80 The^ARRnR'sNei^jGrnde. Gmap.XXIV. 



jng put too early to hard Labour, and owe theif Difeafes 

 in the Eyes more lo thefe Errors, than either to the Moon 

 or to their Sire. 



CHAP. XXIV. 



Of Films, JVebSy and other T^ifeafes of the 

 Eyes of Horfes, caiifmg Dimnefs or Lofs 

 of Sight » 



External Blind- \JiT^ often obferv'c, after a Horfe has been 

 Tie/s from Films y VV ^^^^ ^jj^g troubled with a Defluxion 

 ond Scars on of Rheum, or Other Dilbrders in his Eyes, 

 ihc Cornea. jj^^j^ ^j^j^^ Subllances grow over them, foas 

 to obfcure the Sight, and thefe fometimes adhere fo clofely 

 to the Eye, that it is very hard to remove them ; fome- 

 times from the fame Caules, or from fome flight Wound, 

 the Cornea, or horny Coat of the Eye, is rendcr'd obfcure, 

 that the Light cannot pafs through it ; for when it is fret- 

 ted by the Corrofion and Sharpnels of Matter, and its 

 Subftance abraded and wore ; or if that happens by any 

 outward Accident, its Reunion may ealily become imper- 

 feft, becaufe of" its exquifite Fincnefs, which cannot be 

 again equally united, but, like a Darn in a Piece of fin6 

 Lawn, will appear with a vilible Blemifli, and become 

 more or lefs injurious to the Sight, according as the Eye: 

 hiis been more or lefs hurt. 



. Sometimes the Caufes of Blindnefs c.r 



\Lheinurnal Dimnefs are more internal, and, according 



• ' ^ to fome, may proceed from a Condenfatioii 



moitrs, or inner' » c ^ ii r u r- 



tnoji Parts of °^ Curdling of the Humours of the Eye ; 

 the Eye. wittch though they be naturally clear and 



tranfparent, yet by exceflive Heat they be- 

 come thick and opaque, like the White of an Egg wheii 

 it is boil'd. Sometimes Blindnefs is occafioned by fome 

 l-'oreign Subftance gathered in the watry Humour of the 

 Eye, which at length increafes fo as to hinder the Light 

 from paffing through the cryftalline and glally Humours 

 into the Retina, or Bottom of the Eye. "Lhis Deftift in 

 a human Eye h C2dkd a. Cataraely and is the fame which 

 the Farriers diftinguifh by the different Names of a 

 Sped, Pearl, or Dragon, according to its different Ap- 

 pearance?, 01 according to the Progrefs it makes on the 



Eye, 



