§ 35. Alliteration in relation to the parts of speech and to the order the order of words. Both alliteration and the whole structure of the alliterative line depend in the first place on the natural or etymological accent of the single words, and next on the syntactical accent which these words bear in their relation to one another in the sentence. Just as only the accented syllable of a single word can take part in the alliteration, so only can those words take part in it which are marked out in the sentence as important and therefore strongly accented.
The relative degree of stress is influenced at times by the rhetorical accent, but generally speaking we find a certain gradation of accent among the accented words depending on their intrinsic and not on their rhetorical importance in building up the sentence.
Two general principles may be laid down: (1) If the syntactical value of the two accented syllables of the hemistich is not equal, then the word which has the stronger accent of the two is chosen to alliterate. In the second hemistich it is always the first accented word (the ‘head stave’), in the first hemistich it is generally the first accented word, though the second accented word may alliterate as well. (2) If the two accented syllables of the section are equal in syntactical value, then the first alliterates, and when double alliteration is allowed the second may also alliterate.
The various grammatical classes of words are treated in regard to the alliteration in the following way:—
Nouns, including adjectives and the infinitives and participles of verbs, have the strongest accent of all words in the sentence. A noun therefore takes precedence over the other parts of speech among which it occurs and has the alliteration, as
nḗ in þā céastre becúman méahte. An. 931.
híre þā Ádam andswárode. Gen. 827.
If two nouns occur in the same hemistich it is always the first which alliterates,
hū̀sa sḗlest. Wæs sēo hwī́l micel. Beow. 146.
lánge hwī́le. Him wæs lī́ffrḗa.Beow. 16.