Packard.] INSECTS AS ARCHITECTS. 315 



about thirty fe5t. Another species in Brazil, according to 

 Rev. Hamlet Clark, will tunnel a ditch, and he adds, " Indeed, 

 I have been assured again and again by sensible men, that 

 it has undermined, in its progress through the country, the 

 great river Paraiba, as broad as the Thames at London 

 Bridge ; at any rate, without anything like a natural or arti- 

 ficial bridge, it appears on the other side and continues its 

 course." 



It would be exceedingly interesting to watch the succes- 

 sive steps of this tunnelling process, to learn how they plan 

 their work, how the mine is run under the stream with such 

 true engineering skill from one side to the other ; how the 

 danger of undermining and flooding are overcome. Here 

 we have a slight anticipation of the Thames tunnel, though 

 this is said to have been suggested by the tunnel of the 

 ship worm, which lines its hole with limestone. 



Ants also dig wells. The same Texan CEcodoma, we are 

 told by Dr. Lincecum, needs water as much as cattle or men, 

 and like the latter t^iey dig their own wells. In one case, 

 where a man dug a well reaching water at a depth of thirty 

 feet, the ants dug a well to the same depth, with a diameter 

 of twelve inches. 



As mound builders the ants are indefatigable. With the 

 aid of their jaws they carry out grain after grain of sand, 

 and from being primarily tunnellers, they become mound- 

 builders. An ant hill, common object as it is, is a marvel 

 of patient and untiring labor. Think of the toil and mus- 

 cular exertion spent by these ants in climbing from the 

 depths below up the perpendicular walls of their nests with 

 their burdens ; and busy as they appear to us by day, they 

 are said to do the greater part of their work by night. In 

 clayey countries in Mexico the Oi^codomas build enormous 

 ant hills, "so that one perceives them from afar by the pro- 

 jection which they form above the level of the soil, as well 

 as by the absence of vegetation in their immediate neighbor- 



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