84 The FarrierV New Guide. Ch. XXIV. 



*' which Difeafe the Animal we are treating of is much 

 *^ fubjedl to, though we have not fo proper a Term for 

 " it as this is. ; 



But a late eminent Phyfician has obferved, that thefe 

 Reprefentations cannot be occalioned by any Kind of Mat- 

 ter floating in the watery Humour, becaufe the Pofition of 

 the Retina^ and Convexity of the Cornea is fuch, that all 

 Bodies muft be placed at a greater Diltance from the Eye 

 than the aqueous Humour, or the Cornea^ to caufe fuch 

 Appearances ; and therefore he fiiys, thofe Signs can only 

 be exhibited, when the Part5 of the Retina are over-much 

 comprefled by a Diftention of the Arteries. And this may 

 jin t* Q. happen, and is oftentimes the Caufe of a 



Blindnefs which we mentioned, viz. where 

 the Eye feems to have no vifible Defed in it. And there- 

 fore, as that Author has obferved, whenever thofe Signs 

 appear with a Cataradt, any fuch Cataradt muft at the 

 fame time be accompanied with a Gutta Serena ; for a Gut' 

 ta Serena is often the Concomitant of other Difeafes of the 

 Eyes, but is only diftinguifhable as fuch, when the Cornea 

 and Humours are tranfparent. 



tr, c- Now I am apt to believe, there are but 



very few who have bought many Horfes, 

 and have not had Experience of this Sort of Blindnefs 

 to their Colt. And the Signs that Mr. Snape has attributed 

 to a Catarad, when a Horfe ftarts with his Head, if that 

 is not the Effedt of Fear, it is, no doubt, to be fufpedted 

 as a Token of bad Eyes, and to denote that Imperfedion 

 which we are now treating of : But there is one, which is 

 the moft infallible, and more to be depended on than any 

 other, viz. When a Horfe moves his Ears backwards and 

 forwards, and often points them towards his Eyes, as if 

 he wante'd to drive away Flies, when there are none near 

 him : And if he renew his fhaking of his Ears, as often as 

 he is turned to a new and different Light, it may be then 

 with very good Reafon fufpeded, his Eyes are defective, 

 though nothing appears outwardly upon them \ and this I 

 have oftentimes obferv'd in Horfes that wereili-fighted, and 

 have known it fometimes the Fore-runner of abfolute Blind- 

 nefs. 



Thefe being the Signs of a Gutta Serena^ and the imme- 

 diate Caufe being a Diftention of the fmall Arteries prelTing 

 upon feveral Parts of the Retinay as was qbferv'd -, what- 

 ever 



