I later tested my thermometer (sigh). It read 195°F at boiling point. That means I should have taken my fudge off the heat at 219°F instead of 236°F. Quite a difference.
I just had a brain lapse. My word! My mother gave me a nice stainless steel candy thermometer made by Taylor (Smacking myself in the head!) Sheesh, I definitely have to make this fudge again.
What a tasty treat to make. I did not have an 8 x 8 inch pan so these came out a bit thin.