[ 3 ] 
mentioned Time, had not a Misfortune happened to 
its Cafe which made it not perform quite fo much. 
It appeared to me fomewhat extraordinary, that 
the Circumference of its firft Mover (I mean any 
^determined Part thereof) paffed through a Space of 
4.2 Feet in 20 Seconds; which is nearly twice as 
faft as the Motion of the Water: And as the Mo- 
mentum will be in proportion to the Number 
of the Sets of Sails that are employed, its Force is 
capable of being greatly augmented with the fame 
Quantity of Water-: A Thing not to be admitted 
without fufficient Experiment, but what feerns ex- 
tremely plain in Theory, and what I am- apt to think 
will anfwer when brought to Pradice. 
This Engine, when once fecn, rcquircslittlc Skill" 
for the Conftrudion of it, is made at a fmall Expence, 
and kept in Repair with Eafe. 
DR. SALTER, one of the Prebends of Norwich 
Cathedral, writes, in a Letter to Mr. Arderon, that, 
upon feeing Mr. Baker’s Communication of the Ufe 
of the Jelly, or rather Rob, of black Currans m 
curing fore Throats, 1 Xranf. N°. 459. p. 655. he 
thought it might be of Service to take notice of the 
following Effed of the Jefuit’s Bark : The Dodor 
ufed to be fubjed eafily to take Cold, and, in con- 
fequence thereof, to be fubjed to have a fore Throat 
to a very great Degree ; but the laft time, above 1 5 
Years ago, after his Recovery, he was advifed, by 
Sir Benj. Wrench , to take two Ounces of the Bark 
(after due Preparation by Bleeding, or Purging, or 
both, when he was altogether without Complaint) 
every Spring and Fall. This, he faid, would more 
A 2 effedually 
