In giving directions, these people — in fact, the lower classes of Mexicans generally — are also in the habit of using very odd gesticulations, altogether peculiar to themselves. Instead of pointing with their hands and fingers, they generally employ the mouth, which is done by thrusting out the lips in the direction of the spot, or object, which the inquirer wishes to find out — accompanied by aqui or alli esta. This habit of substituting labial gestures for the usual mode of indicating, has grown from the use of the sarape, which keeps their hands and arms perpetually confined.
Commerce of the Prairies (1831–1839), Chapter 19 - Ponds and Buffalo Wallows — The Texans