182 INSTINCTS. 



the construction of the honey-comb. But another 

 problem remained, viz : to determine the precise an- 

 gle at which the three pieces ought to be united to 

 render the structure perfect. " This is one of those 

 problems, belonging to the higher parts of mathemat- 

 ics, which are called problems of maxima and mini- 

 ma. It has been resolved by some mathematicians, 

 particularly by the ingenious Mr. Maclaurin, (one of 

 the most distinguished of the disciples of Newton), 

 by a fluxionary calculation to be found in the Trans- 

 actions of the Royal Society of London. He has 

 determined the angle required ; and he found "by the 

 most exact mensuration the subject could admit, that 

 it is the very angle in which the three planes in the 

 bottom of the cell of a honey-comb do actually 

 meet." 



Another curious example of philosphical instinct is 

 the web of the spider. The web usually consists of 

 circular threads laid round upon straight ones which 

 form the stays that fasten it to the wall. The circu- 

 lar threads are covered with a glutinous substanc e« 

 and by these the food of the animal is caught. But the 

 straight ones, which are more necessary to the web, 

 are not adhesive, and are therefore not permitted to 

 grapple with the fly, so as to be exposed to the dan- 

 ger of being broken by its violence. The same is 

 true of the uttermost thread which encompasses the 

 web, and which is of particular importance to its se- 

 curity. This is not adhesive. The most skilful artist 

 could not have displayed more judgment. 



T. Upon what grounds do you consider the in- 



