Hints to travellers, scientific and general (1901)
Royal Geographical Society (Great Britain) · London, The Royal Geographical Society · leaf 72
ends an angle of 18°. This may be easily checked by spanning round the horizon ; twenty spans make the circuit. It is at all times well to know the length of the different joints of the limbs. Suppose the nail-joint of the forefinger to be 1 inch, the next joint will be II inches, the next 2… … the wrist would be only 7 inches. The span with thumb and forefinger would be 8 inches, and with the thumb and any of the other three 9 inches, or equal to the length of the foot ; from the wrist to the elbow would be 10 inches, and from elbow to forefinger 17 inches, and from collar-bone to…
