One of the stories mentions a cavalry attack, but it doesn’t say if it was tank cavalry or horse cavalry. I mention this because in 1939 both Belgium and Poland fielded horse cavalry.
Horses. I don't think the term "cavalry" was used for other than mounted troops (as in armored cavalry or air cavalry) until the era of the horse was dead and gone.
I came across a cavalry related anecdote in a book about Joe Stilwell I am reading that Tainan recommended. In 1938 Stilwell was military attache in China, but after war broke out in Europe he was brought home and promoted to help with the frantic U.S. preparation of the military for war. He spent a brief period at West Point lecturing on the Sino-Japanese war...
...an occasion memorable for his reply to a Cavalry officer's question on the role of the horse in the fighting in China. After a thoughtful pause Twilwell replied, "Good eating, if your're hungry."
Barbara W. Tuchman
Stilwell and the American Experience in China, 1911-45, pg 204.