Marimba instrument - What is Marimba

Among the tribes of southern Africa an instrument similar to xylophone holds the chief place in festivals, and is played upon with considerable skill by many native musicians.
Excerpt from: How? or, Spare hours made profitable for boys and girls by Holbrook, KennedyPublished 1887
This piano, called by them "marimba," consists of two bars of wood placed side by side ; in the most southern portions quite straight, but farther north, bent round so as to resemble half the tire of a carriage-wheel ; across these are placed about fifteen wooden keys, each of which is two or three inches broad, and fifteen or eighteen inches long, and their thickness, as in the case of the xylophone, is regulated according to the deepness of the note required.
Each of the keys has a calabash beneath it ; from the upper part of each a portion is cut off to enable them to embrace the bars, and form hollow sounding-boards to the keys, which also are of different sizes, according to the note required ; and little drumsticks, like those spoken of above, elicit the music.
Rapidity of execution seems much admired among them, and the music is pleasant to the ear.
In Angola, the Portuguese use the marimba in their dances.