^NATURE'S TEACHINGS:' 97 



cable, the anchor, and the boat-hook are all to be 

 found typified in Nature, together with almost every 

 other appliance which man employs for navigation in 

 its widest sense. Part II. treats of War and Hunt- 

 ing, and shows the analogy between the offensive 

 and defensive weapons of man, civilised and un- 

 civilised, with those in the possession of animals 

 which existed in the world long before him. The 

 pitfall, the sword, the spear, the net, the "gin,'' the 

 hook, and even the blow-gun, all are shown typically 

 to be in the possession of divers animals, although 

 for the most part invented independently by man. 

 Then follow in turn sections appropriated to archi- 

 tecture, tools, optics, and useful arts, and the book 

 closes with a chapter on Acoustics, in which is shown 

 the analogy existing between the vibration of a violin- 

 string and that of the notched ridge upon the wing- 

 case of a cricket ; between the trombone and the 

 throat of the swan ; and between our " whispering 

 galleries " and the natural echo. 



The subject had always been a very favourite one 

 with my father, and he was never tired of working 

 it out, and showing its manifold applications. He 

 refers to it in several of bis books ; he devoted to it 

 many a magazine article ; and few of those who 

 ever attended his sketch-lectures will fail to recollect 

 how frequently he brought the same subject forward, 

 and how he delighted in showing, for instance, the 

 similarity between our life-boats and the egg-boat 

 of the gnat; always with the remark that in this, 



