Although (or perhaps because) I am still deeply immersed in writing about Macintosh’s experiences in the Caribbean during the 1770s, I cannot resist looking forward to the material that lies ahead. My recent visits to the British Library have allowed me to begin filling in the fascinating details of Macintosh’s counterrevolutionary activities in Switzerland and the levels of secrecy that were required in order to communicate transnationally during the French Revolution.

Alongside the use of sympathetic ink, Macintosh recommended in a memorandum to Charles Jenkinson, then President of the Board of Trade, that a common cypher (above) be used to facilitate safe communication and “to secure agents against surprise”. This period in Macintosh’s life—mysterious by design—is one that I am very much looking forward to tackling and untangling.