Indian Linguistic Families of America, North of Mexico
(3) Where many peoples, each few in number, are thrown together, an intertribal language is developed. To a large extent this is gesture speech; but to a limited extent useful and important words are adopted by various tribes, and out of this material an intertribal "jargon" is established. Travelers and all others who do not thoroughly study a language are far more likely to acquire this jargon speech than the real speech of the people; and the tendency to base relationship upon such jargons has led to confusion.
(4) This tendency to the establishment of intertribal jargons was greatly accelerated on the advent of the white man, for thereby many tribes were pushed from their ancestral homes and tribes were mixed with tribes. As a result, new relations and new industries, especially of trade, were established, and the new associations of tribe wi