A small subject indeed, but pertinent to this Woodwork Site
Below you will find photos of “Joiners’ Dogs or Joint Cramps”
The first reference I can find is in the 1897 Catalogue, but they may have been in production before then. They are listed there as #835A, but that number changed to #1897 by 1909. They are listed as being ‘Stamped’, but ‘Strong Forged'[ Item #1898] were also available at a higher price. The ‘Stamped’ variety [shown] were available into the 1959 Catalogue but only the ‘Forged’ were available in 1965 onwards. They were available 1.1/2″– 3.1/2″, but this varied a little over time. Shown here are some 2.1/2″, and they are 5/32″ thick. They did however tend to be prone to bending with hard use, whereas the ‘Forged’ variety were certainly stronger. In the 1959 Catalogue they are named “Joiner’ Dogs”