MENTAL POWERS OF MAN AND LOWEK ANIMALS. 183 



This is no doubt a very important distinction ; but there 

 appears to me much truth in Sir J. Lubbock's suggestion 

 that, when primeyal man first used flint-stones for any 

 purpose, he would have accidentally splintered them, and 

 would then hare used the sharp fragments. From this 

 step it would be a small one to break the flints on pur- 

 pose, and not a very wide step to fashion them rudely. 

 This latter adyance, however, may have taken long ages, 

 if we may judge by the immense interval of time which 

 elapsed before the men of the neolithic period took to 

 grinding and polishing their stone tools. In breaking 

 the flints, as Sir J. Lubbock likewise remarks, sparks 

 would have been emitted, and in grinding them heat 

 would have been evolved ; thus the two usual methods of 

 " obtaining fire may have originated." The nature of fire 

 would have been known in the many volcanic regions 

 where lava occasionally flows through forests. 



THE POWEK OF ABSTEACTIOK. 



If one may judge from various articles 

 which have been published lately, the greatest 

 stress seems to be laid on the supposed entire absence in 

 animals of the power of abstraction, or of forming gen- 

 eral concepts. But when a dog sees another dog at a dis- 

 tance, it is often clear that he perceives that it is a dog in 

 the abstract ; for when he gets nearer his whole manner 

 suddenly changes, if the other dog be a friend. A recent 

 writer remarks that in all such cases it is a pure assump- 

 tion to assert that the mental act is not essentially of the 

 same nature in the animal as in man. If either refers 

 what he perceives with his senses to a mental concept, 

 then so do both. When I say to my terrier, in an eager 

 voice (and I have made the trial many times), "Hi, hi. 



