The bookplate of Theodore Radford Forrester Thomson (Thomson Armorial) is on sale at eBay.
Potent Argent and Azure on a bend Sable a mullet between two stags’ heads cabossed Or
A gauntleted hand erect in pale holding a flaming torch in bend proper
Above the Crest: Acquanimitas (With Even Mind)
Below the Shield: Veritas Praevalebit (Truth Will Prevail)
He was the youngest son of Rev. Prof. John Radford Thomson. His Arms were matriculated in the Lyon Register in 1923. His bother, Rev. Canon Clement Reynolds Thomas, matriculated Arms in 1924 (Potent Argent and Azure on a bend Sable two stags’ heads cabossed Or) and his cousin, Charles Sheldon Thomson, also matriculated Arms in 1923 (Potent Argent and Azure on a bend engrailed Sable two stags’ heads cabossed Or). These are also noted in Arthur C Fox-Davies’ Armorial Families (1929 Edition).
More family details can be viewed online at Thomson & Forrester of Corstorphine Pedigree.