Thanks, Elizabeth K - I was going to post about this too. I was struck by this during a GR of MP (I've linked one of my posts about it below). However, I'm confused why a man would be considered to grow "blacker" with age - most people grow lighter-coloured with age, IMO! However, perhaps JA found him more weather-beaten and tanned, and therefore "blacker". In any case, this use of the word "black" does not seem to have been a compliment! (Any further clarification welcome.:-)