I will here prevent the _Readers_ who may object to me in the following Chapter, that this my Doctrin will be always lame, because all Deaf Persons, whom we would teach by the Tongue, Lips, _&c._ will never by their Sight attain unto these motions: But, besides that the Sight doth not give place to the Hearing, as to a quick sensibility, I affirm, that there is no need thereof, if once they have made but any Progress; for even we our selves do very often not hear in Pronunciation those Letters which I call _Consonants_, but we collect them from the _Vowels_ and _Semi-vowels_, commixed together with them: No Man, for Example, shall so pronounce _b. g._ or _d._ as that he may be heard at a hundred Paces distant. And this seems to me to be the principal reason why we can most rarely pronounce or repeat at the first blush, any word spoken in a foreign Language. But before I shall unfold the nature, and manner of forming the _Letters_ in special, I judged that it was not here to be omitted, how that as all the _Letters_, yea also, and the _Vowels_ them-selves, cannot by any means be pronounced, as they are a _Simple Breath_, and not sonorous; for when we, for Example, do whisper somewhat to one in his Ear, so the _Consonants_ also, excepting those which I call _Explosive_, may be pronounced vocally, or with the _Voice_ conjoyned; and there are Nations which pronounce thus, as the _French_ do their _z._ and their _v._ I shall now treat of the _Letters_ especially, and will examine them so, as both the absolute Simplicity of the _German Letters_ may be manifested; and other Nations, from their Mode of Formation, may learn, how they ought to pronounce them; upon this account also, I shall add how improperly some Nations do render the same Letters in their own Language. Now in this Explication I shall observe the same order as I did in the Division of them, where readily it will appear, that _Voice_ and _Breath_ are according to a triple Region of the Mouth, triply figured or formed spontaneously. Therefore the Simple and Uniform _Vowels_ are, _a._ _e._ _i._ _j._ _y._ _o._ _u._ _w._ and are formed after the following manner.