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Pressed Blue: pressed blue Glass.—The Sandwich Glass Company, founded by Deming Jarves (1790-1869),improved the process for making pressed blue gla; first made a little earlier in Europe and in 18; by the New England Gems Company in Car bridge, Mass. Along with large quantities mold-blown tableware, the Sandwich factoi started (1827) to make pressed blue glass with fine stippled background, now known as Lacy San< wich and probably inspired by that used on 18i century engraved glass of the Low Countrie Mass production of pressed blue glass tablewares fo lowed. Here originated some of the earlie patterns. The glass factories of Pittsburgh als produced pattern glass almost as soon, and coi tinued to make it until the beginning of the 20t century.
BLUES
Prussian blue—A strong tinting blue, very dark with a greenish cast. Good for producing brilliant greens when combined with yellow.
Cobalt blue—A strong blue with a reddish cast. Good for mixing.
Cerulean blue—A strong blue with a greenish cast.
Ultramarine—Sometimes called French blue. It has a reddish cast and makes a beautiful purple when mixed with alizarin crimson.
Because Clerk Maxwell added red, green, and blue light together, this technique is called additive. An equal addition of the three colors forms white; red and green add to form yellow; red and blue, magenta; green and blue, the blue-green known by photographers as cyan. It is important to bear in mind that this theory holds true only for colored light; the mixture of pigments is another matter. |
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