There lived (and still lives, I believe) in the small Yorkshire village of Tarfield a retired doctor, entirely alone except for his servants, in a large house. It is a very delightful house, only--when I stayed there not long ago--it seemed to me that the doctor did not know how to use it. It stands in its own grounds of two or three acres, on the right-hand side of the road to a traveler going north, separated by a row of pollarded limes from the village street, and approached--or, rather, supposed to be approached--by a Charles II. gate of iron-scroll work. I say "supposed to be approached" because the gate is invariably kept locked, and access can only be gained to the house through the side gate from the stable-yard. The grounds were abominably neglected when I saw them; grass was growing on every path, and as fine a crop of weeds surged up amongst the old autumn flowers as ever I have seen. The house, too, was a sad sight. There here two big rooms, one on either side of the little entrance-hall--one a dining-room, the other a sort of drawing-room--and both were dreary and neglected-looking places. In the one the doctor occasionally ate, in the other he never sat except when a rare visitor came to see him, and the little room supposed to be a study at the foot of the stairs in the inner hall that led through the kitchen was hardly any better. I was there, I say, last autumn, and the condition of the place must have been very much the same as that in which it was when Frank came to Tarfield in October. For the fact was that the doctor--who was possessed of decent private means--devoted the whole of his fortune, the whole of his attention, and the whole of his life--such as it was--to the study of toxins upstairs.