The banks along the river were formerly occupied with profitable plantations, which were worked by negro slaves, as neither the Spaniards nor the native Indians could endure the climate and the mosquitoes. But when the emancipation of the slaves took place, in 1824, the plantations were abandoned, and have since been so overgrown with tropical vegetation that no traces of their former cultivation exist. The negroes, who have descended from the former slaves, have relapsed into a condition of semi-barbarism, and while they still occupy the old estancias, lead a lazy, shiftless, degraded life, subsisting upon fish and the fruits which grow everywhere in wonderful profusion. Nature provides for them, and no amount of wages can tempt them to work. A few small villages have sprung up along the river, which are trading stations, and furnish some freight for the steamers in the shape of fruit, poultry, eggs, cocoa-nuts, and similar articles, which are attended to by the women of the country. The river itself is a great natural curiosity. It flows almost directly northward, and drains an enormous area of mountains which are constantly covered with snow. The current is as swift as that of the Mississippi, which it resembles, and the water, always muddy, is so full of sediment that one can hear it striking the sides of the boat. The water will not mix with that of the sea, and for fifty miles into the ocean it can be distinguished. In some places it is seven or eight miles wide, at others it is scarcely more than a hundred yards, where it has cut its way through the rolling earth. The channel, which has never been cleared, is full of treacherous bars and snags, which are continually shifting, and make it necessary to tie up the steamer every night, except in times of high water during the rainy season. The mosquitoes are monumental in size, and at some seasons of the year, when the winds are strong and blow them from the jungles, it is almost impossible to endure them. The officers and deck hands of the boat all wear thick veils over their faces, and heavy buckskin gloves, awake or asleep; and the passengers, unless similarly protected, are subject to the most intense torment. Often the swarms are so thick that they obscure the sky, and the sound of humming is so loud that it resembles the murmur of an approaching storm. [Illustration: COLOMBIAN ’GATORS.]