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metrically opposite to it. Thus, blue wilt he found exactly opposite to orange, which wiH be intermediate between ml and yellow; and, in the same way, yellow-green will be found exactly opposite purple-red, etc. Xow, as rod, blue and yellow are the three primaries, and that all other colors are composed of mixtures of these, let us decide which of the many different colors called reds, yellows, and blues wc are to consider as pure, and true primaries. A pure yellow has been decided upon ; chrome-yellow (No. IXuhromate of zinc (cit ron yellow), or light cadmium. A mixture of any two bright primaries will produce a bright secondary, and any admixture of the third primary will make the secondary color produced much duller or blacker. We consider that would bo the purest blue which gave the brightest green with yellow, at the same time that it gave the brightest purple with a red, and it was decided that cobalt blue was the pure primary, which was blue with regard to the yellow chosen. It is obvious that if the blue were a greenish blue, although it might give a very bright green with yellow, it would give but a dull purple with the red. The yellow contained m the blue, and which made it greenish, would blacken or dirty the purple produced, but would not interfere with the brightness of the green. We choose carmine for the primary red as the color which gives the brightest purple with cobalt blue, at the same time that it gave the brightest orange with chrome yellow. Thus we have chronic (Xo. 1), for yellow, cobalt for blue, and madder carmine for red. These are the primaries.

Colored objects appear colored owing to their action on light. This action consists in absorbing one or more of the different colored rays which fall upon it, and reflecting the rest; and it is these reflected rays that gh e the color to the object. Bodies which emit light are called lumiimts, as the sun. Bodies which transmit light, and through which objects can be distinguished, arc called transparent, as water, glass, etc. Bodies which transmit light, and not so as to permit objects to be seen through them, are called tvvmlwcnt, as ground glass, ctc. Bodies which

Univ Calif - Digitized by microsoft absorb or reflect all tbe rays of light, or transmit so few rays that the eye does not pereenc them, arc called «paque, as wood, metal, etc.

What we call a pure white objcct, such as chalk or white paper," appears white bj reflecting all the light which falls upon it, and is therefore precisely the same color as the light which falls upon it. A pure black object is one which alxorhs all the light which falls upon it, and reflects none. Such an object will always appear black, whatever may be the color of the 1 ight w hich lalls upon it. (Jray objects, (pale black), absorb the three primary rays equally, or in equivalent proportions, but not entirely, so that there is a certain portion of the white light reflected unchanged. A pure green absorbs oïl the red, and reflects all the yellow and blue. A pale but pure green absorbs only pari of the red, and reflects the remainder of the red, together with all the jellow and blue. A dull and blackish green is formed by the absorption of all the red, and also part of the blue and yellow, and the reflection of the remainder of the blue and yellow. The same rule will apply in all cases of all other colored objects, except transparent ones. Silks and satins of either color reflect light.

When three colored rays are mixed together in neutralizing proportions, white light is produced. The easiest way of finding what are the equivalent proportions of tho primary colors is this : dhide a circle of paper into three equal parts, by lines drawn from the center to the circumference. Paint one of these spaces with pure yellow, snch as lemon yellow, or the palest chronic yellow, and paint one of the remaining spaces pure but weak blue, with cobalt, and the other space pure but weak red, with madder carmine. Then try, by spinning the card rapidly ou a pivot, whether these colors neutralize each other, and if not, darken that color that is deficient until the gray produced is ncutnd—» that is, of the color of lampblack mixed with white ; and when this is the case, the colors on the three Fpaces will be of tho proper neutralizing strength for equal spaces,

PEN AND PENCIL DRAWING,

by aid cf the transfer process.

cy/l ie art of transferring pictures from one paper to another ,11 is what fevf understand, Alauy have drawings or engravings which they hold as valuable keepsakes, and wish to I preserve copies. The plan of duplicating almost exactly a picture by the method given here, is original with the author of this book, who has many a time found it iluable in getting perfect the outlines of engravings, prints, and 'pictures of various kinds for pen or crayon drawings. Penmen produce \ery fine specimens of pen draw ing, aided by the above process of copying; and although many a, novice in the art of pen drawing exhibits equally as good designs as older professionals, they are, nevertheless, borrowed.

The paper used for transferring purposes is light tea paper, generally found in a tea store, or on sale at paper stores.

We Prepare it as follows : Procure a piece of soft pine or cedar, and bum to a coal, paste one side of the tea paper with it until quite black, and \ on have a neat transfer sheet. (In choosing the wood be sure and get soft white pine). Lay this black paper upon the white, where you wish the drawing to be made, the dark side down; upon this lay the copy, face up, and fasten the whole to the table with thumb tacks, to prevent its moving around and changing the outlines. This done, go over the whole with a tracer made of wood or ivory, with sufficient pressure to carry the lines through to the paper underneath, following every outline of the picture until the whole has been gone over. Lift the tracing paT<er. and you hav e upon the sheet 'oelow the desired

Unnr Carif - Digmzecrby Microsoft &

tuynsfekring.

drawing, which vou now go over with pen or pencil. After this is done, rub the era} on from oil' the picture with your handkerchief, and complete the shi ding with a line pointed steel pen or pencil, keeping the copy before yon. Use Spencerian Artistic Pen, Crow-.pi.il, or Gillott's Xo. 170.

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