they abfolv*d their Relation. But it was not fo here with the 
Apparenees in Venus. For one fees them but for fo fmall a time 3 
that it is far more difficult , certainly to know, when they return 
to the fame place/ 
Yet this I can fay, (Tuppofing that this bright part of Venus y 
which I have obfervd, efpecially this year 1667, hath alwayes 
been the fame) that in lefs than one day it abfolves its motion, 
whether of Revolution or Libration , fo as in near 23 hours it re- 
turns about the fame hour to the fame fcituation in this Planet 5 
which yet happens not withoutfome irregularity. Now to af- 
firm, (Tuppofing it to be alwayes the fame bright part) whether 
this Motion is made by an entire Revolution , or by a Libration , 
I dare not yet doe, in regard I could not fee the Continuity of 
the Motion through & great part of the Arch,as 1 did in the other 
Planets. And for this very reafon, that mW alwayes be difficult to 
determine. 
An Extract, 
of a Letter , mitten by J. D ENIS, TtoBor of Phyfickj and 
P%pfefor of Philo [of by and the Mathematicks at Paris, touching 
a late Cure of an Inveterate Phrenfy by the Transfufion of 
Bloud. 
This Letter ‘was lately fern by the Auth r hi'mfelf to the PubJifher, as it 
was printed at Paris in French * the fubfiance whereof is in Engliffi, as 
follow es, ,, 
I T is now almoft a twelve-month that I declared my {elf pub-. 
lickly iri this matter of Tramfufion y and after I had grounded 
my Conje&ures upon divers reafons, and a number of Experi- 
ments which T made joyntly with M. Mmmerez , I refolv’d to 
expert in the fequel a further confirmation, by carefully obfer- 
ving all that ffiould happen in the feverall Trialls, I intended to 
pradfcife. 
In this refolution we have fince let flip no occafion, to im- 
prove this Operation, which hath been follow^ with good fuc- 
cefs, and I could here alledge feme particular Relations , the 
circumfiances of which would appear curious enough, if I did 
not 
