as have articles 

 dealing, among other subjects, with the flow of fluids other than water, 

 the admixture of fluids in pipes, and the interaction of passing vessels. 



Such errors as have been noticed in the first edition have been 

 corrected, and the Author would thank those readers whose kindness and 

 courtesy in intimating these, has made their elimination largely possible. 



A. H. GIBSON. 

 DUNDEE, 



October, 1912 



