A Citadel of Ice

In January 1854, 'in the depth of winter, and before the outbreak of the war in the Crimea, Thomas (undertook) a hazardous journey to St Petersburg with a large quantity of money in gold on behalf of a mercantile company.' Thus reads a footnote in the journal kept by the artist Ford Madox Brown. The journey is shrouded in mystery. Why was William Cave Thomas, an artist, chosen for the task? What perils did he face? Who was behind the mission? Whom could he trust? And why was Cave Thomas so eager to leave London and make the arduous journey - a round trip of 3,500 miles - through ice and snow? Was he hungry for adventure, a valiant patriot, or was he merely trying to run away from his own problems?