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the company (wherein his Lp. was seconded by Dr. Wilkins) that Sr. P neil had already some years agoe obserued the like
difference in the air, & tht sometimes in a very bright sky he could see nothing distinctly in the celestiall bodys, but
at other times the Sky being serene after a good shower of Rain, that had swept down store of terrestriall effluviums
mingled with the air, and hindring the free passage of the Starry beames he could see those bodys very distinctly.
mr. Hooke was thanked for these obseruations, and desired to continue there for further confirmation and it was
orderd that the paper should be registred. mr Hooke produced a pair of scales in a box to make experiments
wth. vpon a good Loadstone, for the finding out of the decrease of the attractiue force vpon a body according as it is
placed at greater and greater distances, in order to find /out/ whether grauitation be somewt magneticall, which he said might
be done by comparing the distances of the bodys made vse of in the experiments, from the superficies of the earth &c
Loadstone wth the diameters: It being probable that if they hold the same proportion they haue the same cause. It
was orderd that he should make in it seuerall Expts. by himself and then make them before the Society. (from Green prsent
1 wild peniroyall or bastard dittany. 2 pistolochia. 3 virginia scorzonera. 4 faba Egyptiaca a great Restoratiue) moray about
silkwormes & mulberys in Virginia) Enquirys to be made about obseruation made in the Late Plague). more silk pods rom virginia)
mr. Boyles Origine of formes prsented.)
Aprill 4. 1666. (comtee of accounts) There was presented by mr Hooke a table of the degrees of the Loadstones attraction of a Little
square oblong peice of iron at seuerall distances from the pole of the magnet, as he had found in making tryalls priuatly
himself. at 6 inches. 0. at 4 inches 1/8 gr./ at 2 inches. 13/16 gr./ at 1. inch 17 6/8 gr./ at 1/2 inch. 57 6/8 gr/ at 1/4 inch 104 5/16 gr./ at 1/8. 197 4/8.
which tryalls being repeated before the company held good except that insteed of the 2 13/16 at 2 inches distance the -
weight was 3 3/4 graines and insteed of 17 6/8 gr. at 1 inch distance the weight was 18 7/8 gr to equall the attraction.
There was also a thin plate of steel interposed at about an inch and that made the weight lesse by 14 graines. (about Cap=
ping Loadstones) mr Ball to send vp magnetick apparatus) mr. Palmer 95 neurinburg cupps.) about husking rice qu)
Apr. 11 1666. Election day. accounts. &c. Sr. R moray presented conditionally the Stones out of the heart of the Lord Belcarris.
Aprill 18. 1666. There was produced by mr Hooke a new kind of watch whose motion is Regulated by a Loadstone the
ballance of it being a rod of steel. corcerning which the Pt. affirmed declared that this way might doe best of all
in case the magnet kept always the same temper. The springy saddle contriued by the same was tryed and an
exception being made against the narrownesse of the seat and the way of hanging on the stirrups it was ordered
that against the next Day it should be made with a full seat & wth. the stirrups hanging from the seat it self.
(mr. Boyle about sounds) about transfusion) Dr Charlton of Blood) about injection) Oldenburg German turning.) mr Streaters
egge painting) mr Pouey offered to goe with mr. Hooke to the artist. there to see the operation it self his offer
was accepted and mr orderd to attend him accordingly (he promised a skeleton).
Aprill. 25. 1666. . . . mr. Hooke shewed by a terrella that the Lines of a Loadstones Directions are all ovalls
of wch. the center of the magnetick Globe is the place of contact, and the axis of them perpendicular to the axis
of the terella. this was performed by suspending and Letting freely moue a needle vpon a small triangular
peice of wood and marking the points of its respect to the magnet all which fell into an ovall. he offerd his -
[In margin]Vz   thoughts of an hypothesis to explicate all the phaenomena of a Loadstone which he was desired to giue in the
next Day. The same affirmed that he had put all sorts of bodys between a magnet and Iron. and none did
alter the attraction saue Iron. (mr Boyle proposd to examine the epicurean & cartesian hypotheses) also Dr Godderd) The Dire
tiue vertue of the Loadstone was tryed by putting a magneticall needle vnder water where the needle kept the like posture vpo
the approach of the Loadstone that it does in the air. (about changing water into earth. -
May. 2. 1666. The expt. of the Loadstones attraction in water was tryed: and it was found that the Loadstone and
the iron ball touching one another vnder water held 128 graines before they were separated. and the water being -
drawn off from the Loadstone and the Loadstone dryed. the two bodys held very neer the same weight before separation
soe that the magnet seems to be as powerfull in the water as in the air. (Dr. Goddard q whether the distance of Attraction the same-
as in air) minerall from Guine) mr.Chumly the making of allum) The Expts. were made with two Loadstone, one a terrella
the other of an Irregular figure and some steel dust being scatterd about them there appeard vpon the different position of
the Later in Respect of the former, different and odde postures in the said Dust. mr Hooke was orderd to describe
these postures in Schemes and to bring it into the Society (mr Powle brought in the History of Iron. or an account of the
manner of its preparation in the forrest of Dean. Registred)
May. 9th. 1666. (Petrus Lambiecius his book presented) Historia Literaria which vndertakes to giue account of the Rise progress
fall & Restoration of Languages Sciences & Arts from the beginning of the World in this age as also of the men famous for Increasing
& promoting knowledge vizt when & where they liued & what they wrote & contributed. of wch booke there being extant but
one tome yet the Author intimates the Empr. hath ingaged him to proceed wth the rest). about Mummy.) wallis his hypo
thesis for soluing all the phaenomena of the flux & Reflux of the sea vpon the consideration of a common Center
of Grauity of the earth & Moon) Auzouts Letter about Diuinjs discouery of the permanent spot in Iupiter
a Relation of 2 Rainbows - 4 suns at Chartres.) There were made 2 magneticall Expt. by mr Hooke one was that
the terrella being soe posited as to haue its poles perpendicular to the horizon the steel Dust held ouer it in a siue &
put into motion was insteed of being attracted chaces away from both the poles. in 2 seuerall tryalls. & the same terrella
being placed horizontally and the steel dust held againe ouer it. I was likewise driuen away from both the poles at once
the same was tryd wth. a magnet of an Irregular figure with the like successe. the 2d Expt. was that the terrella being put
into the midst of a boord in a hole and the steel Dust Ranged in Ouall figures about it a small Loadstone
being placed on the same boord, the dust when put into motion. was determined by it into analogus Ouall figures

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