80 The ^KR^nTK*s New Guide. Chap.XXIV. 



ing put too early to hard Labour, and owe their Difeafes 

 in the Eyes more to thefe Errors, thwi either to the Moon 

 or tp their Site. 



CHAP. XXIV. 



Of Films y JVebSy and other T>ifeafesofthe 

 Eyes of Horfes^ caufing Dimnefs or Lofs 

 of Sight. 



Externa! Blind. "Vl/E often obfervc, after a Horfehas been 

 nefsfroni Films, V V ^^^^^^ ^j^g troubled with a Defiuxion 

 and Scan on of Rheum, or other Diforders in his Eyes, 

 the Cornea. jj^jg ,^^^ Subftances grow over them, io as 

 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 Caufes, or from fome night Wound j 

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

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

 ted by the Corrolion and Sharpneis of Matter, and its 

 Subilsnce abraded and wore ; or if that happens by any 

 outward Accident, its Reunion may eafily become impef- 

 fecl, becaufe of its exquifite Finenefs, which cannot be 

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

 Lawn, will appear with a vifible Biemifb, and become 

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

 has been more or lefs hurt. 



^, . Sometimes the Caufes of Blindnefs or 



jo£ internal Dinmefs are more internal, and, accordint^ 



from the tin- , r ^ c Z. n> a r ■ 



^ to fome, may proceed from a Condenlation 

 7noi{rs, ontvur- ' -^ r , tt r x, t- 



moft Parts of *^^ curdling of the Humours of the Eye ; 

 the Eye. which though they be naturally clear and 



tranfpirent, yet by excei]i\'e Heat they be- 

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

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

 Foreign Subitance gathered in the watry Humour of the 

 Eye, which at length increafes (o as to hinder the Light 

 from pafling through the cryftalline and glafiy Humo'ors 

 into the Retina^ or Bottom of the Eye. This Defevft in 

 a human Eye is called a 6j/j,'Y2t7, and is the fame which 

 the Farriers diftinguifh by the different Names of a 

 Speck., Pearl., or Dragon., according to its difterent Ap- 

 pearances, or according to the Progrefs it -makes on the 



Eye, 



