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become not only lord of the earth, but of the ocean also. 

 Homes says of the ship that it is in the fullest sense both 

 a weapon and a tool ; the most valuable instrument ever pre- 

 sented to man's hand, and the key 

 which has unlocked for him all the 

 regions of the world. 



By this discovery man surpassed 

 all the animals, and first established 

 his right to be considered lord of the 

 world, inasmuch as it made it possible 

 for him to convey animals and plants 

 to countries into which they had never 

 come before. 



Training of Domestic Animals. 

 Although we may regard navigation 

 as a characteristic attainment of man, 

 we cannot apply the same terms to 

 the training of domestic animals, as 

 there is one animal which also pos- 

 sesses domestic animals, and makes 

 use of their products. 



This is the ant. Like all hymen- 

 optera the ant is remarkably fond of 

 the sweet juice secreted by aphides ; 

 they do not only visit the scattered 

 colonies of aphides in their settle- 

 ments in different plants, but for 

 the sake of convenience, seize the 

 defenceless creatures and carry them 

 off to the ant-hills where they can 

 attach them to the underground roots 

 of grasses. This is done in order 

 to " milk " them, which is done by 

 stroking the hind part of the abdomen 

 till the sweet juice is excreted. 



At other times the ants allow the 

 aphides to remain quietly on the plants they have selected for 

 themselves, and then construct a covered way from the ant-hill to 

 the colony of aphides, by which they can approach them unseen. 



22 * 



