The picture is of the blackhouse at 3 Ardroil; the following is from Emily Macdonald’s Twenty Years of Hebridean Memories (1939):
When I first came to Lewis [in 1919], there were still a few houses which did not possess a chimney, and in these the fire was in the middle of the living-room floor with a hole immediately above it in the roof, in which was sometimes fixed an old barrel or other cylindrical object to act as a vent. As may be imagined, there was a distinctly smoky atmosphere in these houses, but luckily burning peat has a very pleasant smell, though I admit one can have too much of it. The peat-smoke impregnated thatch and made an excellent dressing for the land, when at the end of a year or so it was removed and a new thatch put on it its place. The houses were all built more or less after the same pattern. The front door opened into a little lobby about three feet square. To the left was the byre where the cattle were housed at night and in cold weather. To the right was the family living room which, as a rule, included in its furniture a bed for the children, and leading out of this apartment was the bedroom.
I found it of great interest to see through the years how the crofters improved their houses as the opportunity to do so came their way. First I would notice a proper chimney and fireplace in one, and then someone else would manage to get an American stove with an oven. Soon someone would collect enough money to build a ‘white’ end on to his house, even though he kept on the old ‘black’ kitchen. The kitchens would be papered all over with a cheery wallpaper, and the hearth would be pipeclayed so spotlessly white that I feel sure it must have been freshly done every day or so. A brightly polished brass rail would be fixed below the mantlepiece, on which anything could be hung to dry or air. Many a time I have sat in front of a blazing peat fire in the house of my friend Mrs Macneill of Carishader while she put my shoes and stockings to dry and plied me with creamy fresh milk and a newly-baked bannock scone.