Still worth hunting out and reading. Relevant today, written in an accessible style.
The author was an expert on Scottish architectural history.
Unfortunately there is still no current equivalent book on Scottish townscape that is a straightforward introduction to the subject. The development of Scotland's settlements, including vernacular buildings, cannot be simply be implied from texts about England.
A current, more weighty academic tome is:
Stell, G, Shaw, J. & Storrier, S. (eds) (2003) Scotland's Buildings. Scottish Life & Society - a Compendium of Scottish Ethnology. Royal Commission of Ancient & Historical Monuments, National Museum of Scotland & The European Ethnological Research Centre. Tuckwell Press, East Linton.
Scotland's Buildings: 3 (Scottish Life & Society)