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and as deep a screw as may be. (breaking wood more desired) Orderd that these kinds
of Expts. be prosecuted by mr. Hooke in other kinds of wood to see whether the same propor
tion will hold them (monstrous fish horn) weighed in air & water) as heauy again as water
tin oar weight. as 6 1/6 to 1. /to/ water) Charletons Brains) mr Boyle account of light). Packer petrifyd Elm
comittee lists.)-
Iune 15. 1664. Rock salt wth blebs) cussar Sigr Cesare of the chang of meridien Line)
orderd that Sr. Rob: moray mr Ball & mr Hooke to meet at a time - conuenient
for them to make an obseruation concerning the Variation of the needle which
is affirmed by one Bond to be now 1d. 30'. westwards. (Boyle suggests freezing
Loadstone) mr. Hooke affirmed that a loadstone in winter taketh not vp soe much
Iron as in summer. The Expt. of powder in case of steel much stronger then
formerly was again tryed but wthout any report or other visible effect, which
was ascribed to the want of sufficient heat. orderd that the fire be made strong
enough next day for repeating the Expt. (Dogs skin cut & sticht)
snake stone) English vipers not mortall.)
There were made two expts. of breaking wood the one of them was /with/ a cylinder of Pear
tree wood of 1/4 inch diameter which the weight being hung at 1 1/2 inch off
was broken transversly by 6 1/2 pounds & the weight of the scale being 5 pounds
in all 11 1/2 pounds. perpendicular wth. 183 pounds. the other was with a like
Cylinder of wainscote broken transversly with 7ll. & the weight of the scale 5ll
in all 12 pounds perpendicularly 10th 173ll. mr. Hooke was put in mind
of the Expt. formerly by him proposed of Rendring wood hard & tough by
Boyling it in tarr. mr. Howard suggested that this expt. might be tryd vpon
willows (. . . the secretary brought in & Deliuer to mr Ball for Dr. Cotton &
to Dr. crone for Dr. Power . the paper that conteines the ways of Discoue
ring the account vpon which the weight of bodys differ aboue and vnder ground
(about fulminans) mr. Hooke proposed that a certaine Instrument by
him divised might be made to try refractions in, whether they hold by Sines.
Iune 22. 1664 (Dr. Pell has comented vpon Gellebrands tract of the variation of the variation
asserted it hard to Draw an astronomicall meridian) The operator Reported that the Diuer had been
vnder water wth the new Instrument a pretty good while but that he wanted some fitt
glasses for his Eyes mr. Hooke promised to prepare a p' of conuenient spectacles for
that purpose. (The Expt. of a glasse cane with water & a little violl in it was
made wth successe. the water as the expt was orderd and is set down in the notes of
may 11th 1664 shrinking into Lesse room and the Air expanding it self soe as to
Buoy vp the Little glasse and an infinite number of small bubbles appearing
about the glasse pipe which as the water coold swelled bigger. orderd that this
Expt. be repeated the next Day. There was seuerall Expts. made of breaking beech
wood, by breaking diuers peeces thereof one being 1/4 inch diameter & 1 1/2 inch long
was broken horizontally wth 24ll. another of 1/2 inch diam: & 3 inch long was broke
horizontally with 74ll. a 3d. of 1/4 inch diameter & 6 inches long broken ho
rizontally wth. 37ll. (mr.Packer about the strength of wood according to the time of
cutting.) Sr. W Petty about knee timber) Expts. for next Day. - The celerity of falling
bodys by mr. Hooks new instrument to be tryd from mr wilsons Room. 3ly. to cutt the
steel case wherein powder Expt was formerly tryed in a good fire wthout Report to see
what is become of the powder. Orderd that the Instrument proposed by mr Hook
for measuring refractions be made wth all speed.
Iune 29. 1664. Willis's book de Cerebo) Croon chickens choked) Dead cantharides) brough in
by Sr. R moray kept 3 years couerd in which were found seuerall liuing flys supposed to haue been
bred from the corrupted cantharides) mr. Hooke to to Recommended to mr Hooke to look vpon
the flys with his microscope. Dr. Godderd moued that mr Hooke might be Desired to view
a vipers tooth in a Microscope and to giue an account of the Obseron. to the Company -

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