9. Other combinations (for names see [Glossary]) than these are certainly rare, and are perhaps never wanted in English verse, though they are plentiful in prose. (See [Rule 41] and [Glossary].)
§ B. Constitution of Feet
Quality or "quantity" in feet.
10. The quality, or contrast of quality, called "quantity," which fits English syllables for their places as long or short in a foot, is not uniform or constant.
Not necessarily "time,"
11. It does not necessarily depend on the amount of time taken to pronounce the syllable; though there is probably a tendency to lengthen or shorten this time according to the prosodic length or shortness required.
nor vowel "quantity."
12. It does not wholly depend on the usual quantity[26] of the vowel sound in the syllable; for long-sounding vowels are not very seldom shortened, and short-sounding ones are constantly made long.
Accumulated consonants,
13. An accumulation of consonants after the vowel will lengthen it prosodically, but need not necessarily do so.