The philosphical and physical opinions written by Her Excellency the Lady Marchionesse of Newcastle.

Chap. 121. Of Colours.

SOme say colours are made by perturbed or obstructed light, but in my opinion, colours are broken lines of light; for when light is obstructed as being stopped it reflects with double light, those lines returning back like double strings, and if it were perturbed light, like over-agi∣tated air, or troubled and rough waters, the light would be onely thicker, and mudier, having not liberty to move in so level, even, and straight, paralel lines; it is true, those per∣turbed motions may be the cause many times of breaking the light, which broken parts contracting into several figures, or works, causeth several colours, every particular work, being a several colour, and when these several figurative works are mixt, being part of one work, and part of another, the co∣lors are also mixt.

For the several works made of the pieces of light, are that which makes several colours, and not the pieces of light with∣out those works, for if those pieces of light lay scattered and not contracted into several figurative workes, they could, or would not make colours, but if colours are not made by pieces of light, they are made by contracting the straight unbroken lines of light, which contraction turns light into colours, as contractions do water into snow, ice, hail, frost; Now it is to be observed, that it is not onely the contracted motions on the water that make the difference, but being contracted into such or such a figure; for whensoever water is contracted into such a manner of figure, it is snow, if into such a figure it is hail, if in such a figure it is ice, into such a figure frost, and may do so constantly, and eternally, and so when light is contracted into such a figure, it is red, when into such a figure, blue, into such a figure, yellow, into such a figure green, and when it is contracted partly into the figure of red, and partly into the figure of blue, it makes a figure of purple, and if it be contracted partly into the figure of red, and partly into the figure of blue, and partly into the figure of purple, it makes a fourth figure, which is a fourth colour, and so a fift, and so infinites, likewise one and the same figure which is one perfect colour, may vary with each patticular figure, which is each particular colour, and upon what body soever these figures are printed, they take colours, and accor∣ding as the figures differ, the colours are changed, or alter; for it is not the body that they are printed on, or the reflecti∣ons of light, cast upon such bodies that make colours, but such figures made by contracted lines of light, which figura∣tive works give such colours to any thing they can print, or place on, but the reason why I think they are rather broken pieces of light contracted, then contracted streight lines, is, be∣cause they are so lasting, for though some colours will fade

sooner, yet some will last a long time; for whatsoever work is wrought with parts, as I may say, several pieces of thread, is not so apt to undo or ravel out, as that which is but of one piece, unlesse the thread were circular, without ends, but lines of light are paralels, and not circles, as for shadows of colours, in my opinion they are produced after this manner as I said, the figure of blue or the like, which is one perfect colour, and the figure of red which is another perfect co∣lour makes a third figure, which is a mixt colour, likewise blue and yellow makes a different figure, which is a different colour from blue and red, and blue and yellow, makes a dif∣ferent figure, which is a different colour from blue and green, & so we may match figures until we be weary, but whatsoever hath constantly part of one and the same figure, in the several or single compartments of other figures, which are other co∣lours, as blue and green, blue and red, blue and yellow; and the like appears in shadows, by reason one particular figure, or figurative part is the ground-work, which is, the ground colour, which makes all the colours it mixes with, partly of its own complection, and according as there are more or lesse, of that figure, the shadow is fainter or stronger, and according as the contractions are more or lesse, the colours are deeper, or paler; for those figures that are closer contracted, and rougher wrought, are the darkest colours, as neerest to black, and those figures that are loosest, contracted, and finer wrought, ars the the lightest, or palest colours, as being most light, when the parts are loosest, and most at liberty, and the brightest, as the most glorious colours that are made of the purest, and clearest light, which is of the smallest lines of light, as I may say, the finest threaded light, for some lights are thicker then others, by reason their lines are grosser.

Also colours which are broken contracted lines of light, may appear darker, or brighter according to the reflection, of other lights, or rather according to the straight and unbroken lines of light are that cast upon them, likewise some light doth alter the colours that are made by other lights, as some colours appear not by candle-light as by day-light, and the reason is, that several lines of several lights, being grosser, or finer, causeth the colour to appear duller or brighter, and some par∣ticular lights make some colours appear more then others, and some particular lights obscure some particular colours more then others, according as they are further, or neerer off the nature of each other; for though the several figurative works make the several colours, yet it is the lines and pieces of light, that make those figures and works.