Convert from cape inch to shaftment [ancient]

Unit Definition (cape inch)
The cape inch is another traditional South African unit for distance. There are 12 cape inches in a cape foot. The Cape foot equals 12.396 English inches, 1.0330 English foot, or 31.4858 centimeters.

Unit Definition (shaftment [ancient])
A shaftment, when used as a unit of length, is usually six inches or two palms, i.e. 15.24 cm (for the international inch). It is thought to be the distance from the tip of the outstretched thumb to the other side of the palm.In English this unit has mostly fallen out of use, as do others based on the human arm: digit (1/8 shaftment), finger (7/48 shaftment), palm (½ shaftment) hand (2/3 shaftment), span (1½ shaftments), cubit (3 shaftments) and ell (7½ shaftments).