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Ian. 14. 1668/9. - the Curator shewed by two sorts of Expts. that the force in moving bodys is in a duplicate
proportion to their celeritys, soe tht there is required a quadruple weight to double the Velocity. the first Sort was
made by a pendulum made after the manner of a fly counter poysed: which was seuerall times repeated with the
Successe expected, there being made 12 vibrations with the weight of two ounces, and twenty four vibrations
with the weight of 8 ounces and 48 vibrations with two pounds weight all in the Same time. The other
Sort was with running water whereby it appeard that the falling water was to be raised 4 times the height to run out wth
Double the celerity. this Later was orderd to be repeated the next Day, because the vessell Leaking hindred somewt the exactness
of the experiment. The Curator produced an instrument with a wheel to perform the same thing in a horizontal posture
-ition. this way was orderd to be tryed the next meeting. -- mr Oldenb: read Letters. 1. from Heuelius - dated dec: 11. 1668 SV
wherein the author - - - answers 7 querys proposed to him in a Letter by the Secretary from Mr Hooke concerning his
Cometicall obseruations. 2ly &c -
Ian 21. - the Expt to shew that the water is to be raysed 4 times as high to run out with Double the velocity, was
repeated with this effect that the water raised at that height ran out with some what more then double the velocity [Vz
all indeauours vsed to elude Expts. and peruert the record of them]. The Bp of Sarum moued that this Expt might be tryed
in a triplicate triple proportion to see whether water raised nine times as high would run out with thrice the velocity. It was
ordered that the next day it should be tryed accordingly. - (M Boyles expt. of Liquor in Exhausted cane beating against the bottom
he desired to direct varying it & mr Hooke to Receiue the same.) Mr. Hooke affirmed that the Vibrations of a Pendulum of 8 foot long
with a weight of 8 pounds (which was of a conicall figure) Lasted aboue 8 howres. - D Croons hypothesis of motion . . .
Mr Griffiths present from turky. a stone giuen to Mr Hooke to put in the Repository. - about transfusions.
Ian. 28. - The curator made an Expt. tending to shew that a body once put into motion would moue perpetually if it met wth
noe resistance. this he did by hanging a wheel having a pointed peice of Iron in it on a capped Loadstone and putting it into
motion by a pair of bellows, whereby the wheel conteined its motion for a considerable time as hauing but Little resistance
which was noe other than tht of the air in which it moued round, It was suggested that it were worth obseruing how the ve
Locitys of this motion decreased in aequall times. -- about Ioachim Iungius.
Feb 4. Seuerall Expts. made with Balls to verify Dr Wrens Laws of motion: and other particulars concerning them. & about Cyphers
Feb. 11. The Curator Absent a Comitte appointed for Expts. [which neuer did any thing] The operator orderd to speak to Mr Hooke that the
new great microscope of Mr Coxes making be brought to the Society the next meeting -- about plyable wax. minerall waters
Feb. 18. The Experiments of motion were prosecuted with Springy bodys. by which it appeared to some of the Company that the
Laws of Motion Establishd by Dr Wren, were best verifyed by the motion of the most Springy bodys. Orderd that these tryalls
be continued the next Day. -- Malpighius his pacquet about Silk wormes, orderd to be perused against next Day by Mr Olden
& Mr Hooke. - about flying cobwebbs. -- Bertrand De La Costa's machin. -- Mr Coxes microscope Described.
Feb: 25. There were some expts. made to finde what would be the resistance of air to bodys moued through it with seuerall
velocitys, & it seemed ^/tht/ the Larger the arch was in which the pendulous body moued, the more impediment it sufferd
from the air. and the slower the it moued through the air (as when it moued in a Smaller arch of a circle, the Lesse
stop it receiud from the impediment of the air, and the impediment to motion decreased in a greater proportion
then the decrease of the velocity. but what the exact proportion of the Decrease was, was to be found out by further tryall
It was orderd that this kind of Expts. should be presented the next Day. by employing boords or plates of Seuerall expan
sions, but all of the same weight, and with balls or boords of seuerall weights, but of the same Expansion.
