The Canon and Canon's Yeoman Timeline and Summary

After the Second Nun's Tale, the Canon and his Yeoman appear, riding hard toward the pilgrims.
When they arrive, the Canon asks for permission to join the company and receives it, conditional on his ability to tell a merry tale.
When the Host asks what the Canon is or does, the Yeoman begins explaining that the two practice alchemy, albeit unsuccessfully.
The Canon becomes angry when he hears the Yeoman divulging his secrets, and leaves the group of pilgrims in a huff.
The Yeoman describes how the success of the alchemical endeavor continues to elude him, while its promise forever entices him.
The Canon's Yeoman tells the 22nd tale.