(To). Having the metre fixed and the last letter of the previous line given, to add a verse beginning with the given letter (of the same metre or not, according to prearrangement) thus:
Dogs with their tongues their wounds do heal(L). Like words congealed in northern air(R).
Regions Caesar never knew (W).
With all a poet's ecstasy(Y).
You may deride my awkward pace, etc. etc.
Sunt quos curriculo pulverem Olympicum(M). Myrtoum pavidus nauta secet mare(E).
Est qui nec veteris pocula Massici(I).
Illum, si proprio condidit horreo(O).
O, et presidium ... (as long as you please).
It would make a Christmas game to cap proper names: as Plato, Otway, Young, Goldsmith, etc., or to cap proverbs, as: “Rome was not built in a day”; “Ye are the salt of the earth”; “Hunger is the best sauce”;
“Example is better than precept”; “Time and tide wait for no man”; etc.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894