1825 - Joseph Armstrong (d. 1851) sets up business at 261 Deansgate, Manchester as jeweller and silversmith, shop known locally as the old Deanery, was later renumbered as 88.
1828 - married Sarah Booth and had three sons: Thomas, George and Alfred. .
by 1851 - Joseph brought his elder sons into the business. Thomas had already been managing the firm for some years. Thomas, who had
presumably been apprenticed to an optician, expanded the business to include the manufacture of spectacles and optical instruments.
1868 - Thomas took his brother, George Booth, into partnership and changed the company's name to Thomas Armstrong & Brother.
1965 - taken over by Harrisons Opticians. By this time, the firm had branches in Manchester on Oxford Street and Nelson Street (next to the Eye Hospital), on the Downs in Altrincham and on Bold Street in Liverpool.
1968 - The Harrison group was taken over by Dollond & Aitchison.