Burke.
6. Difficult to please or influence; stern; unyielding; obdurate;
unsympathetic; unfeeling; cruel; as, a hard master; a hard heart; hard
words; a hard character.
7. Not easy or agreeable to the taste; harsh; stiff; rigid; ungraceful;
repelling; as, a hard style.
Figures harder than even the marble itself.
Dryden.