IN F. Scott Fitzgerald’s Paris, Dick Diver or someone like him was always stopping at a sidewalk cafe for a few cooling rounds of Vermouth-Cassis.

Gourmandizing journalist A.J. Liebling frequently took shelter behind a Vermouth-Cassis on hot summer days during his 1920s idyll in the City of Light.

This simple Jazz Age drink is also called a Pompier, which means “fireman” in French, and gives you some idea of its cooling properties.

Mix 1 ounce of creme de cassis with 2 ounces of dry Vermouth (I like Noilly Prat) in a glass with ice and a little seltzer. Elie-Arnaud Denoix Creme de Cassis is very good. It costs $17 for a weird, baseball bat-shaped 375-milliliter bottle at Scotto’s Wine Cellar, 318 Court St., in Brooklyn.