Le 1er février 1864 sortit des presses de la L.M.S. (Société Missionnaire de Londres) à Tananarive un almanach de 24 pages in 12 portant le titre : Ny alimanaka amy ny volana sy andro english sy malagasy hahalalana ny isany nyvolana sy ny isany ny andro amy ny taona 1864, tamy ny taona voalohanynanjakany Rasoheri-manjaka.

Le sous-titre révèle un contenu beaucoup plus ample puisque l'almanach donnera « les phases de la lune, les heures de levers et couchers du soleil, un certain nombre d'événements remarquables concernant Madagascar, ainsi que les noms des personnalités qui ont la charge des affaires du gouvernement à Madagascar ». Analysons tout d'abord de plus près la composition de cet opuscule.

The Malagasy System of astronomy, entirely empirical and unrelated to any scientific ride, was closely associated to an inclusive form ofastrology in keeping with the realities of social, économie and political life.

The publication and circulation in February 1864 by the London Missionary Society of the first almanach containing the Gregorian occidental calendar was thus a revolutionary event. The calendrical part of this almanach eclipsed the astrological framework which had previously organized collective life and private conduct, and it served as a symbol ofa new power relationship. The almanach also placed the représentation of the Malagasy government in a certain perspective. By juxtaposing the powers ofthe Queen and, for the first time, those ofa prime minister against those ofthe English government, it implied that the new régime was based on a constitutional pact. Finally, a séries of historical reminders presented the history of Madagascar as one dominated by ils relations with the Europeans. Reconstructing the various contexts of its publication affords an opportunity to appreciate the missionary goals represented by the almanach as well as those of the indigenous authorities.