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of vision has encreased to the dimensions of a circle about 

 four or five inches in diameter, which enlarges to twenty or 

 thirty when he attends to the space 'vhich both of his arms 

 can describe or encompass, while all the objects in view ap- 

 pear painted within its area much larger than at first, much 

 smaller than afterward, and nearly within reach of the hand. 

 The eye of man is-fitted by the Wisdom of Nature to behold 

 commodiously at a single glance all objects that present 

 themselves within a cone whose sides form an angle of about 

 sixty degrees, and whose apex is the eye. This cone em- 

 braces but one-sixth of the horizon ; yet so quick is the mo- 

 tion of the eye, that we believe we see a hemisphere at once, 

 which we only take in by successive glances. For the con- 

 venience of beholding the greatest possible number of ob- 

 jects, it is established, either necessarily, or arbitrarily, that 

 the more remote an object is situated, the smaller it appears ; 

 otherwise a multitude of those which under our present cir- 

 cumstances we are capable of perceiving, would be con- 

 cealed from us by the intervention of that single object which 

 happened to be nearest. I'his is not the place to enquire by 

 what means this law is carried into effect. It is sufficient to 

 know that the nearer we suppose an object to be placed, the 

 smaller we judge it to be; and a castle of a hundred feet in 

 altitude at the horizon, will appear scarce an inch to the in- 

 fant that believes it to exist almost within reach of its hand. 

 Thus we can readily conceive that the more distant an object 

 really is, the smaller it must ever appear; and the nearer we 



