Chapter 38

_The texture of _Muscovy_ Glass; 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 Glass. Thirdly, by blowing Glass 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, Brass, 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 _homogeniety_ 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 Glass 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 Assertions: 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 Shell._

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 _Phænomena_ 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 hoar 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 constitution 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 _Phænomena_ 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 shells, &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 Stalks 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 _Phænomena_ 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 multitudes 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, Spunk, &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 Sea-weed.

_From the curiously shap’d Surface of this Sea-weed, and some others, is conjectured the possibility of multitudes 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 description of it out of _Parkinson_: an Experiment made of it: a description, and some conjectures at the cause of the _Phænomena_._

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-glass.

_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._

Observ. 31. Of Purslane Seeds.

_A description of these and many other Seeds._

Observ. 32. Of Hair.

_The description of several sorts of Hair; their Figures and Textures: the reason of their colours, A description of the texture of the skin, and of Spunk and Sponges: by what passages and pores of the skin transpiration seems to be made. Experiments to prove the porousness of the skin of Vegetables._

Observ. 33. Of the Scales of a Soale.

_A description of their beauteous form._

Observ. 34. Of the Sting of a Bee.

_A description of its shape, mechanisme, and use._

Observ. 35. Of Feathers.

_A description of the shape and curious contexture of Feathers: and some conjectures thereupon._

Obser. 36. Of Peacocks Feathers.

_A description of their curious form and proprieties; with a conjecture at the cause of their variable colours._

Obser. 37. Of the Feet of Flyes, and other Insects.

_A description of their figure, parts, and use; and some considerations thereupon._

Obser. 38. Of the Wings of Flyes.

_After what manner and how swiftly the wings of Insects move. A description of the Pendulums under the wings, and their motion; the shape and structure of the parts of the wing._

Obser. 39. Of the Head of a Fly.

_1. All the face of a Drone-fly is nothing almost but eyes. 2. Those are of two magnitudes. 3. They are Hemispheres, and very reflective and smooth. 4. Some directed towards every quarter. 5. How the fly cleanses them. 6. Their number. 7. Their order: divers particulars observ’d in the dissecting a head. That these are very probably the eyes of the Creature; argued from several Observations and Experiments, that Crabs, Lobsters, Shrimps, seem to be water Insects, and to be framed much like Air Insects. Several Considerations about their manner of vision._

Obser. 40. Of the Teeth of a Snail.

_A brief description of it._

Observ. 41. Of the Eggs of Silk-worms.

_Several Observables about the Eggs of Insects._

Observ. 42. Of a blue Fly.

_A description of its outward and inward parts. Its hardiness to indure freezing, and sleeping in Spirit of wine._

Observ. 43. Of a water Insect.

_A description of its shape, transparency, motion, both internal and progressive, and transformation. A History somewhat _Analogus_ cited out of _Piso_. Several Observations about the various wayes of the generations of Insects: by what means they act so seemingly wisely and prudently. Several Quæries propounded. Postscript, containing a relation of another very odd way of the generation of Insects. An Observation about the fertility of the Earth of our Climate in producing Insects, and of divers other wayes of their generation._

Observ. 44. Of the tufted Gnat.

_Several Observables about Insects, and a more particular description the parts of this Gnat._

Ob. 45. Of the great belly’d Gnat.

_A short description of it._

Obser. 46. Of a white Moth.

_A description of the feathers and wings of this, and several other Insects. Divers Considerations about the wings, and the flying of Insects and Birds._

Obs. 47. Of the Shepherd Spider.

_A description of its Eyes: and the sockets of its long legs: and a Conjecture of the mechanical reason of its fabrick; together with a supposition, that ’tis not unlikely, but Spiders may have the make of their inward parts exactly like a Crab, which may be call’d a water Spider._

Obser. 48. Of the hunting Spider.

_A short description of it; to which is annext an excellent History of it, made by Mr. _Evelyn_. Some further Observations on other Spiders, and their Webs, together with an examination of a white Substance flying up and down in the Air after a Fog._

Obser. 49. Of an Ant.

_That all small Bodies, both Vegetable and Animal, do quickly dry and wither. The best remedy I found to hinder it, and to make the Animal lye still to be observ’d. Several particulars related of the actions of this Creature and a short description of its parts._

Obs. 50. Of the wandring Mite.

_A description of this Creature, and of another very small one, which usually bore it company. A Conjecture at the original of Mites._

Observ. 51. Of a Crab-like Insect.

_A brief description of it._

Observ. 52. Of a Book-worm.

_A description of it; where by the way is inserted a digression, experimentally explicating the _Phænomena_ of Pearl. A consideration of its digestive faculty._

Observ. 53. Of a Flea.

_A short description of it._

Observ. 54. Of a Louse.

_A description of its parts, and some notable circumstances._

Observ. 55. Of Mites.

