author
A little-known early 20th-century writer whose work helped bring the landscapes, history, and daily life of Orkney and Shetland to a wider audience. Best known for co-authoring a compact regional guide, the writing is practical, informed, and full of local interest.

by John George Flett Moodie Heddle, T. Mainland
Very little biographical information about T. Mainland could be confirmed from the sources available during this search. The clearest trace is as co-author, with J. G. F. Moodie Heddle, of Orkney and Shetland, a volume in the Cambridge County Geographies series first published in 1920.
That book focuses on the geography, natural features, settlements, and history of the Orkney and Shetland Islands. From the work itself and its catalog listings, Mainland appears to have been a knowledgeable contributor on the region, writing in a clear, informative style meant for general readers.
Because reliable personal details such as full name, dates, and a fuller life history were not readily confirmed, it's best to remember T. Mainland through the surviving work: a concise portrait of northern Scottish island life from the early twentieth century.