Columbia Encyclopedia

(Encyclopedia) watercolor painting, in its wider sense, refers to all pigments mixed with water rather than with oil and also to the paintings produced by this process; it includes fresco and tempera as well as aqua...

(Encyclopedia)  CE5 Thyroid gland thyroid gland, endocrine gland, situated in the neck, that secretes hormones necessary for growth and proper metabolism. It consists of two lobes connected by a narrow segment ca...

(Encyclopedia) transit, in astronomy, passage of a body across a meridian or passage of a small body across the visible disk of a larger one. (The passage of a large body across a smaller one is called an eclipse or...

(Encyclopedia)  CE5 Lymphatic system lymphatic system lĭmfătˈĭk [key], network of vessels carrying lymph, or tissue-cleansing fluid, from the tissues into the veins of the circulatory system. The lymphatic sy...

(Encyclopedia)  CE5 A. Structure of a bird wing B. Structure of a bat wing wings, flight organs of the bird, the bat, and the insect. Birds' wings are pectoral appendages that are basically the same in skeletal...

(Encyclopedia) projective geometry, branch of geometry concerned with those properties of geometric figures that remain invariant under projection. The basic elements are points, lines, and planes, and the following...

(Encyclopedia) Samoa, chain of volcanic islands in the South Pacific, comprising the independent nation of Samoa (formerly Western Samoa), and E of long. 171° W, the islands of American Samoa, under U.S. control. T...

(Encyclopedia) lava läˈvə [key], molten rock that erupts on the earth's surface, either on land or under the ocean, by a volcano or through a fissure. It solidifies into igneous rock that is also called lava. Bef...

(Encyclopedia) ore, metal-bearing mineral mass that can be profitably mined. Nearly all rock deposits contain some metallic minerals, but in many cases the concentration of metal is too low to justify mining the ore...

(Encyclopedia) Doppler effect, change in the wavelength (or frequency) of energy in the form of waves, e.g., sound or light, as a result of motion of either the source or the receiver of the waves; the effect is nam...