Sir James Heath was a businessman and politician. He was married four times, at the ages of 29, 72, 75 and 83 y. His last two wives were more than 45 years younger than him (so there's hope for me yet). His only son from his first marriage, Percy Voltelin Heath, used the same design for his bookplate. Percy died during the First World War aged 25y. The bird is a heath cock.