being not an English diphthong, they are better written as they are
sounded, with only e, economy.

With i, as oil, soil, moil, noisome.

This coalition of letters seems to unite the sounds of the two letters,
as far as two sounds can be united without being destroyed, and
therefore approaches more nearly than any combination in our tongue to
the notion of a diphthong.

With o, as boot, hoot, cooler; oo has the sound of the Italian u.

With u or w, as our, power, flower; but in some words has only the sound of
o long, as in soul, bowl, sow, grow. These different sounds are used to
distinguish different significations: as bow an instrument for shooting;
bow, a depression of the head; sow, the she of a boar; sow, to scatter
seed; bowl, an orbicular body; bowl, a wooden vessel.

Ou is sometimes pronounced like o soft, as court; sometimes like o short,
as cough; sometimes like u close, as could; or u open, as rough, tough,
which use only can teach.

Ou is frequently used in the last syllable of words which in Latin end
in or and are made English, as honour, labour, favour, from honor,
labor, favor.

Some late innovators have ejected the u, without considering that the
last syllable gives the sound neither of or nor ur, but a sound between
them, if not compounded of both; besides that they are probably derived
to us from the French nouns in eur, as honeur, faveur.