THE DOG. 55 



from our defective knowledge of data upon which 

 to build the brido^e of deductive argument. The 

 reason is there all the time could we but reach it ; 

 and almost daily we are able to account for mys- 

 terious and apparently inexplicable phenomena 

 which utterly baffled our predecessors. 



Probably the manner in which domestic dogs 

 express pleasure is owing to some interlocking 

 of the machinery of cognate ideas. In order to 

 understand this better it may be helpful to con- 

 sider some analogous instances with regard to 

 habits of our own species. 



One of the most philosophical of modern 

 physicians, Dr Lauder Brunton, has clearly and 

 amusingly shown that the instinctive delight 

 and eagerness with which a medical man traces 

 an obscure disease step by step to its primary 

 cause, and then enters into combat with it, is 

 referable to the hunter's joy in pursuit, which 

 doubtless characterised our savage ancestors 

 when they patiently tracked their prey to its 

 lair and slew it for glory or for sustenance. 



Mr Grant Allen, I believe, first suggested that 

 our appreciation of bright and beautiful colours, 

 and therefore of the splendours of the flower- 

 garden or of the sunset tints in the sky, might 



