At the dawn of the nineteenth century numerous debates took place on the development of capitalist agriculture and the ways of making as much profit as possible from farm land. Until now this subject has hardly been examined and is unique in that it pertains to the economic history of agriculture, the history of agronomy and the history of managerial thinking. This article aims to highlight the usage of double-entry accounting for agronomic experiments in the first half of the nineteenth century, as well as the significance of the results and the way these were debated. Our aim is to present the authors' reasons and the role played by bookkeeping in the construction of economically rational knowledge and reasoning. Thus we will bring to light two mechanisms which are common to this accounting quantification drive: data tabulation and the inclusion of data in balance sheets, making it possible to compare inputs and outputs in production processes.