HYDRAULICS AND ITS 

 APPLICATIONS 



SECTION I. 

 CHAPTEE I. 



Introductory Historical R6sum6 Physical Properties of Water Density Compressibility 

 Cohesion Adhesion Capillarity Surface Tension Viscosity. 



INTRODUCTORY PHYSICAL PROPERTIES OF WATER. 



ART. 1. HYDROMECHANICS. 



THE science which deals with liquids at rest or in motion may be divided 

 into two branches : Hydrostatics, which deals with the equilibrium of 

 liquids at rest ; and Hydrodynamics, which deals with the problems con- 

 nected with their motion. The term Hydraulics is usually broadly applied 

 to that portion of the latter branch which deals with the motion of water 

 in so far as this is of importance in the problems brought directly under 

 the notice of the engineer. 



A knowledge of the fundamentals of Hydrostatics is, however, so essential 

 to a thorough grasp of the principles of Hydrodynamics, and is of such 

 direct importance to the hydraulic engineer, Tihat a treatise on Hydraulics 

 would not be complete without some preliminary treatment of this branch 

 of the subject. 



The origin of the science is of great antiquity, and no attempt will be 

 made to give a detailed historical resumt of its growth. Some few of the 

 principles of Hydrostatics were enunciated by Archimedes (B.C. 250), and 

 it is a remarkable fact that for 1,800 years from this date until the time 

 of Stevinus, Galileo, and Torricelli practically no further progress was 

 made. 



The construction of the elaborate series of aqueducts and of service 

 pipes for supplying Rome with water indeed shows that the Komans 

 possessed some knowledge of the properties of water when at rest and 



H.A. B 



