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as to make a protuberancy appear hollow, & the Right side the left & vice versa, & though we should grant that
there is such a propriety in the parts of the atmosphere of the moon extended ouer and about the Sides of the Mou
taines, soe as to be able to produce such an Inuersion yet that would not suffice to make out the appearances, from
the comming on of the lights & shadows vp ^ In those spotts which Mor Vosius esteems mountaines, but we belieue Cauitys
the middle most part of the Spott being the most prominent, is not first Inlightned as it ought to be according to Mr
Vossius his supposition, but the tops & sides of those circular ridges that encompasse the Spott and are next the sun.
are soe, and the shadow is as it ought to be cast regularly vpon the vper parts of the moon according to the true Rules
of Shadow. Insoemuch that at the beginning the whole middle of the Cauity is perfectly Dark as being ouershadowed by the
Ridge of the Sunny . . side. But as the sun Rises higher and Inlightens the bottom of the cauity. one may in seuerall
of them Discouer, not only diuers other Lesser cauitys or spotts compassed with Ridges as the greater but also Seue
rall small hills or hillocks such as Mor. Vossius would suppose inverted by the refraction of the lunar atmosphere
which doe appear in their true shapes & the lights & shadows properly posited. As to the appearance of Tenariff
Mr. Hooke conceiues it was noe other than the shadow of the pike did darken the surface of the sea towards
the West and likewise that part of the vaporous air that was aboue the Sea, as it may be very often Obserued
when the air is hazy the Radiations between the cloudes & the shadow of the cloudes are plainly Distinuguisht
in the body of the air. And that this was soe seems very probable from the ensuing circumstance in tht History
for vpon of the Sun a Little higher the said atmosphere thickend into cloudes that coverd the surface of the Sea and
the Islands adiacent. Concerning the latter paper of mor Vossius treating of the Burning glasse of Archimedes
Mr. Hooke declared that he could not say whether it were made that way Described by Mor. Vossius or not. But added
he was sure that a speculum made of a parabolick figure would much surpasse one of the same bignesse made vp
of seuerall specular plaines, and that both in the one and the other, the image of the sun would grow bigger & bigger
consequently fainter) according as the focus was further distant from the said Burning glasse. And that therefore this did
not solve that great question about Burning glasse. vizt how to make one of a determinate bignesse that shall burn
at any Distance assigned. --- [Dr. Coxes paper about sea sand for Improvmt of Land. this gaue occasion to
consider of the cause that might render this sea sand more fertilizing than other sand. Mr Hooke intimated that the
sand being made of the sea water, which in processe of time was condensed, it seemd that this sand being not yet
quite fixed, might by being Exposed to the air & mixt with the rain water, be dissolued back againe into Sea-
water & soe fertilize the ground.
[In margin]101.   Mar. 11. Mr. Boyle of Shining flesh Read. This Gaue occasion to some hints for a generall hypothesis.
of explaining the nature of light touching which Mr. Hooke gaue his thoughts as follows, that light was a vibrating or tremulous
motion in the medium (which we thence call pellucid produced from a like motion in the Luminous body, after the same manner
as sound is now generally explained, by a tremulous motion of the medium conueying sound produced therein by a tremulous
motion of the sounding body, and that as there are produced in sounds severall harmonys by proportionate vibrations, soe
there are produced in light seuerall curious & pleasant colours, by the proportionate & harmonious vibrations Mo-
tions of Vibrations intermingled. And that as those of the one are sensated by the core, soe these of the other by the Eye.
Mr. Hooke intimating that he had formerly brought in a paper concerning light, but left it not to be registred,
he was desired to read it again at the next meeting. The same was also desired to haue for the next Day Ready, the
apparatus necessary for the making mr Newtons Expts. formerly alledged by him for evincing the truth of his ^ /new/ theo
-ry of light & colours, especially since Mr Linas had written another Letter from Leige to Mr Oldenburge which Con
teined assertions Directly opposite to those of mr Newton. wch Letter was read bearing date Feb: 25. 1675.
[In margin]102.   Mar. 18. --- Mr. Hooke read a discourse of his concerning the nature & propertys of light, in which were con
teined seuerall new propertys of Light not obserued that he knew of by Optick writers & those were. that there is an
inflection of light differing both from Refraction & Reflection, and seeming to depend upon the vnaequall Density of
the consitutent parts of the ray wherby the light is Dispersed from the place of Condensation, and rarifyed or Gradu
ally Diuerged into a quadrant. 2 that this deflection is made towards the superfices of the opacous body perpen
dicularly. 3ly that in this Deflection of the Rayes, those parts of Diuerged radiation that are deflected by the grea
-test angule from the streight or Direct Radiations are faintest, those that are deflected by the Least are strongest
4 that the Rayes cutting each other in one comon foramen doe not make the angules as verticum aequal 5 that Co
lours may be made without Refraction 6 that the true bignesse of the suns diameter cannot be taken with comon
sights. 7 that the same Rays of light falling vpon the same point of the obiect, will turne into all sorts of colours
only by the various inclination of the Obiect. 8 that colours begin to appear, when two pulses of light are blended so
very well & neer together that the sense takes them for one. --
[In margin]103.   Mar. 25. Grew read of tast. --- mr. Hooke noted that all bodys dissoluble by the saliua are tastable &
consequently all bodys tast lesse that canot be dissolvd by the saliua. He sayd further that euery body that is sapo
-rous hath something peculiar in its structure which gives it a peculiar tast, and that there is probably as
great a variation ^ /in/ of tasts as there is in colours.
[In margin]104.   Ap. 1. noe meet. Apr 8. Sr. R Southwell read a discourse concerning water
[In margin]105.   Ap. 15. Description of Leibnitz watch. beales letter about fruite. Vossius paper read conteining some considera-
tions in Latin vpon Mr Hookes animadversions relating to his former papers about the spotts of the moon & the
Archimedean Burning glasse. mr Hook said that a good obseruer would see that the tops and sides of the Circular
Ridges that surround the spots of the moon are inlightned gradation. & not all alike and altogether,
which Later should be if Dr. Vossius's hypothesis were true. The same appealed to the company whether Para
bolicall speculums were not better for Burning than such flatt ones as Dr. Voss: insisted on.
[In margin]106.   Ap. 22. Wallis of Grauity Boyle of tasts. 12 Expt relating therto. -- The Curator was put in mind to make tryalls with the quadrant
for which the Society hath been at neer 15 pounds charges. (Vz from this to Oldenb death in 77 he did me all the mischief he could
[In margin]107   Ap. 29. Euelyns discourse of Earth.
[In margin]108.   May 6. Im Gregorys letter [of Fish bladders, a paper [a water p'petuall motio
[In margin]109   May. 13 Evelyn of Earth
[In margin]110   May. 20. Vossius Englisht of seas & winds motion --- The Curator produced his heleoscope which being Directed to the
sun, Rendred by Divers reflections the beemes of the Sun soe weak, that one could look vpon the sun with as Little incon
venience to the eye as vpon the moon.
[In margin]110.   May. 27. Mr Locks letter about Bohemia poison fish [Letter about a swordfish [Lemerys letter about Saliuation --- The
Curator promised to bring in his helioscope perfected and besides that another Expt.

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