INSECT ENGmEERma. 



199 



FIG. 67.— BALLOONING SPIDER PKEPARING TO ASCEND. 



that the little aranead produces, by lengthening hbr 

 lines, a result similar to that of the human teronaut who 

 throws out his ballast of sand ; and, by gathering in the 

 lines, accomplishes what ballooning man performs when 

 he pulls the valve and permits the gas to escape." 

 "To return to our bridge. The orbweaver when 