_The exceeding smalness of some Mites, and their Eggs. A description of the Mites of Cheese: and an intimation of the variety of forms in other Mites, with a Conjecture at the reason._

Ob. 56. Of small Vine-Mites.

_A description of them; a ghess at their original; their exceeding smalness compar’d with that of a Wood-louse, from which they may be suppos’d to come._

Observ. 57. Of Vinegar-worms.

_A description of them, with some considerations on their motions._

Obs. 58. Of the Inflection of the Rays of Light in the Air.

_A short rehearsal of several _Phænomena_. An attempt to explicate them: the supposition founded on two Propositions, both which are indeavoured to be made out by several Experiments, What density and rarity is in respect of refraction: the refraction of Spirit of Wine compared with that of common Water: the refraction of Ice. An Experiment of making an Undulation of the Rays by the mixing of Liquors of differing density. The explication of _inflection_, mechanically and hypothetically: what Bodies have such an inflection. Several Experiments to shew that the Air has this propriety; that it proceeds from the differing density of the Air: that the upper and under part of the Air are of differing density: some Experiments to prove this. A Table of the strength of the spring of the Air, answering to each degree of extension; when first made, and when repeated. Another Experiment of compressing the Air. A Table of the strength of the Air, answering to each compression and expansion; from which the height of the Air may be suppos’d indefinite; to what degree the Air is rarifi’d at any distance above the Surface of the Earth: how, from this, Inflection is inferr’d; and several _Phænomena_ explain’d. That the Air near the Earth is compos’d of parts of differing density; made probable by several Experiments and Observations; how this propriety produces the effects of the waving and dancing of Bodies; and of the twinkling of the Stars. Several _Phænomena_ explicated. Some Quæries added._

1. _Whether this Principle may not be made use of, for perfecting Optick Glasses? What might be hoped from it if it were to be done?_

2. _Whether from this Principle the apparition of some new Stars may not be explicated?_

3. _Whether the height of the Air may be defin’d by it?_

4. _Whether there may not sometimes be so great a disparity of density between the upper and under parts of the Air, as to make a reflecting Surface?_

5. _Whether, if so, this will not explicate the _Phænomena_ of the Clouds. An Experiment to this purpose?_

7. _Whether the Rayes from the top of Mountains are not bended into Curve-lines by inflection? An Argument for it, taken from an Experiment made on St. _Paul_’s Steeple._

8. _Whether the distance of the Planets will not be more difficult to be found? What wayes are most likely to rectifie the distance of the Moon: the way of fitting _Telescopes_ for such Observations. How to make the Observations, and how from them to find the true distance of the Moon at any time. How the distance of the Sun may be found by two Observators. The way by the Dichotomy of the Moon uncertain. That the distance of the Moon may be less then it has been hitherto suppos’d. _Kepler_’s Supposition not so probable: the explication of the _Phænomena_ by another _Hypothesis_._

Observ. 59. Of the fixt Stars.

_Of the multitudes of Stars discoverable by the _Telescope_, and the variety of their magnitudes: 78. Stars distinguisht in the _Pleiades_: that there are degrees of bigness even in the Stars accounted of the same magnitude: the longer the Glasses are, and the bigger apertures they will indure, the more fit they are for these discoveries: that ’tis probable, longer Glasses would yet make greater discoveries. 5. Stars discover’d in the _Galaxie_ of _Orion_’s Sword._

Observ. 60. Of the Moon.

_A description of a Vale in the Moon; what call’d by _Hevelius_ and _Ricciolus_, and how describ’d by them: with what substances the hills of the Moon may be cover’d. A description of the pits of the Moon, and a conjecture at their cause: two Experiments that make it probable, that of the surface of boyl’d Alabaster dust seeming the most likely to be resembled by eruptions of vapours out of the body of the Moon: that Earthquakes seem to be generated much the same way, and their effects seem very similar. An Argument that there may be such variations in the Moon, because greater have been observ’d in the Sun: because the substance of the Moon and Earth seem much alike: and because ’tis probable the Moon has a gravitating principle: this is argued from several particulars. The reason why several pits are one within another. The use that may be made of this Instance of a gravity in the Moon._

* * * * *

[1] _Schem._ 2. _Fig._ 1.

[2] Diop. ch. 10. § 9.

[3] _Schem._ 2. _Fig._ 2.

[4] _Schem._ 1.* _Fig._ 3.

[5] _Schem._ 3. _Fig._ 1.

[6] _Schem._ 3. _Fig._ 2.

[7] _Schem._ 4.

[8] _Schem._ 4. _Fig._ 1.

[9] _Schem._ 6. _Fig._ 3.

[10] _Schem._ 6. _Fig._ 3.

[11] _Schem._ 8. _Fig._ 1.

[12] _Schem._ 8. _Fig._ 2.

[13] _Schem._ 9. _Fig._ 1.

[14] See _Schem._ 11. _Fig._ 2.

[15] _Fig._ 1. _Schem._ 36.

[16] _Fig._ 3.