Late-night drinking is an old tradition in North Beach, a neighborhood made famous by sailors celebrating their return to dry land, and now a group of bar owners there is doing what it can to make sure that custom doesn’t die. Every Tuesday from 9 p.m. until midnight, the bartenders at Comstock Saloon, Txoko, and 15 Romolo choose a classic cocktail, and each offers a fresh rendition at a discounted price. The drink changes from week to week, and the group hopes that other nearby bars will want to get in on the action. Plans are being made to turn the event into a roaming dinner. In the meantime, help keep history alive—go and have a drink. Comstock Saloon, 155 Columbus Ave., 415-617-0071; Txoko, 504 Broadway, 415-500-2744; 15 Romolo, 15 Romolo Pl., 415-398-1359.