ersities_,
but never yet upon more than one Dog at a time, for want of leisure, and
convenient supplyes of several Dogs at once. But when I return, I doubt not
but to give you a fuller account, not only by bleeding several Dogs into
one, but several other creatures into one another, as you did propose to
me, before you left _Oxford_; which will be very easie to perform; and will
afford many pleasant and perhaps not unuseful Experiments.

But because there are many Circumstances necessary to be observ'd in the
performing of this Experiment, and that you may better direct any one to
doe it, without any danger of killing the other Dog, that is to receive the
others bloud, I will mention two or three.

_First_, that you fasten the Dogs at such a convenient distance, that the
Vein nor Artery be not stretched; for then, being contracted, they will not
admit or convey so much bloud.

_Secondly_, that you constantly observe the Pulse beyond the Quill in the
Dogs _Jugular_ Vein (which it acquires from the impulse of the _Arterious_
bloud:) For if that fails, then 'tis a sign the Quil is stopt by some
congealed bloud, so that you must draw out the _Arterial_ Quill from the
other, and with a _Probe_ open the passage again in both of them, that the
bloud may have its free course again. For, this must be expected, when the
Dog, that bleeds into the other, hath lost much bloud, his heart will beat
very faintly, and then the impulse {356} of bloud being weaker, it will be
apt to congeal the sooner, so that at the latter end of the work you must
draw out the Quill ofter, and clear the passage; if the Dog be
faint-hearted, as many are, though some stout fierce Dogs will bleed freely
and uninterruptedly, till they are convuls'd and dye. But to prevent this
trouble, and make the experiment certain, you must bleed a great Dog into a
little one, or a _Mastive_ into a _Curr_, as I once try'd, and the little
Dog bled out at least double the quantity of his own bloud, and left the
_Mastive_ dead upon the Table, and after he was untyed, he ran away and
shak'd himself, as if he had been only thrown into water. Or else you may
get three or four several Dogs prepared in the same manner; and when one
begins to fail and leave off bleeding, administer another, and I am
confident one Dog will receive all their bloud, (and perhaps more) as long
as it runs freely, till they are left almost dead by turns: provided that
you let out the bloud proportionab