amphibrachic

There can be an infinite amount of discussion of how to “scan” this Frost couplet (and I am sure there are scholars who would disagree with me), but I imagine Frost means both lines to be bouncy (triple – i.e. amphibrachic, dactyllic, anapestic, what have you) tetrameters:

Dipodic Verse : A.E. Stallings : Harriet the Blog : The Poetry Foundation 2007

Even when the beginning of the series is made coincident with the initial phase of the amphibrachic group the rhythmic type slips over into the dactylic, in spite of effort.

Harvard Psychological Studies, Volume 1 Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory. Various 1889

In triple groups the amphibrachic form (in regard to temporal relations only, as no accentuation was introduced) was never heard under natural conditions.

Harvard Psychological Studies, Volume 1 Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory. Various 1889

In the group of triple rhythms next taken up -- the dactylic, the amphibrachic and the anapæstic -- each type presents an increase in the duration of the unit group between the beginning and end of the series, but without any regular curve connecting these terms.

Harvard Psychological Studies, Volume 1 Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory. Various 1889

They have the following values: Dactylic, 10.25; amphibrachic, 12.84; anapæstic, 12.45.

Harvard Psychological Studies, Volume 1 Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory. Various 1889

This is due to the coöperation of two factors, namely, the proximity of the accentual stress, which in no case is separated from this median position by an unaccented element, and the relative difficulty in giving expression to amphibrachic rhythms.

Harvard Psychological Studies, Volume 1 Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory. Various 1889

When the beginning of the series was made to coincide with the initiation of an amphibrachic group, four of those taking part in the investigation succeeded in maintaining this form of apprehension for a time, all but one losing it in the dactylic after a few repetitions; while the remaining two members were unable to hold the amphibrachic form in consciousness at all.

Harvard Psychological Studies, Volume 1 Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory. Various 1889

In the amphibrachic form the average again shows three degrees of intensity, three out of four subjects conforming to the same type, while the fourth reverses the relative values of the first and third intervals.

Harvard Psychological Studies, Volume 1 Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory. Various 1889

In the amphibrachic form the changes manifested by the constituents of the unit group are more obscure.

Harvard Psychological Studies, Volume 1 Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory. Various 1889

The amphibrachic measure begins weakly and ends strongly, and thus approximates, we may say, to the iambic type.

Harvard Psychological Studies, Volume 1 Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory. Various 1889