Micrographia Part 24

Observ. 7. Of Gla.s.s drops.

_Several Experiments made with these small Bodies. The manner of the breaking and flawing of them, explicated by Figures. What other bodies will be flawed much in the same manner: so other tryals, and a description of the Drops themselves: some conjectures at the cause of the _Phaenomena_, indeavoured to be made probable by several Arguments and Experiments. An Experiment of the expansion of Water by heat, and shrinking by cold: the like Proprieties suppos'd in Gla.s.s drops, and what effects proceed from them: the seven Propositions on which the conjectures are grounded.

Experiments to shew, that bodies expand by heat. The manner of making _Thermometers_, and the Instrument for _graduating_ them. The manner of _graduating_ them, and their use: Other Experiments to prove the expansion of bodies by heat. Four experimental Arguments to prove the expansion of Gla.s.s by heat: further prov'd by the Experiment of boyling Alabaster; which is explicated. An explication of the contracting of heated Gla.s.s upon cooling. An explication how the parts of the Gla.s.s become bent by sudden cold, and how kept from extricating themselves by the contignation of the Gla.s.s drop; which is further explicated by another Experiment made with a hollow Gla.s.s ball: the reason of the flying asunder of the parts further explicated: that 'tis probable these bodies may have many flaws, though not visible, and why: how a gradual heating and cooling does put the parts of Gla.s.s, and other hardned bodies, into a looser texture._

Observ. 8. Of Fiery Sparks.

_The occasion and manner of making this Experiment: divers Observations set down in order to the finding out the reasons: some conjectures concerning it, which are endeavoured to be explicated and confirm'd by several Experiments and Reasons: the _Hypothesis_ a little further explicated. Some Observations about the Globular Figure: and an Experiment of reducing the filings of Tin or Lead to exactly round Globules._

Observ. 9. Of Fantastical Colours.

_The texture of _Muscovy_ Gla.s.s; its Figures: what other Bodies are like it: that it exhibits several colours, and how: several Observations and Experiments about those colours: the reason why on this occasion the nature of colours is inquir'd into. A conjecture at the reason of these colours explicated by several Experiments and Reasons: First, by continual cleaving the Body till it become colour'd. Secondly, by producing all kinds of colours with two flat Plates of Gla.s.s. Thirdly, by blowing Gla.s.s so thin in the Lamp, till it produce the same effect. Fourthly, by doing the same with Bubbles of divers other transparent Bodies: the reasons of the colours on nealed Steel, where by the way the causes of the hardning and tempering of Steel, endeavour'd to be shewn and explicated by several Reasons and Experiments: the reason of the colours on Lead, Bra.s.s, Copper, Silver, &c.

other Instances of such colour'd bodies in animal substances: several other distinguishing Observations. _Des Cartes Hypothesis_ of Colours examin'd.

An _Hypothesis_ for the explication of light by motion, indeavoured to be explicated and determined by several Reasons and Experiments: three distinguishing Properties of the motion of light. The distinguishing Properties of a trasparent _Medium_ [that there seems to be no Experiment that proves the Instantaneous motion of light] the manner of the propagation of light through them. Of the _h.o.m.ogeniety_ and _heterogeniety_ of transparent _Mediums_, and what effects they cause on the Rayes of light, explicated by a Figure: an Examination of the refraction of the Rays by a plain Surface, which causes Colours. An Examination of the like effects produced by a spherical Surface: the use that may be made of these Experiments, for the examination of several _Hypotheses_ of Colours. _Des Cartes Hypothesis_ examin'd. Some Difficulties taken notice of in it. What seems most likely to be the cause of colour: that propriety is indeavoured to be shewn in a Gla.s.s ball: that the reflection is not necessary to produce Colours nor a double refraction: the _Hypothesis_ further examined, both in the _pellucid Medium_ and in the Eye. The definitions of Colours; and a further explication and examination of the Proprieties of _laminated_ Bodies; by what means they conduce to the production of Colours._

Observ. 10. Of Metalline Colours.

_That all Colours seem to be caus'd by refraction. An _Hypothesis_ consonant hereunto, explicated by Figures. How several Experiments, of the sudden changing of Colours by Chymical Liquors may be hereby explicated: how many wayes such Chymical Liquors may alter the colours of Bodies.

Objections made against this _Hypothesis_ of two colours only, indeavoured to be answer'd, by several Reasons and Experiments. The reason why some Colours are capable of being diluted, others not: what those are: that probably the particles of most metalline Colours are transparent; for this several Arguments and Observations are recited: how Colours become incapable of diluting, explicated by a Similitude. An Instrument, by which one and the same coloured Liquor at once exhibited all the degrees of colours between the palest yellow and deepest red: as likewise another that exhibited all varieties of blues: several Experiments try'd with these Boxes. An Objection drawn from the nature of Painters colours answered: that diluting and whitening a colour are different operations; as are deepening and blackening: why some may be diluted by grinding, and some other by being tempered with Oyl: several Experiments for the explicating of some former a.s.sertions: why Painters are forced to make use of many colours: what those colours are: and how mixt. The conclusion, that most coloured Bodies seem to consist of transparent particles: that all colours dissoluble in Liquors are capable of diluting: some of mixing, what a strange variety may thereby be produc'd._

Observ. 11. Of the Figures of Sand.

_Of the substances and shapes of common and other Sands: a description of a very small Sh.e.l.l._

Observ. 12. Of Gravel in Urine.

_A description of such Gravel, and some tryals made with it, and conjectures at its cause._

Obser. 13. Of Diamonds in Flints.

