( S>c6 ) 
CO ROLL ARY III. 
That Volatile Salts have a great property to draw 
Tinctures, and do particularly advance thofe Colours 
that are difposd to be Red : For tho' Spirit of Wine be a 
very Catholic Menftruum % and draws a very deep Tin- 
Sure of Cochinel, yet we have often obferved that if 
we put to this Tin&ure, when higheft, a fmall propor- 
tion of Volatile Salt that would advance it to a great, 
even a double degree. Thus I have obferved it to ad- 
vance the Tinfture of Arterial Blood ; and which is very 
Curious, if you difiblve it in your Blood whilft } ou are 
Bleeding at one of your Veins, that Blood will become 
very florid, and like Arterial Bleed. Therefore fmce 
Nitrous Salts produce none of thefe tingeing Effe&s ; 
this Corollary ftems much to favour the Notion, That 
the Effe&s of the Air upon the Blood, may be due to 
fuch Salts as are of a Volatile Alkalifat Nature. 
COROLURY IV. 
Contagious Difeafes are Communicated by the Air 
infpired at the Lungs ; and thisfeems more probable than 
what Dr. Nec&am and others, have endeavoured to 
make out with more difficulty ; in attributing the feme 
e9e& to the Air taken in our Meat by Maftication, and 
fwallow'd down in our Drink, and communicated t© 
our Chyle from thence to our Blood an J Spirits ; but this 
way a very fmall quantity of infeftcd Air is Communi- 
cated, if we compare k with what is Communicated to 
the Lungs : For in each infpiration, Humane Lungs of 
an ordinary fize do at leaft take in fuch a quantity of Air 
as will fill up a Quart Bottle, and in the (pace of a Mi- 
nute i have made Twelve Respirations, ( when I was 
very fedate, and drew in my Breath very treatably) and 
in 
