Despite attacks of rheumatic fever, which plagued him for much of his life, D. A. Thomas was no shrinking violet. At college, he rowed and boxed enthusiastically, and his obituary in the "South Wales Daily News" spoke of him being seldom happier than 'when romping with children.' In 1881, D. A. Thomas rescued a boy who fell through the ice on Hirwaun Pond, Aberdare, an act for which he received an award from the Humane Society. In this, and in his later survival of the wreck of the "Lusitania", D. A. Thomas' prowess in swimming, another college sport in which he excelled, holding a medal in the long-dive, stood him in good stead.