TRADES IN LONDON. The last population returns (1841) exhibit the following tradespeople, &c., residing in London 

168,701 domestic servants.
29,780 dressmakers and milliners.
28,574 boot and shoemakers.
21,517 tailors and breechesmakers.
20,417 commercial clerks.
18,321 carpenters and joiners.
16,220 laundrykeepers, washers, and manglers.
13,103 private messengers and errand boys.
11,507 painters, plumbers, and glaziers.
9,110 bakers.
7,973 cabinetmakers and upholsterers.
7,151 silk manufacturers, (all branches).
7,002 seamen.
6,741 bricklayers.
6,716 blacksmiths.
6,618 printers.
6,450 butchers.
5,499 booksellers, bookbinders, and publishers.
4,980 grocers and teadealers.
4,861 tavernkeepers, publicans, and victuallers.
4,290 clock and watchmakers.

Peter Cunningham, Hand-Book of London, 1850

see also Henry Mayhew, Letter XXVI - numbers of destitute artisans