The Pictorial Rug by Jane E. Halliwell
After beginning "Tis and Taint", I was able to purchase this book on pictorial rugs. Jane states that these rugs can be hooked in 3 styles: primitive, realistic, or impressionist. Primitive art lacks detail and pays little attention to scale and perspective. The strips used to hook them are usually a 1/4 inch or larger.
Briarwood Folk Art Pattern Inspired by Magdalena Briner Eby
Realism is representing the subject truthfully. It has details, shading, and perspective. Jane says rugs portraying Currier & Ives prints are good examples. These rugs are often hooked in a #2 or #3 strip. (1/16th inch or 3/32 inch).
Impressionism is somewhere between primitive and realistic. Impressionist rugs lean toward realism but lack some detail and are hooked in a #4 or #5 (1/8 inch or 5/32 inch). Using Jane's definitions, I would categorize "Tis and Taint" as an impressionistic design. Most of the strips I've used have been cut in a #4.
From research I was able to find that "Tis and Taint" (no.912) was created and published on July 20, 1978. I still haven't seen a completed rug.