Experiments and Considerations Touching Colours (1664)

For I know a Lady of unquestionable Veracity, who having lately, by a desperate fall, receiv'd several hurts, and particularly a considerable one upon a part of her face near he...

And here I must not omit, _Pyrophilus_, to inform You, that we can shew You even in a Mineral Body something that may seem very near of Kin to the Changeable Quality of the Tinc...

I know not, _Pyrophilus_, whether it be worth while to acquaint you with the ways that came into my Thoughts, whereby in some measure to explicate the first of the mention'd way...

_Having promis'd_ (Says our Author)[30] _to say something of that most precious sort of Jewels,_ Carbuncles, _because they are very rarely to be met with, we shall briefly deliv...

That Gold dissolv'd in _Aqua Regia_ ennobles the _Menstruum_ with its own Colour, is a thing that you cannot (_Pyrophilus_,) but have often seen. The Solutions of Mercury in _Aq...

8. Fifthly, And to shew that the Beams that fall on Black Bodies, as they do not Rebound Outwards to the Eye, so they are Reflected towards the Body it self, as the Nature of th...

9. But the same Occasion that invited me to say what I have mention'd concerning the Leaves of Trees, invites me also to give you some account of what happens in Changeable Taff...

You may remember (_Pyrophilus_) that when I mention'd the three sorts of adventitious Colours of Metals, I mention'd them but as the chief, not the only. For there may be other...

And First it seems that the favourers of the Chymicall Theories might have pitcht upon some more proper term, to express the Efficient of Blackness than _Sulphur adust_; for we...

It may afford a considerable Hint (_Pyrophilus_) to him, that would improve the Art of Dying, to know what change of Colours may be produc'd by the three several sorts of Salts...

20. Secondly, A Liquor may alter the Colour of a Body by freeing it from those things that hindred it from appearing in its Genuine Colour; and though this may be said to be rat...

_The forty ninth_ Experiment, _Of making Lakes_ (369.) _A particular example in Turmerick_ (370, 371.) Annotation _the first, That in Precipitations wherein Allum is a Coefficie...

This Experiment may bring some Light to, and receive some from a couple of other Experiments, that I remember I have met with in the ingenious _Gassendus_'s Animadversions upon...

We took a Leaf of Such Foliated Gold as Apothecaries are wont to Gild their Pills with; and with the Edge of a Knife, (lightly moysten'd by drawing it over the Surface of the To...

1. Of greater Moment in the Investigation of the Nature of Colours is the Controversie, Whether those of the Rain-bow, and those that are often seen in Clouds, before the Rising...

It may (_Pyrophilus_) somewhat contribute towards the shewing how much some Colours depend upon the less or greater mixture, and (as it were,) Contemperation of the Light with s...

11. But to return to our Experiments. We may take notice, That the White of an Egg, though in part Transparent, yet by its power of Reflecting some Incident Rays of Light, is in...

That there seems to be a manifest Disparity betwixt Red Liquors, so that some of them may be said to have a Genuine Redness in comparison of others, that have a Yellowish Rednes...

Having in convenient places of the following Treatise, mention'd the Motives, that induc'd me to write it, and the Scope I propos'd to my self in it; I think it superfluous to e...

Greater probability there is, That the Principal Cause (for I would not exclude all concurrent ones) of the Blackness of _Negroes_ is some Peculiar and Seminal Impression, for n...

Chap. 3. _That the Colour of Bodies depends chiefly on the disposition of the Superficial parts, and partly upon the Variety of the Texture of the Object_ (21.) _The former of t...

2. When I apply'd my Self to consider, how the cause of Whiteness might be explan'd by Intelligible and Mechanical Principles, I remembred not to have met with any thing among t...

The Knowledge of the Distinction of Salts which we have propos'd, whereby they are discriminated into _Acid, Volatile,_ or _Salfuginous_ (if I may for Distinction sake so call t...

There is an Experiment, _Pyrophilus_, which though I do not so exactly remember, and though it be somewhat Nice to make, yet I am willing to Acquaint You with, because the thing...

Thus you see, _Pyrophilus_, that though to some I may have seem'd to have lighted on this (50th.) Experiment by chance, and though others may imagine, that to have excogitated i...

Lastly, To comply with the Suspition I had upon the whole Matter, that the chief manifest Change wrought in the Stone, was by Compression of its parts, rather than Incalescence,...