The TRC also has a ball of linen thread, dating to the 1920s to the 1940s, with inside one of them a card roll and inside the card roll one of these pattern slips. It seems that these pattern slips were included in the balls as some sort of advertisement and as a form of inspiration for crochet or embroidery, and an encouragement to buy more DMC materials.
Printed pattern for three different alphabets, inserted into a ball of thread (TRC 2021.0775h and i). DMC, 1920s-1940s.
See a TRC blog by Gillian Vogelsang of 23 March 2021, Pattern sheets for crochet and embroidery, rolled up in DMC balls of thread.
See the TRC catalogue, acc. nos TRC 2020.3566, TRC 2020.3567, TRC 2020.3568, TRC 2020.3569, TRC 2020.3570, and for the ball of thread: TRC 2021.0775h and TRC 2021.0775i.
WV, 19 June 2021.