The Curator proposed an Expt. to find out how the magneticall power Decreaseth at Seuerall Distances. and promis
-sed to bring in at the next meeting a Watch whose Ballance should moue by the force of a Magnetick Steel.
Dr. Holders Elements of Speech presented. -- mr Hooke reported to the Company that he had perused Sigr. Malpighi's
Discourse about Silkwormes, and found it very Curious and Elaborate well worth printing. this was seconded by
Mr. Oldenburgh, who thereupon &c --
March 4. There were made some more expts. to find what is the resistance of the air to bodys moued through it
with Seuerall Velocitys. which was at this time done with Seuerall weights fastend to the same area of a thin
Latten plate. [some of the Results are set down but Rudely.] -- It was orderd that these Expts. should be va
ried the next Day. by applying the same weight to seuerall areas. -- a Palm Leaf viewd in the new
microscope. Dr Lower tractus de Corde presented. Vz -- It being mentioned that the aequi-
-nox being neer at Hand. some care might be taken of obseruing the precise time of the Suns entrance into Aries,
Mr. Hooke said that he Intended to make a fitt apparatus for it against the next Autumnall AEquinox.
Expts. for the next Day, besides &c. -- were ordered, the Curators magneticall watch. as also &c --
Mar. 11. (about Expts. of motion. &c -- the Curator orderd to take care they be done next Day. New microscope to be new
contriued.) Item that the Curator should bring in his new contriuance for a Watch sayd to moue by a Ballance
toucht with a Magnett as also that he should not forget the Expt. of falling Mercury in a glasse cane. --
mr. Hooke affirmed to haue examind some froggs, and found in them a Seminall and excrementall Vent.
He also lookd vpon the black round Spawn of froggs by a Microscope & thought he Saw a whitish tegument round
about the blackish Substance, and was of opinion that that was like the white of an Egge, as he ghessed the black
matter within to be instead of the yolk. he vndertook to obserue the progresse of froggspawn from time to time
The President moued that since there was soe great a necessity of having more curators then one the
society would Recomend it to the Councell to consider of it as a thing of soe great concernment to the Society
advancement of their institution, and it was accordingly referred to the Councell.
March. 18. the Curator tryed something in order to make a watch goe by the force of a Loadstone
It was orderd that he should prouide against the next meeting, an house clock going half Seconds &
put a flight vpon it to try what the power of the magnet will be would be. -- It was taken no
tice that if this contriuance would be made practicable, the Magnet would then furnish the nauigator
with the Longitude as well as it hath hitherto aduantaged him with the Latitude. -- Dr Croon propos
an expt. to try whether an animall would be fed by blood alone transfused into it. vizt. by inclosing 2 doggs
in a box and making the blood circulate from one to the other by the way of transfusion feeding
the one & not the other. he was Desird to make the Expt. and D Allen & mr Hooke to assist him in it
Apr. 1. 1669. -- Apr. 8. There was made one of the expts. appointed the Last Day vizt that with Gutts . . . /blowen/ vp and
Howev tyed on both ends, to shew that for making a pulse in the arterys, there needs noe more than a compressio
in the heart, for as much as the gutt being Compresst on one end, the motion of it was sensible at the other end.
Dr. Goddard excepted that this was not enough sufficient to make out what was intended, since there was noe
out lett in these Gutts, whereas there was an issue of the blood in the body of animalls out of the arterys into the
Veines. Mr. Hooke answered that though there was soe, yet there being a return of the blood to the heart again
It could not be otherwise but that the vessells being full, there would vpon the circulation of the blood into the
heart again and its Systole, be caused a sensible pulsation in the arterys. the same proposd an addition of
a pipe to this Expt, the Better to shew the tryall of his assertion. the same produced some plano conuex glasse
as small as pinns heads to Serue for Obiect glasses in microscopes. He was desired to put some of them into the great
Microscope of the Society for a tryall.-

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