The Guide du commerce occupies a distinctive place in the French-language literature on accounting. Passed over by most specialists in the history of maritime trade and the slave trade, the manual has never been the subject of a documented historical study. The apparent realism of the examples, the luxury of details and their precision, all bear witness to a deep concern to go beyond a simple apprenticeship in bookkeeping. Promoting itself essentially as un guide du commerce, the volume offers strategic examples for small local businesses, as well as for those engaged in international trade. Yet, the realism also demonstrated the expertise of the author in the eyes of potential purchasers. Inspired by the work of Bottin [2001], we investigate the extent to which the manual reflects real-world practices and provides a faithful glimpse into the socio-economic context of the period. Two additional questions are discussed briefly in our conclusion. First, can the work of Gaignat constitute a source document for the history of la traite negriere? The second entails our early deliberations about the place of this volume in the history of the slave trade itself
