74 ^^^ '^*'^ 0/ Farriery 



fince we find by the Barometer, that there is three 

 Inches DifFcrence between the greateft and the lead 

 Gravity or Elafticity of the Air, which is a tenth 

 Part of its greatefl Gravity, there mail be likewile 

 the Difference of a tenth Part of its PrefTure tipoii 

 the Lungs at one Time more than another. For 

 the Mo7}ientu7n of all Bodies, moved with the fame 

 Velocity, are as their Gravities. 



This is a Difference which fuch as are aflhmatick 

 (or what in Horfes is generally called broken 

 winded) mufl be very fenfible of; efpecially if we 

 confider, that they likewile (I mean the Aflhma- 

 tick) breathe thicker, that is, every Expiration is 

 performed in lefs Time : And if in half the Time 

 (as is common by Obfervation) and the fame Quan- 

 tity of Air drawn in, then the V/eight of the Air 

 upon the Lungs mufl: be 57648 Pound, of which a 

 tenth Part is 5764 Pound : (I mean this Calculation 

 for human Bodies). And in fuch Cafe, afthmatick 

 People, upon the greateft Rife or Fall of the Barome- 

 te,r, feel a Difference of the Air, equal to above 

 one Third of its Preffure in ordinary Breathing. 



Lafil^y if the Afpera Arterla or Wind-pipe is fraall, 

 and its Aperture or Orifice, at the Larynx or Top of 

 it, of a narrov/ Conformation, the PrefTure of the Air 

 increafes in the flime Proportion, as if the Times 

 of Expiration were fliorter ; and upon this Account, 

 A iliviU a fhrill "Voice is always reckoned among the pro- 

 P ^^'^oftickS^^^^"^^ Signs of a Confumptlon, becaufe that pro- 

 Sign oi" a ceeds from the Narrcwnefs of the Larynx or Orifice 

 Confumpti- of the Wind-pipe ; and confequently increafes the 

 on in Man. PrefTure of the Air upon the Lungs, which upon 

 every Expiration, beats the VefTels fo thin, that at 

 laft they break ; and in human Bodies, as a Spitting 

 of Blood brings on a Confumption apace, fo in Hor- 

 fes it is nearly the fame : For I have feen fuch thick 

 v/inded Ones often troubled with Bleeding at the 

 Nollrils, l^c. which mollly terminated in the Glan- 

 ders, and Death in the End. 



I think 



