of exactly equal force[64] they are always prominently distinguished from the unaccented members of the hemistich, the rhythm of which would be marred by the introduction of an additional beat however slightly marked. Cases in which the two chief beats of the hemistich are not of exactly the same force occur when two accented syllables, either both with chief accent or one with chief and the other with secondary accent, stand in immediate juxtaposition, not separated by an unaccented syllable. The second of these two accented syllables may be a short syllable with chief accent, instead of a long syllable as is the rule. But in either case, whether long or short, this second beat following at once on the first beat is usually uttered with somewhat less force than the first, as can be seen from examples like _gebū́n hǽfdon_, Beow. 117; _tō hā́m fáran_, 121; _mid ǣ́rdǽge_, 126. The second beat rarely predominates over the first. The cause of this variation in the force of the two beats is to be sought in the laws of the syntactical accent. In other respects verse-members with a secondary accent obey the same laws as those with a primary accent. They usually consist of one long syllable, but if a member which has the arsis immediately precedes, a short syllable with a secondary accent may be substituted. Resolution of such verse members is rare, which shows that they are more closely related to the thesis than to the arsis of the hemistich. One unaccented syllable is sufficient to form the thesis (×), but the thesis may also have two or more unaccented syllables (× ×, × × × ..), their number increasing in proportion to their shortness and the ease with which they can be pronounced, provided always that no secondary accent intervenes. All of these unaccented syllables are reckoned together as one thesis, as against the accented syllable or arsis. The single components of such a longer thesis may exhibit a certain gradation of force when compared with one another, but this degree of force must never equal the force with which the arsis is pronounced, though we sometimes find that, owing to the varying character of the syntactical or sentence accent, a monosyllable which in one case stands in the thesis, may in another connexion bear the secondary or even the primary accent.