17. thus--as follows.
of fire--the fiery color of the breastplates answering to
the fire which issued out of their mouths.
of jacinth--literally, "of hyacinth color," the hyacinth of the
ancients answering to our dark blue iris: thus, their dark,
dull-colored breastplates correspond to the smoke out of
their mouths.
brimstone--sulphur-colored: answering to the
brimstone or sulphur out of their mouths.
JFB.
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