[e.] and [i.] and so when they are less stricken, [o.] is produced, but when a little more [u.] or [w.]; but we ought carefully to beware, whilst [o.] or [u.] are pronounced, least the Teeth should be seen; for else a certain kind of a soft e. will be mingled; and instead of oe. or ue. there will be produced o. or u. These Letters belong to the French, au and ou, when nevertheless they are nothing else but Diphthongs, also oe. of the Dutch is our u. but very improperly.

Mixt Vowels are ae. oe. ue. These Characters are peculiar to our Language, and were invented very ingeniously by our Ancients, though our Moderns mostly know not the reason thereof.  Each hath its simple Character, because the Sound which they signifie, is only one, tho’ mixt; for a. o. and u. are so pronounced, that the passage of the Voice, the Tongue and Teeth being conjoyned for to pronounce, e. becomes Straiter, and so e. together with the said Letters, a. o. u. doth constitute but one only, yet a mixt vowel.  The French utter them by ai. eu. and u. and in good truth, badly enough, as any one may see.  The Dutch want [ae]. [oe]. and express them by eu. but [ue]. by u. in no better a way than the French.

Concerning the Diphthongs composed out of these Vowels, and which may be thence compounded, I judge it needless to say much; for they are nothing else in our Language than a more then usual swift Pronunciation of the Component Vowels, yet successive; and thus they differ from the mixt Vowels, but how improper and absurd Diphthongs some Nations have, any one may easily gather from what hath been already said.

The other sort of Letters are Semi-Vowels, which are therefore so called, because that they be formed indeed out of a Sounding Breath or Voice, but such as in its progress is much broken.  They are, as I said, either Nasalls, or such as are pronounced through that open passage, by which the Nose opens into the Hollow of the Mouth:  Now the Voice is forced to go that way, either when it flows to the Lips shut close, and rebounding from thence, is formed into [m;] or when the Tip of the Tongue is so applied to the roof of the Mouth, and to the upper Teeth, the Voice is made to rebound through the Nostrils, and so [n] becomes formed; or lastly, when together with the hinder part of the Tongue, the Voice being applied to the Roof, is so straitned that there is no Egress left open for it, but through the Nose, and so [n] is formed; which is a Sound, which hath no peculiar Character in any Language, as I know of, yet it differs no less from the rest of the Nasals, (k) is divers from (t) or (p,) if any one desires to try this by himself, let him endeavour to pronounce; having his Nose held close with his Fingers, one of these three Letters, and he will not be able to do it.