CaFipers

A kind of compa es with curved legs for measuring the diameter of round bodies. # mercury, which is found native as horn quick¬ silver in Bavaria, Bohemia, and Spain. It is of Camel'opard. great value in medicine, being one of the mildest and most frequently used of all the preparations of mercury. It is used for the liver, as an oint¬ ment, and in producing salivation. Cam'eo. by John Eric on, which is in considerable use for light machinery. In its working parts it Cam'era resembles the steam engine, but is operated by It is usually green and leafy, but in such flowers as the anemone is delicate and resembles the petals. Each leaf of the calyx is a sepal. (See Flower.) machinery, which, by the side of its face ora groove on its surface, changes the motion of another piece against which it acts. Cams are used in the pin-machine, the sewing-machine, and others where varied motion is required. made at Cambray in Flanders. Cambric muslin is thin white cotton. animal, which for centuries has been used as a beast of burden or ship of the desert on the it fills with water, and keeps as a store for future Cain/phor. use. Its two long toes rest on a broad, horny cushion, which enables it to walk without sinking in the sand, and its nostrils can be closed at will to shut out the fine dust of the sand-storms. The African or Arabian camel has one hump, and is called the dromedaty. The Bactrian camel of Central Asia has two humps. The hump is not a part of the skeleton, but is a ma of fat which slowly le ens when the animal is on long jour¬ neys and food is scarce, it being consumed as nutriment. The camel is about six feet in height, and not very rapid in speed. It is very useful to the Arab, conveying himself and his belongings on a journey, and yielding him flesh and milk for food, hair for weaving into a covering, and hides for sandals and saddles. Camel hair is used Canal'. for painters’ brushes. A11 Asiatic shrub with shining green leaves and OF COMMON THINGS 29 showy flowers. In China oil is pre ed from its seeds. [Gk. kainelos, camel and pardos,; a leopard.] An old name of the giraffe, arising from the idea that it was an offspring of the camel and the leopard. [Ital.] A precious stone, as an onyx or sardonyx, having a figure carved in relief on the surface. Obscu'ra. [L,.] An optical instrument. In its simplest form it consists of a rectangular box fitted at one end with a lens and at the other end with a plane mirror, inclined at an angle of 450 to the horizon. When the lens is directed to any object, the rays of light, after pa ing through the lens, are reflected from the mirr r, and form an image on a plate of gla at the top of the box, where they may be observed and sketched. Instead of the box it is usual to have a kind of tent surrounded with curtains to keep out the light. There are various forms of the camera now in use for taking photographic neg a¬ tives, the photographic camera being an adapt a¬ tion of the camera obscura, which is fitted at the back for the introduction of a sensitized plate or film, so as to receive the image of an object or scene in front of the lens. [Gk. chamai, on the ground and; melon, an apple.] A bitter herb used as a med i¬ cine. Its flowers have a strong and fragrant smell, with an aromatic taste. Its volatile oil is used as a carminative. A white resinous substance existing in many plants, but mainly obtained from the camphor laurel, grown in China, Formosa, and Japan. The Borneo or Sumatra camphor, highly esteemed in China, is obtained from a lime tree in Sumatra, Borneo, and the Malay Peninsula. Camphor has an aromatic odor and a strong, unpleasant taste, and is soluble in alcohol and oil. Spirits of camphor is camphor di olved in spirit. When this solution is poured into water, the camphor reappears in white flakes. Cam¬ phor is used as a medicine, and enters largely into varnishes used by painters. It is also used to kill moths and other insects among furs or woolen cloths. For a further important use of it see Celluoid. [L,. canal is, a pipe.] A waterway made for boats or ships or for irrigation. The barrier which confines the water is called the weir or guard lock, and the enclosure with gates at each end to raise or lower boats as they pa from one level to 605