THE 



APPLICATIONS OF PHYSICAL FORCES. 



INTRODUCTION. 

 I. 



IN a former work the Forces of Nature an attempt was made 

 to give a popular account, easy of comprehension to all, of the 

 outlines of those Natural Phenomena known to the scientific world 

 as Gravity, Heat, Light, Magnetism and Electricity. In describing 

 these various phenomena I endeavoured especially to point out 

 some of their most simple and general laws, without having recourse 

 to figures or formulae. The principal object of the Forces of Nature 

 indeed was an exposition of the principles of pure science, with- 

 out reference to the uses which are or can be made of them. The 

 object of the present volume is to conjplete this account of the 

 physical side of Science by describing the most remarkable of its 

 applications, not only in the Arts and Industries, but in the further 

 investigation of Science itself. 



Who now-a-days will deny the influences and importance of the 

 Applications of Science ? Who can deny the ever-increasing part 

 which the practical deductions from scientific theory play in the 

 general progressive movement of modern societies ? Everywhere 

 now we find examples of them, under the most diverse forms, in 

 private and public life, in our dwelling-houses, and in our national 

 edifices. They follow us in the actions of every-day life, our work, 

 our pleasures; they are present with us at the domestic hearth, 

 and in our travels ; they are associated with our joys and our 



