What did mr.uttersons discover when he went to dr.jekylls House

"Dr Jekyll’s house had been in the past a garden till the building was indifferently know as the laboratory or the dissecting-rooms. Now the own tastes of the doctor being rather chemical than anatomical, had changed the destination of the block at the bottom of the garden. The structure was dingy and windowless; the tables laden with a chemical apparatus, the floor strewn with crates and littered with packing straw, and the light falling dimly through the foggy cupola. At the further end, a flight of stairs mounted to a door covered with red baize."