A directory of Canada published by Lovell in 1851, compiled by W. S. Mackay, says Thorold had a population of about 1,000 and was connected by a stage line, the fare charged being 1s.3d. (1 shilling, 3 pennies) The following list of business houses is given as being in existence at that time:
- William Cowan and James Parke, Welland Canal flour mills
- James Gibson, Niagara flour mills
- William B. Hendershot, general merchant
- Jacob Keefer, commissioner and conveyancer
- George Keefer, flouring mills
- Peter Keefer, postmaster and clerk of division court
- Henry Rolls, M.D.
- William H. Ward, saw and planing mills and machinist
- Thomas Abbott, shoemaker
- Allen & Campbell, blacksmiths
- Alexander Anderson, grocer
- George Apple, shoemaker
- Lewis A. Ball, attorney-at-law
- John Batten, butcher
- William Beatty, tanner
- Richard Birbeck, tinsmith
- William Butler, Welland Hotel
- Sylvester Carrol, merchant
- Edward Carter, mason
- John H. Casper, cooper
- Charles Cockburn, bailiff
- Cleveland & Shroud, Exchange hotel
- Isabella Dorris, Farmers’ inn
- Patrick Donaghue, butcher
- Robert Dougan, merchant
- Rev. Mr. Evans, Methodist
- Alexander Fair, cooper
- William T. Fish, merchant
- Fisher & McDonald, carriage-makers
- Rev. Thomas B. Fuller, Church of England
- William N. Gardner, grocer
- Joseph Gase, Elgin flour mills
- W. Gordon, shoemaker
- John Grant, apothecary
- Charles Gisso, saddler
- John Grenville, carriage-maker
- Simeon Henderson, mason
- J.B.J. Hilton, corn-broom maker
- Henry Hoover, cooper
- Robert Ironsides, M.D.
- W. James, merchant and baker
- Hugh James, carpenter
- William Keel, butcher
- Rial McArthur, recess
- Daniel McKenzie, cooper
- George McKonachie, blacksmith
- John McDonald, tailor
- Joseph McIntyre, cabinet-maker
- Hugh McMahon, shoemaker
- Robert Martin, British American hotel
- John Morley, ploughmaker
- James Munro & Co., merchants
- John Patrick, baker
- William Paulding, tailor
- Robert Pew, schoolteacher
- Sylvester Preston, chairmaker
- William Ramsay, Temperance hotel, pottery and corporation clerk
- John L. Ranney, Welland Canal Mills
- Charles Rogers, butcher
- Robert Smith, shoemaker
- Maurice Stark, merchant tailor
- Peter H. Swartz, batter
- Joseph Trew, shoemaker
- James Turney, grocer
- William Ward, carpenter
- Thomas Waters, auctioneer
- James Weeks, saddler
- Alexander Winslow, British hotel
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