To the Editor.
According to The New English Dictionary the singular "billiard" is only used in combination, as billiard ball, club, cue, player, room, sharper, etc. This dictionary, which is the latest authority, treats the word as a noun singular: "billiard," plural "billiards." So according to it every combination of the singular should be written with a hyphen, thus: billiard-ball, billiard-room, billiard-table, and so on.
Latham's Johnson's Dictionary, which has a deservedly high reputation as an authority in respect to English literature, treats the word "billiards" as generally plural, but in the following extracts as singular and adjectival:— "Smooth as is the billiard-ball. "#151;B. Jonson.
"When the ball obeys the stroke of a billiard-stick." —Locke.
Consequently "Billiard-Monthly" is correct; either as billiard is considered a noun singular in combination, or as singular and adjectival.
The use of "pyramid" and "pyramids" is somewhat similar; we say "a game of pyramids," but also "the pyramid-balls."
B.