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 _[ä]._
_[ö]._ and express them by _eu._ but _[ü]._ 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,