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Show 88 A rldit ionall{otfs. '"l"'l 'f 0 1 111ake a dot with ink in the centre of a circle of red si lk JUS 1 J l ~ ' • · 1 the size of 't letter-wafer, and place it on a sheet of wh1tc paper, an<1 look on it for a minute without moving your eyes; anti then gently turn them on the wbitc pap r in its vicinity, or gently close them, .and hold oue hand an inch or two before them, to prevent too much l1gl.1 t from passing throu;rh the eyelid , a ircular spot of_ pal.c green "1ll he seen 011 the "hite paper, or in the clo~ed eye ; w]ucb 1s c~ll ~d the ocular spectrum of rhe red silk, and i" formed ~s Dr. l~arw1n ..,1.10\VS by the pandiculation or stretching of the ~ne ~bnt ,, wlnch comshtu~c the extremities of the optic nerve, in a c!Jr ·ctwn co 1tn .• ry to th~t, m which they have been excited by previously ),~ok iu g at a hu~lillOUS object, till they become fatigLLed; li_kc the y.awm.ng or stretdHng of the laro·er muscles after acting long m one du·ectJ on . If :t this time the eye, fatigued by looking lono- at. the centre of the rerl silk, be turned on paper previou ly coloured w1tb pale gr ·en; ·the circular spot or ocular spectrum w]ll appear of a m. U<.'~1 d<trl~er oTeen; as now the irritation from the pale green paper comc1des w1th · ~he pale gr en spectrum remaining i.n the eye,. and thus excites those fibres of the retina into stronger actwn; on tlus account some colours are seen more distinctly, and consequently more ag reeably after others; or when placed in the vicinity of others; thus if orange-coloured letters are painted on a blue ground, they may be read at as great distance as black on white, perhaps at a greater. The colours, which are thus mo~e disti11ct when seen in succession are called opposite colours by Sir Isaac N cwton in his optics, Book I. Part 2, and may be ea. ily discovered by any one, by the method above described; that is by laying a coloured circle of paper or silk on a sheet of white paper, and in pecting it some time with steady eyes, and then either gently closing them, or removing them ?n another part of the white paper, and the ocular spectrum or opposite colour becomes isible in the eye. Sir Isaac Newton has observed, that the breadths of the seven primary colours in the sun's image refracted by a prism, are proportioned to the seven musical notes of the gamLLt, or to the intervals of the eight sounds contained in an octave. From this curious coincidence, it has been p.roposecl to produce a Analysis rif Tast~. 89 iuminous music, consisting of successions or combinations of colo 1 . urs, ana ogous to a tune Ill respect to the proportions abov t' d Tl · · 1 e men wne . liS nug 1t be performed by a strong light, made by means of l\1r. Argand's lamps, passing ~hrough coloured glasses, and falling on a ~efined part of the wall, w1th moveable blinds before them, which nnght comm~mica:e. with the keys of a harpsichord, and thus produce at th,.._ er same tune VISible and audib. le music in unison with each othe. I . J." ow as the pleasure we rece1ve from the sensation of melodious notes, independent of musical time, and of the previous associations of a~rceabl: idea wi.th them, must arise from our hearing some pro_ portwns of ~unci ~ft~r others more easily, distinctly, or agreeably; and as there IS a comctdcnce between the proportions of the primary colours, and the primary sounds, if they may be so called; the same Jaws must probably govern the sensations of both. In this circumJstance therefore con ists the sisterhood of Music and Painting; and hence they claim a right to borrow metaphors from each other: musicians to speak of the brilliancy of sounds, and the light and shade of a concerto; and painters of the harmony of colours, and the tone of a picture. This source of pl eas ure received from the melodious succession of colours or of ounds must not be confounded with the pleasure received from the repetition of them explained above, though the repetition, or division of musical notes into bars, so as to produce common or triple time, contributes much to the pleasure of music; but in viewing a fixed landscape nothing like musical time exists; and the plea-. sure received therefore from certain successions of colours must de~ pend only on the more easy or distinct action of the retina in perceive ing some colours after others, or in their vicinity, like the facility or even pleas ure with which we act with contrary muscles in yawning or stretching after having been fatigued with a long previous exertion in the contrary direction. Hence where colour are required to be distinct, those which are opposite to each other, should be brought into succession or vicinity; as red and green, orange and blue, yellow and violet; but where colours are required to intermix imperceptibly, or slide in to each · other, these should not be chosen; as they might by contrast appear N • |