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moved to a little diftance from the eye, will 

 }ofe (by the interpofition of the air) fome of 

 their luftre ; and by being farther removed they 

 will lofe more of it, till they appear, as it 

 were, colourlefs : for if feveral men, cloathed 

 in feveral very different and glaring colours, be 

 placed on a diftant mountain's edge, juft within 

 the utmoft reach of the eye, we may difcover 

 thefe mea as objedls diftinét from each other, 

 but without any other colour than what is caufed 

 by feeing them through a great fpace of greyifh 

 air ; fo that very diftant objedls may properly 

 be faid to have neither light, fhadow, nor co- 

 lour. Any common obferver may perceive, 

 when he commands an extenfive profped, where 

 there are ranges of diftant hills one behind ano- 

 ther, that the moft diftant are of a flat, faint, 

 bluifti colour, without any lighter or darker 

 parts, and confequently without any diftindl ob- 

 jets vifible on them ; therefore, if you would 

 make a pi6lure appear like nature, your great- 

 eft diftances muft be faint. Thofe hills, that lie 

 a little nearer, may ftiew fome fmall diftindion 

 between wood-lands and the bare furface of the 

 ground j on others, ftill nearer, we may diftin- 



guiffe 



