Final answer:
The Once-ler knitting in his shop symbolizes the era of handcrafted artisanal products, indicative of pre-industrial craftsmanship and individual labor that is later replaced by mechanized factory production during the Industrial Revolution.
Step-by-step explanation:
When the Once-ler is knitting in his shop, he is representing a precursor to Industrialization that is most akin to handcrafted artisanal products. This activity reflects a period when items were produced by hand, typically within small shops or home settings, prior to the advent of mechanized factory production which defined the Industrial Revolution. This was a time when the making of goods, such as homespun clothing, employed individual craftsmanship - a stark contrast to the later mass production methods introduced by the textile mills and other mechanized means.