Herr Ratzel gives an elaborate classification of the forms of African bows, and those who wish to study this subject in detail may be referred to his work. 21 C, which is from a tomb in ancient Egypt. Except that the one bow is strung and the others unstrung, the bow that was made over 2,000 years ago might easily be mistaken for those which were made probably within the last twenty or thirty years. This form varies considerably among different tribes, and probably even with different bows from the same tribe. Thus, some bows are longer and others shorter, some are carefully finished and polished, others are rougher, and even are left with the bark on.
Some tribes use animal sinews for their strings, rattan, rattan, or fibres from other plants.
In some cases a spare length of string is wound round the bow, and ill others the bow is wholly or partially wrapped with snake or lizard skin, or even iron rings. It does not seem possible that any transverse wrapping can be put on with the idea of reinforcing the power of the bow, though Herr Ratzel suggests that this may be the case. The stave is saturated with oil and bent to the required shape over a fire. The string is then finally fixed. As has been already noted, the practice of keeping the bow permanently strung, which Herr Ratzel approves, is, in fact, very detrimental to the cast of the bow.