GULFPORT 427 ctdm: ababic all the British provinces of North Amer- ica, Newfoundland, Canada, New Bruns- wick, Nova Scotia, and Prince Edward Island. It has three communications with the ocean, the Strait of Belle Isle, be- tween Newfoundland and Labrador; the Gulf of Canso, between the island of Cape Breton and the peninsula of Nova Scotia; and a far wider passage than either, with the island of St. Paul in the middle, between Cape Breton and New- foundland; while in the opposite direc- tion it narrows, at the W. end of Anti- costi, into the estuary of the St. Law- rence river. GULFPORT, a city of Mississippi, the county-seat of Harrison co. It is on the Mississippi Sound and on the Louisville and Nashville and the Gulf and Ship Island railroads. The city is a port of entry and has an excellent harbor, acces- sible to large vessels. It has an impor- tant trade in lumber, naval stores, cotton, etc. Its industries include fertilizer works, canning factories, and saw mills. Among the notable buildings are a United States custom house, Gulf Coast Military Academy, and a post office building. Pop. (1910) 6,386; (1920) 8,157. GULF STREAM, a well-defined cur- rent in the Atlantic Ocean. As all ocean currents are so continuous as to be really but one current connected at the two ends, so that the movement of one part is the movement of all, the Gulf stream cannot strictly be said to begin anywhere. It is due to the reflux of the equatorial current. The condensation and super- heating of the last-named current takes place mainly in the Caribbean Sea and the Gulf of Mexico, whence arises the name Gulf stream. Its temperature there is about 50°. It emerges as a de- fined hot current through the Straits of Florida, and courses in a N. E. direction at a little distance from the coast of the United States, so affecting the Bermudas as to make their climate semi-tropical. Between these islands and Halifax the Gulf stream is about 60 miles broad, 100 fathoms deep, and moves at the rate of 3 knots an hour. It is of a deep blue color, in marked contrast to the dull green of the Arctic reflux. The Gulf stream moves in a N. E. direction to- ward Europe. It is generally believed to be through its influence that the W. coast of the European continent is so much milder than the corresponding lati- tudes of America. GULL, the English name of Lams, a genus of natatorial birds. They are wide- ly distributed along the shores of the several seas and oceans, feeding vora- ciously on fish. They breed on rocky headlands, making a rude nest in which they lay from two to four eggs. Many of the species are migratory, and all are powerful of wing, which enables them to fly against a storm. They are slaugh- tered by thousands to provide plumes for ladies' hats. The flesh of the gull is rank and coarse, but that of the young birds is salted for winter use on many N. coasts. The eggs are much sought after for food. Gulls: (1) The sub-family Larinse, one of three into which the fam- ily Laridse is divided. It contains the genus Lestris (Sktia) , in addition to the gulls proper. (2) The family Laridae^ It comprehends not only the gulls, but the terns, petrels, etc. GUM, in anatomy, the soft covering of the dental arches. The gums consist of a dense connective tissue, covered by a scaly and stratified epithelium. GUM, a vegetable secretion, sometimes occurring in intercellular spaces, formed by the separation of the walls of cells; it is viscid, but not oily. The most typi- cal kind of gum is Gum Arabic {q. v.). In pharmacy gum is used as a demulcent to allay the irritation of the mucous membrane, also for suspending heavy powders, when they ai'e given in a liquid. The word is sometimes used synony- mously with the term gumming. Gum from the spruce tree is extensively used as a confection and as a chewing-gum. Doctor's gum is said to be furnished by Rhus vietopinm, a Jamaica plant, to which, as well as to some other plants. Hog gum has been attributed. GUM ARABIC, a gum obtained from the Acacia arabica, which grows abun- dantly in India and Arabia. It is yielded also by A. speciosa in India, A. nilotica and A. seyal in Arabia, A. tor tills and A. ehrenbergiava in ti'opical Africa, A. moUissima and affinis supply a similar gum in Australia. Gum arable can be ob- tained also from VachelUa farnesiana of India, a small tree closely allied to the true acacias; a gum akin to it is derived from Terminalia belerica, a Myrobalan. Gum arable occurs in transparent white tears, which are often colored yellow or brown by impurities. It dissolves in water, and the solution gives a precipi- tate of arabin on the addition of hydro- chloric acid. Gum arable contains about 70 per cent, of arabin, 2Cc;H,oOs-f H:0, and 17 per cent, of water; the rest con- sists of potash and lime, which were com- bined with the arabin. Gum is insoluble in alcohol. By the action of nitric acid it is converted into mucic, saccharic, and oxalic acids.
