In Lotus Eaters and again in Hades, Bloom passes by the same "hazard," or cabstand, and thinks about the horses hitched to the cabs. There is a "cabman's shelter" near this cabstand on Great Brunswick (now Pearse) Street, a major thoroughfare in the SE part of central Dublin. In Eumaeus Bloom and Stephen stop in at another cabman's shelter, this one just north of the Liffey, for a bite to eat and a cup of coffee.
"Hazard" is an Irish term for a cabstand (the first uses cited in the OED are from the 1880s). Its origins are unknown, but must have had something to do with the threats posed to street traffic by all the cabs parked at the curb, constantly coming and going and attracting passengers from all sides.
For an interesting discussion of cabmen's shelters, see Norman Beattie's webpage at www.taxi-l.org/joyce01.htm. According to Beattie, the first such structure was erected in London in 1875, after an influential newspaper publisher, Sir George Armstrong, sent his servant out on a cold January day to secure a cab, and "The servant was a long time returning because the drivers had all abandoned their cabs and retired to the warmth and conviviality of a local pub." Sir George raised funds to build heated shelters nearer the cabstands; the first one was constructed at the stand nearest his house.
The idea was soon picked up by "the Cabmens Shelter Fund, which equipped them with kitchens and employed retired cabbies to operate them. The shelters themselves were usually small green sheds capable of seating about a dozen customers. At their peak there were over 60 of them in London." The shelters charged for food and drink, and anyone who wished could come in off the street and order a meal. No alcohol was served, so in addition to their air of being philanthropic enterprises, the shelters could claim to be promoting abstinence. In Eumaeus, Bloom nurses dislike of the shelters, but he concedes that they "beyond yea or nay did a world of good, shelters such as the present one they were in run on teetotal lines for vagrants at night."
The shelter in Eumaeus is described as "an unpretentious wooden structure," which certainly fits the building in Tindall's photo at right. But Gifford notes that "These coffeehouse shelters were relatively small eightsided buildings, approximately ten feet by fifteen feet" (534). The lack of octagonal shape, as well as the Guinness ad, in Tillyard's photo suggests that the structure held in Joyce's memory may have been replaced by a new one.