(seq. 41)

Lect. 2

Nor Alkaline, but Alkalescent or putrescent, if kept
when first drawn, it is neutral - The Antients thought
it adviseable to give Salts to thin the Blood - But Mix-
tures out of the Body, have not the same Effect, as taken into
the Body, for then they suffer the Powers of Digestion, & cer-
tainly must be very much altered by undergoing this Change.
With Salt of Hartshorn out of the Body, it grows dark Co-
loured, does not jelly, is of a creamy Consistence, & thinner
& with distilled Vinegar, it grows blacker, & somewhat thicker
than the first - With Spirits of Sea Salt, if mixed with Water
it does not Coagulate - but is of a dark brown Colour & keeps
pretty fluid with foliat^d Tartar, the Colour is first very florid
but upon standing soon congeales, & appears, as Blood not
mixed - If Blood after standing a While is not sezy at the Top
it is red, & at the Bottom black, probable from the Action of the
Air, Also from an Experiment of M^r. John Hunter, for in a Vial filled with Blood, & immediately corked, the Part in Conta-
ct with the Cork was of a bright red Colour, owing to a Globule
of Air, that had got in. All the rest was of a dark Colour - The Differ-
ence between the Venal & Arterial Blood is not so great, as has
been Imagined by the Antients. Yet the Blood is of a brighter Colour
in the Arteries, then the Veins, owing probably to its brisker Mo-
tion, & the greater Action of the Arteries upon it, as Venal Blood
shook in a Vial puts on the Appearance of Arterial, hence the
Reason, why it returns so florid from the Lungs, as it moves