GUIANA, BRITISII (Fr. Guyane, Sp. Guayana, Port. Guiana), a section of the extensive tract forming the north-eastern portion of South America, lying between 8° 40' n. and 3' 30' s., and between the meridians of 50° and 68° west. The greatest leterth of this tract. from cape North to the confluence of the river Xie with the river Negro, is calculated at 1090 m.; its greatest breadth, between Punta Barima, at the embouchure of the river Orinoco, end the confluence of the river Negro with the river Amazon, at 710 miles. It is at present politically divided in Venezuelan, British, Dutch, French, and Brazilian Guiana. The name Guiana is usually supposed to have been applied by the Dutch to the whole country from the name of a small river Wai-ini, a tributary of the Orinoco, on which stands a small town, called Guayana Vicija.
The limits of the British possessions have never yet been accurately determined. If we adopt the idea of sir Robert Schomburgk, the latest authority upon the subject, and assume the natural indications to be the proper guide to the geographical boundaries, we shall include all the regions drained by the waters falling into the river Essequibo; and taking the river Corentyn as the acknowledged line of demarkation between 13ritish and Dutch Guiana, we arrive at an area of 76,000 sq.m. a territory much larger than England and Wales. If, on the other hand, the claims of the Venezuelan and Brazilian governments respectively, are to be admitted, the British portion will be reduced to something above 12,000 m., and become the smallest of the European colonies iu this region.
The coast-line of the British territory consists of an alluvial flat, composed of a blue clay impregnated with marine salts, ea mixed with decayed vegetable matter, which, in its decomposed state, forms a rich and highly productive soil. The inland depth of this fertile coast varies from 10 to 40 m., where it is bounded by a range of sand-lulls, varying in height from 30 to 120 feet. In the fifth parallel n. lat. occurs a chain of mountains composed of granite, gneiss, and trappean rocks, with their various modifi cations, and it has been conjectured that it was the ancient boundary of the Atlantic ocean. A peculiar feature of the interior is the savannas extending between the rivers
Demerara and Corentyn, and at the river Bcrbice closely approaching the sea-shore. There is another series of such savannas further inland, and the geological structure of the region indicates that it was once the bed of an inland lake, which, by some great elemental disturbance, burst its barriers, and forced for its waters a passage to the Atlantic. This supposition may throw light upon the origin of the tradition of the White sea and the city of the gold-besprinkled 3Ianoa, which inflamed the ardor of the chivalric Raleigh, and led him to the pursuit of those discoveries by which his name has been immortalized.
The fluvial system of British Guiana consists mainly of four great and seven smaller streams, the whole of the first named and six of the latter pouring their waters directly into the Atlantic. The four great rivers are the Essequibo (q.v), the Demerara (q.v.), the Berbice (q.v.), and the Coreutyn (q.v.). The smaller streams are the Pomeroom the Mortice, and the Wai-ini, between the Orinoco and the Essequibo; the Mahaica, the Malmicony, and the Abany, beteen the Demerara and the Berbice; and the Cauje, which joins the latter immediately before it falls into the ocean. In addition to the fore going, there are numerous creeks of considerable size, formed by the surplus waters of the savannas behind the sea-coast.
All these streams are continually bringing down quantities of detritus; the coast outline is consequently perpetual changes: in one place, the drainage of the estates is blocked up by banks of drift mud; in another, incessant exertion is required to repel the encroachments of the sea.
Climate.—The climate of Guiana is genial and equable, and for a tropical country com paratively healthy. The thermometer ranges from 90° to 75° F., the mean temperature being The barometric pressure—highest, 30.05 in.; lowest, 29.74; mean, 29.916; average rainfall at Georgetown, 100.50 inches.