The laws of the conversion of sounds of the one organ into those of another have not yet been discovered; but the above examples, which are by no means isolated ones, serve to admonish us that the phonetic elements of primitive speech probably had no fixedness.
There is another oddity about some of these consonantal sounds which I may notice in passing. Some of them are not true elementary sounds; they cannot stand alone, but must always have another consonant associated with them. Thus, the labial _B_ is common in Guarani; but it must always be preceded by an _M_. In Nahuatl the liquid _L_ is frequent; but it is the initial of no word in that language. The Nahuas apparently could not pronounce it, unless some other articulate sound preceded it.
Albornoz, in his _Grammar of the Chapanec Tongue_,[342] states that the natives cannot pronounce an initial _B_, _G_, _Y_, or _D_, without uttering an _N_ sound before it.
The third point in the phonology of these tongues to which I alluded is the frequency with which the phonetic elements, as graphically expressed, are inadequate to convey the idea. I may quote a remark by Howse in his _Cree Grammar_, which is true probably of all primitive speech, “Emphasis, accent and modifications of vocal expression; which are inadequately expressed in writing, seem to constitute an essential, perhaps the vital part of Indian language.” In such modifications I include tone, accent, stress, vocal inflection, quantity and pause. These are with much difficulty or not at all includable in a graphic method, and yet are frequently significant. Take the pause or hiatus. I have already mentioned that in Tinné it correlates a whole series of ideas. M. Belcourt, in his Grammar of the Sauteux, an Algonkin dialect, states that the pause may completely change the meaning of a word and place it in another class; it is also essential in that language in the formation of the tenses.[343] This is the case in the Guarani of South America. Montoya illustrates it by the example: _Peru o’u_, Peter ate it; but _Peru ou_, Peter came; quite another thing, you will observe.[344]
The stress laid on a vowel-sound often alters its meaning. In the Sauteux, Belcourt points out that this constitutes the only distinction between the first and second persons in participles. In the Nahuatl this alone distinguishes many plural forms from their singulars; and many similar examples could be cited.