From Mayhew’s London Labour and the London Poor, on the subject of Borough Market (from the wonderful VictorianLondon.org):
…still the costermongers are only a portion of the street-folk. Besides these, there are, as we have seen, many other large classes obtaining their livelihood in the streets. The street musicians, for instance, are said to number 1,000, and the old clothesmen the same. There are supposed to be at the least 500 sellers of water- cresses; 200 coffee-stalls; 300 cats-meat men; 250 balladsingers; 200 play-bill sellers; from 800 to 1,000 bone-grubbers and mud-larks; 1,000 crossing-sweepers; another thousand chimneysweeps, and the same number of turncocks and lamp-lighters; all of whom, together with the street-performers and showmen, tinkers, chair, umbrella, and clock-menders, sellers of bonnet-boxes, toys, stationery, songs, last dying-speeches, tubs, pails, mats, crockery, blacking, lucifers, corn-salves, clothes-pegs, brooms, sweetmeats, razors, dog-collars, dogs, birds, coals, sand, -scavengers, dustmen, and others, make up, it may be fairly assumed, full thirty thousand adults, so that, reckoning men, women, and children, we may truly say that there are upwards of fifty thousand individuals, or about a fortieth-part of the entire population of the metropolis getting their living in the streets.