_A description and examination of some of them, explicated further by Cornish Diamonds: several Observations about reflection and refraction: and some deductions therefrom; as an explication of whiteness; that the Air has a stronger reflection then Water. How several Bodies may be made transparent: an explication of the _Phaenomena_ of _Oculus Mundi_. Of the regular Geometrical Figures of several Bodies: an hypothetical explication mentioned: the method of prosecuting this inquiry._

Observ. 14. Of frozen Figure.

_The Figures of h.o.a.r Frost, and the Vortices on windows: several Observations on the branched Figures of Urine: the Figures of _Regulus Martis stellatus_, and of Fern. Of the Figures of Snow. Of frozen water._

Observ. 15. Of Kettering Stone.

_A description of the Figure of the Particles, and of the Pores, and of the Contexture. Several Observations and Considerations thereupon: some Conjectures about the _medium_ and propagation of light, and the const.i.tution of fluid and transparent Bodies. Several Experiments to prove the porousness of Marble, and some other Stones. An account of some Experiments to this purpose made on an _Oculus Mundi_: some other Considerations and Experiments about the porousness of Bodies: some other Considerations about the propagation of light and refraction._

Observ. 16. Of Charcoal.

_Of two sort of Pores to be found in all Woods and Vegetables; the shape of them; the number, thickness, manner and use of these Pores. An explication of the _Phaenomena_ of Coals. The manner of charring Wood, or any other body. What part of Wood is combustible. An _Hypothesis_ of fire explicated in twelve particulars, wherein the Action of the Air, as a _Menstruum_ in the dissolution of all sulphureous bodies, is very particularly explicated, and some other Considerations about the Air proposed: the examination of a piece of _Lignum fossile_ sent from _Rome_, and some Conclusions thence deduc'd._

Observ. 17. Of Wood, and other Bodies, petrified.

_Several Observations of divers kinds of these substances. A more particular examination and explication of one very notable piece of petrified Wood; and some Conjectures about the cause of those productions: several Observations made on other petrified Bodies, as sh.e.l.ls, &c. And some probable Conclusions thence deduc'd, about the original cause of those Bodies._

Observ. 18. Of the Pores of Cork, and other Bodies.

_Several Observations and Considerations about the nature of Cork: the number of Pores in a cubical Inch, and several considerations about Pores.

Several Experiments and Observations about the nature of Cork: the Texture and Pores of the Pith of an Elder, and several other Trees: of the Stales of Burdocks, Teasels, Daisies, Carret, Fennel, Ferne, Reeds, &c. of the frothy texture of the Pith of a Feather: some Conjectures about the probability of values in these Pores. Argued also from the _Phaenomena_ of sensible and humble Plant: some Observations on which are inserted._

Observ. 19. Of a Vegetable growing on blighted Leaves.

_Several Observations and Examinations made of them: several Considerations about spontaneous generation arising from the putrefaction of Bodies._

Observ. 20. Of Blew Mould and Mushromes.

_The description of several kinds of Moulds. The method of proceeding in natural Inquiries. Several Considerations about the nature of Mould and Mushromes. 1. That they may be produc'd without seed. 2. That they seem to have none. 3. That Salts, &c. are shap'd into as curious figures without a seed. 4. Of a kind of Mushrome growing in a Candle: A more particular explication of this last sort of Mushromes. 5. Of the figure and manner of the production of petrified Iceicles: several deductions from these Considerations, about the nature of the vegetation of Mould and Mushromes._

Observ. 21. Of Moss.

_The description of several sorts of Mosses; upon this occasion several Conjectures, about the manner of the production of these kinds of Bodies, are hinted, and some of them explicated by a Similitude taken from a piece of Clock-work, The vast difference of the bigness of vegetable Bodies; and the probability that the least may comprehend as curious contrivances as the greatest. Of mult.i.tudes of other Moulds, Mosses, and Mushromes, and other vegetating Principles, in Water, Wood, _&c.

Observ. 22. Of Sponges, and other fibrous Bodies.

_Several Observations and Conjectures about the making of these Bodies, and several Histories out of Authors. Scarce any other Body hath such a texture; the fibrous texture of Leather, s.p.u.n.k, &c. (which are there describ'd) come nearest to it That upon tryal with a piece of Spunge and Oyl the necessity of respiration could not be alter'd._

Observ. 23. Of the Form of Seaweed.

_From the curiously shap'd Surface of this Sea-weed, and some others, is conjectured the possibility of Mult.i.tudes of the like._

Observ. 24. Of the Surfaces of some Leaves.

_The description, 1. Of the bald Surfaces of Leaves. 2. Of the downy Surfaces of several others. 3. Of the gummous exsudation, or small transparent Pearls, discovered with a _Microscope_ in several others. An Instance of all which is afforded in a Rosemary Leaf._

Observ. 25. Of the stinging Points of a Nettle.

_A description of the Needles and several other contrivances in the leaf of a Nettle: how the stinging pain is created: upon this several considerations about poysoning Darts are set down. An Experiment of killing Effs, and Fishes with Salt. Some conjectures at the efficacy of Baths; the use that may be made of injecting into the Veins. A very remarkable History out of _Bellonius_; and some Considerations about staining and dying of Bodies._

Observ. 26. Of Cowage.

_The definition of it out of _Parkinson_: an Experiment made of it: a description, and some conjectures at the cause of the _Phaenomena_._

Observ. 27. Of the Beard of a wild Oat.

_The description of its shape and properties: the manner of making a _Hygroscope_ with it; and a Conjecture at the causes of these motions, and of the motions of the Muscles._

Observ. 28. Of the Seeds of _Venice_ Looking-gla.s.s.

_The description of them._

Obser. 29. Of the Seeds of Time.

_A description of them. A digression about Natures method._

Observ. 30. Of Poppy Seeds.

_The description and use of them._