There can be few books which combine Meiji Japan, Victorian Glasgow, shipbuilding and potatoes, warpped up in a romantic mystery but this one does. The story of Ryōkichi Kawada, a young man sent to study in the shipyards of the Clyde and Jeanie Eadie, a bookshop assistant is told mainly through over 90 letters, sent by Jeanie and discovered a century later.
Although this is the story of an ultimately tragic romance, there is no purple prose. Jeanie's letters are generally matter-of-fact (often no more than short notes, written in snatched free moments) and only occasionally does she mention their feelings and intentions of marriage. It's unfortunate that we only have one side of this conversation - it's apparent from Jeanies responses that Ryōkichi had more time for letter writing and was probably more open.
The author, Andrew Cobbing, is an academic historian, but works well with the scant evidence he has, particularly in fleshing out the political and social backgrounds of both to provide a readable account.
In fact, from a modern reader's viewpoint, one of the biggest problems is that neither Ryōkichi or Jeanie come across as particularly sympathetic, Ryōkichi seemed prone to fits of depression and temper, and Jeanie with her strong religious involvement, somewhat priggish.
Ultimately however, their dreams of marriage came to nothing, and very little is known of Jeanie from here. Ryōkichi however had a prominent career in Japan, eventually retiring to Hokkaido, where he developed a model farm and is credited with introducing the 'Baron Potato', still one of the most popular varieties in Japan.

Today, his farm is a museum, of agricutural equipment, Japan's first motor car and of course Jeanie's letters.

Baron Museum ( )