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they absolv'd their Relation. But it was not so here with the Apparences in Venus; for one sees them but for so small a time, that it is far more difficult, certainly to know, when they return to the same place.

Yet this I can say, (supposing that this bright part of Venus, which I have observ'd, especially this year 1667, hath always been the same) that in less than one day it absolves its motion, whether of Revolution or Libration, so as in near 23 hours it returns about the same hour to the same scituation in this Planet; which yet happens not without some irregularity. Now to affirm, (supposing it to be always the same bright part) whether this Motion is made by an entire Revolution, or by a Libration, I dare not yet do, in regard I could not see the Continuity of the Motion through a great part of the Arch, as I did in the other Planets: And for this very reason, that will always be difficult to determine.

An Extract

Of a Letter, written by J. Denis, Doctor of Physick, and Professor of Philosophy and the Mathematicks at Paris, touching a late Cure of an Inveterate Phrensy by the Transfusion of Blood.
This Letter was lately sent by the Author himself to the Publisher, as it was printed at Paris in French; the substance whereof is in English, as follows.

It is now almost a twelve-month that I declared my self publicly in this matter of Transfusion, and after I had grounded my Conjectures upon divers reasons, and a number of Experiments which I made joyntly with M. Emmerez, I resolv'd to expect in the sequel a further confirmation, by carefully observing all that should happen in the several Trials I intended to practice.

In this revolution, we have since let slip no occasion to improve this Operation, which hath been follow'd with good success, and I could here alledge some particular Relations, the circumstances of which would appear curious enough, if I did

not