Isn't aspirated H only a feature in French? I don't think I've heard of it in English, but I'm not really a phonetics bird, just a dabbler. The "h" in "an historical" is mute (though not if you speak slowly, I think - you could say "a hhhistorical memory", or would that be weird?). "Hono(u)r" starts with a mute "h", too, which is why it is an honour to meet you.