COMO
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COMPOSITE
Como (ko'mo), Lake, is situated in northern Italy, at the foot of the Alps. It is 30 miles long, and its greatest width is two and one half miles. The fine climate and the beauty of the scenery of its shores have made it the most popular resort of any lake in Italy and its shores are lined with handsome villas.
Comoro (kom'o'ro) Islands or Comores, lie in the Mozambique Channel. They have been French since 1886, and are administered by the governor of Reunion Island, who appoints a resident for Great Comoro and another for Moheli and Anjuan, which with a number of islets make up the group. The total area is about 620 square miles, with a population of 47,000, nearly all Moslem. Each island has its own budget, and all are self-supporting, sugar and vanilla being successfully grown and coffee and cloves under development. An important coaling station is situated here.
Comox. The northern part of Vancouver Island (British Columbia). A part of the opposite mainland is called Comox district. The two contain 4,000,000 acres. The district is very rich in minerals and timber. Considerable fertile land is found between Comox Bay and Campbell River. The Esquimault and Nanaimo Railway will go through the district. Along the deeply indented coast-line the fishing industry is being developed on a large scale. The whole district is very rich in fertile belts, minerals and timber.
Compass (kum*'pas), Magnetic, an instrument for indicating the direction of the magnetic meridian. The importance of this determination lies in the fact that, if we know any one fixed direction, such as this magnetic meridian, it is easy to locate any other direction by the use of a graduated circle. In this way the direction of a line-fence or the course of a vessel may be easily described.
The three parts of a mariner's compass are (i) a freely suspended steel magnet; (2)
a card attached to the magnet and moving freely with it; and (3) a compass-box, in
which the needle and card are so mounted as always to remain level, however the box may be tilted.
The free suspension of the needle is generally obtained by attaching to it a cap of agate or ruby, which rests on a hard, sharp point.
Practically all the compasses now used on ocean-going vessels are of the type devised and patented by Lord Kelvin in 1876. The magnet is built up of eight or ten small magnets placed some distance apart but parallel to each other. Since the greater part of the mass is thus placed at considerable distance from the axis of rotation, the Kelvin needle is very steady.
For many centuries—at least since the time of Chaucer (1391)—the compass-card has been divided into 32 equal angles called points. Each point is evidently equal to n|°. The names of these points are indicated in the accompanying figure.
In the surveyor's compass the needle swings freely over a circle divided into degrees and provided with a pair of sights. When these sights are so placed that the line joining them lies in any desired direction, the end of the compass-needle indicates at once the angle which this desired direction makes with the magnetic meridian.
The origin of the compass is lost in obscurity. About 1200 A. D. it was commonly used on the Syrian coast, and it is said that Marco Polo in 1260 brought the knowledge of this Chinese invention to Europe. Gioja of Amain, Italy, improved the instrument about 1320. Its variation was known long before Columbus noticed it.
Compass=Plants. The ordinary position of a leaf is approximately horizontal. In regions of intense sunlight and dry air, however, certain plants have learned to turn their leaves edgewise. This is called the profile position, and by means of it one edge of the leaf is turned upward toward the most intense light, and thus the leaf avoids too great drying out. The flat surfaces of the leaves thus face the morning and evening rays of light, which are rays of less intensity than those of midday. As a consequence, the leaves point either north or south, and hence such plants were called compass-plants. The rosin-weeds (Silphium) of the prairies and the common prickly lettuce (Lactuca Scariola) of waste grounds everywhere are among the most notable of the compass-plants. The profile habit is common in the dry regions of Australia, giving to their vegetation a very peculiar appearance.
Compos'itae, the greatest family among seed-plants in point of numbers and in rank. They form one tenth to one seventh of the seed-plant vegetation of almost all regions. Among them are the asters, goldenrods, rosin-weeds, sunflowers, chrysanthemums,
