154 UNSOLVED PROBLEMS. 



than man, or perhaps even his instruments, to feel or hear 

 the very slight shaking motion or rumbling noise that con- 

 stitutes the first symptom of the earthquake. 



There are doubtless many kinds of coming events that can 

 be foreseen and prepared for by such animals as the dog 

 for instance, its master intending to take a walk or to go to 

 church, market, fair, or chase. It may see its master's pre- 

 parations, understand their significance, and make its own 

 arrangements or hold itself ready for orders from its master. 

 And in some of the more puzzling cases above given similar 

 keenness of observation, similar shrewdness in drawing 

 inferences, similar general intelligence, may be the fons et 

 origo of the apparent power of prevision. 



The mode or modes by which the individuals of a species 

 intercommunicate for their common benefit have yet in many 

 cases to be determined. We know a great deal concerning 

 the language of animals, and we have indubitable evidence 

 that they can, and do, constantly communicate to each other 

 intelligence of all kinds warnings of dangers, requests for 

 aid, grievances that have been borne and that require redress, 

 plans of foraging or warlike campaigns, and so forth. But 

 in many cases we are yet ignorant what is the precise nature 

 of the language used, by what means intercommunication 

 is effected. Thus the ' American Whaleman ' (Davis) states 

 that 'sperm whales have a means of communicating with 

 each other at long distances how long has never been de- 

 termined, but certainly at distances .... of six or seven 

 miles. The means are a mystery, but every whaleman has 

 observed the fact, and has based his operations in the chase 

 upon it. It has been suggested that, as water is so good a 

 conductor of sound, it may be sound ; but the distances are 

 too great for any sound which the whale is capable of making 

 to penetrate, and it is observed that the telegraph is as 

 perfect as ever in high winds, when a thousand waves are 

 breaking.' We know just as little, however, of the lan- 

 guage used by dogs to each other for instance, when a 

 small one tells a larger that it has been cruelly used by a 

 bully, whom it cannot itself punish, requesting co-operation 

 in revenge ; or when the pariah dogs of Damascus, as de- 



