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The Corn Exchange, Mark Lane, was erected in 1828
from designs by Mr. Smith, at an expense of 90,000l., and is a very
fine specimen of time Greek Doric style of architecture. The
wholesale corn trade of the city of London is entirely conducted here; and oats, beans, and all other kinds of grain are sold by
sample in this market, which is held three times a week - viz.
Mondays, Wednesdays, and Fridays; but by far the best attendance is on Mondays.
In addition to those already named are the following :-Spitalfields and the Boroughs Market, for vegetables; the Borough
Hop Market. Newport Market, Clare Market, Oxford Market, and
Grosvenor Market, all for butcher's meat. It may also be added,
that, with some few exceptions, markets are, generally speaking,
on the decline; a circumstance sufficiently explained by time occupation in most of the trading streets of butchers, bakers,
poulterers, greengrocers, and fishmongers.
Mogg's New Picture of London and Visitor's Guide to it Sights, 1844
CORN EXCHANGE, MARK LANE, CITY, projected and opened 1747, enlarged and partly rebuilt in 1827, and reopened June 24th, 1828. The market days are Monday, Wednesday, and Friday, and the hours of business are from 10 to 3; Monday is the principal day. Wheat is paid for in bills at one month, and all other descriptions of corn and grain in bills at two months. The Kentish "hoymen" (distinguished by their sailors' jackets) have stands free of expense, and pay less for rentage and dues than others.
Peter Cunningham, Hand-Book of London, 1850