Loose leaf notes titled rough diary, 41-55, 1941-1954

Records events in date order, with each entry no more than 1 line. Events covered include visits from family, friends, and professional colleagues; births, deaths, and marriages within the family and social circle; information regarding the house and garden at Ravelston Dykes; lectures Thomson has delivered (though the name of the lecture is rarely given); lunch appointments, and theatre productions Thomson has attended.

The diary is written on the reverse of scrap paper, which includes graphs and tables from the Scottish Mental Surveys; timetables for the supervision of teaching practice; printed rules of the Royal Society Club; and part of a typescript article regarding intelligence and how children absorb and recall knowledge.