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April. 6. 1671. the Curator mention'd a way he had for Discouering the texture of wood, by filling all the seue
-rall pores thereof with mercury, of which he produced a specimen in charcole, promising to shew the
manner of Doing it the next Day.     Apr. 13. noe meeting.
April. 20. the curator shewd the way of filling the seuerall pores in Wood with quicksiluer, doing it
at this time vpon a peice of charcole, He was Desired to bring in an account in writing of the manner
of doing it, as also of what was Discouerd by it all to be registred. Orderd also that the expt. be made
the next day vpon wood not charred. The curator mentiond that he intended to try the same with fine
plaister of Paris; considering that if it will soake in, it will look white enough, and not Reflect soe much
glaring Light as mercury doth. [wallis concerning Leibnitz. Lister of vegetables]
The Businesse of the Burning Concaue being again spoken of, it was thought necessary that the President Mr
Surueyor & mr. Hooke, should be desired to agree vpon the portion of the Sphere or Parabola, that is suffi
cient to make all the Rayes meet in a point, and that Mr Hooke should bring in at the next meeting, a
Demonstration shewing how many Degrees are iust necessary to make all Rayes thus unite.
Mr. Hooke aduanced an assertion, importing that a concaue made of a Little sphere, Reducing all the
beames of the sun into a narrow focus, shall burn stronger then a Concaue made a greater sphere Leauing
the Sun beames more at large, this he sayd was Demonstrable. [montanary of Glasse drops]
Apr. 27. There was made a Microscopicall Expt with a Fungus of wood, which appeard in the microscope
to be all fibrous and to Resemble in its texture to skin tanned. The curator was putt in Minde of Per-
forming at Last his promise of measuring the quantity of a degree vpon the earth. He engaged to doe
it within a month. He was likewise exhorted to prosecute the Observation of the Paralax of the Earths Orbe
concerning which he sayd that he thought indeed, he should find a Paralax, unlesse it be sayd that there may be a Va-
riation in Perpendicularity. Besides he was Called vpon to giue the Demonstration he promised of the quan
tity of the Sphere, that is sufficient to make all the sun beames, meet for a burning Concaue, Not hauing it
ready he was desired to bring it in the next Day. It was also orderd that what he had prepared for the men-
suration of the earth, as also his apparatus for Obseruing the Parallax of the earths Orbe, should be
by him brought in in writing to be enterd in the Register Book, to secure both from the arrogatio
of Strangers. It was also mentiond that the Expt. with the glasse Bell and Powder should be prosecuted
for the Discouery of the Internall motion of Bodys. It was ordered likewise that a Receiuer should be fitted
to the Pneumatick Engine for the putting in of an Arme, and exhausting the air.
May. 4. There was made an Expt. of transmitting mercury through wood, by putting a plugge of willlow wood
at the bottom of a glasse Cane, and powring mercury vpon it, the Successe wherof was that the quicksiluer
made its way through the wood from the Smaller In the end downwards more easily, then from the thicker end
holding the great ends vpward found the water to Drop out at the smaller ends. and doing the same through
the like branches by holding the Lesser ends vpwards, found the water to Drop out faster through the wood
at the greater ends. This peice of wood being cutt the mercury appeard in all the parts of it except -
the pith & Bark, in both which there appeard none at all. This Expt. was also made by Blowing Air
through the same wood with Spittle on it which passed Readily one way namely from the Smaller end
to the greater, and Difficultly the other. It was suggested that this Expt should be tryed, with seuerall sorts
of Wood of Different age and Lengths, & in canes of seuerall Lengths to see what weight of quicsiluer
will passe through what Lengths of wood. It was also suggested that the like might be tryed vpon stones -
metalls especially copper and Iron. [new star in Swan beak. also wthout ansulae. ------
Oldenburg desird that the curator might be put in Mind to obserue the Obscuration of a fixed star by the moon
which would happen according to m Flamsteds preaduertisemt. the 6th. of this month. The Curator was Accor
dingly desired to take notice of these particulars, and ioyne wth. Dr. Pope in Obseruing them. [mariotts manu
script abt. Leuells. deliuerd to Dr. Chr. Wren. [collins about Streining mexican stone. &c.
Monr. Leibnitz his Book called hypothesis Noua Physica was deliuerd to Mr. Hooke to be examind by him.
May. 11. The Curator being called vpon for making the Expts appointed the Last Day of transmitting mercury
through seuerall sorts of wood, and throug Iron, said that he had made one at home with Elder wood and
found noe mercury at all in the pith of it. He addeth that he conceiued the pith to be a congeries of blad
ders having noe visible communication with the other parts of the wood, as the Pith of quills is
also nothing Els but a congeries of Bladders. Orderd that more of these sort of Expts. be made the
next Day before the Society and that that with Iron & quicksiluer be not neglected. -
The same gaue some account of the Obseruations made by him the moon obscuring a fixt starr of the 4th Magn.
may. 6. 71. preadvertisd by M Flamstead. vizt that whereas by mr. Flamstead the time of its ingresse had
been calculated 9h. 9'. 37". he found it enter about 23 min after 9. and that its mora vnder the moon was
as long as had been calculated. vnlesse there were a Difference of a few minutes seconds. he added
that he had made with all this physicall obseruation. vizt. that the starrs of an aequall Distance
from the Light of the moon, did not appear aboue a quarter as big on the light side as on the dark side.
The same deliuerd againe the new hypoth: of M Leibnitz the Last day comitted to his perusall and sayd that he
was not satisfyd with it. [Heuelius Letter of may. 1. 71.] This Gaue occasion to mind Mr Hooke to Ob-
serue this new starr in the Swan: as also to obserue the present phasis of Saturne presumed to appear
near without the ansae. [oldenb. produce mariotts MS.] Mr. Hooke promised to send Mr. Heuelius
a scheme of the Instrument for measuring the Diameters of the Starrs. and taking small Distances as also
to send to m Flamstead his late obseruation of the stellar Eclipe of may 6. 1671 -
May. 18. Lister propoundd by Oldenburg.] ther was made an Expt. with a peice of Green willow cutt asunder &
the small ends dippt in a coloured liquor which filtred vp through it. the Pith also of an elder was Dipped
in a coloured liquor, and it Ran vp the sides of the pith, and not at all the iner parts of it. [flamsteds Letter
] orderd that mr Hooke do comunicate to him his obseruation of that appearance he hauing Earnestly desird it
[Wallis Letter abt. Expt. standing Extraordinary high. query in Letter book. may. 13. 71] Leibnitz letter & book from Maucase
Expts for next day. to prosecute this of the texture of wood. 2 glasse bell and powder. The curator was put in mind to bring in the Demonstration
of the quantity of a shore for a concaue his apparat for measuring a degree. &. Obseruing parallax. Receiuer for Arm. Ring & new starr.

Ref: CELL/RS/HF_089  © Centre for Editing Lives and Letters