376 READINGS IN BIOLOGICAL SCIENCE 



This is the anotto or achiote, and as the orange-red dye or pigment is harm- 

 less and even contains a certain amount of nutriment, it is perfectly adapted 

 to coloring foods. In its raw state it is a vivid red and is used by the Indians 

 for painting their faces and bodies, but when diluted it imparts a deep 

 yellow color. Its principal use is for coloring butter, hence it has become 

 generally known under the trade name of "butter color." 



Formerly our own native trees supplied many world-famous dyes. But- 

 ternut-brown was widely used and became famous as the color of the uni- 

 forms of the Confederate soldiers during our Civil War. But to-day it has 

 no real commercial value, and the same is true of our yellow or quercitron 

 oak which furnishes a wonderful yellow dye. At one time hundreds of 

 tons of the chipped oak bark were exported to Europe, but to-day its use 

 as a dye has been almost forgotten. 



Even when plants have supplied us with wood for our houses and furni- 

 ture and fabrics for our garments, our carpets, our draperies and the up- 

 holstery on our chairs and couches, and other plants have yielded the 

 stains, dyes, and pigments with which to color them, we still need oils, var- 

 nish, and wax with which to finish the woodwork. And when it comes 

 to these important and essential substances we are compelled to rely on 

 plants to supply them. There is no substitute for linseed-oil except other 

 vegetable oils. No one has been able to manufacture a synthetic varnish 

 to compare with those made from copal, coiiri, or other plant gums and 

 saps. Turpentine and resin from pine trees still hold their own against all 

 competitors made from petroleum or other chemicals, while tung oil is 

 the basis of all our finest quick-drying lacquers, enamels, and varnishes. 



It is the same with the various kinds of vegetable wax. Who wouldn't 

 prefer a bayberry wax candle made from the aromatic berries of the sea- 

 side bay berry bush to a paraffin or tallow candle? What would scientists 

 do without oil of cloves for use in microscopy and Canada balsam from 

 the fir trees for mounting their sHdes and cementing the lenses of their 

 instruments? Palm-oil and palm-wax have never given way to synthetic 

 products of the laboratory. And finally there is the oil from the castor- 

 bean plant. No doubt many a youngster wishes the broad-leafed tropical 

 plant had never been discovered, but the thick white oil from the plants' 

 mottled seeds has many other uses besides that of medicine and possesses 

 properties unlike those of any other oil. It never thickens, no matter how 

 cold it may be; it never becomes thin even under the terrific heat of high- 

 speed motors when used as a lubricant, in which respect it exceeds all other 

 oils, and it is practically non-inflammable. But it has one important use 

 which few persons suspect, for it is castor oil that makes sticky fly-paper 

 remain sticky and prevents the combination of resin and gum from dry- 

 ing up. 



To the ladies there are many plants which are of tremendous importance, 



