“Often use a steamer cover instead of a rain gauge”: The Improvement of Rainfall and Crop Reports and the Utility of Meteorological Work to the Siamese State, 2430s-2450s

Abstract

This article examines the reporting of “Rai Ngan Namfon Tonkhao,” an account focused on rainfall data, runoff, and rice cultivation, by exploring the benefits that the Siamese state derived from improving the Rai Ngan Namfon Tonkhao reporting during the 2430s-2450s. Additionally, it investigates how these reports reflected the knowledge and understanding of government administrators and operational officers regarding meteorological work and responses to weather conditions. By analyzing the Rai Ngan Namfon Tonkhao and other cultivation reports gathered by the Ministry of Agriculture, this research reveals that in 2436 (1893), the redesign of Rai Ngan Namfon Tonkhao and the distribution of new rain gauges to provinces established a new standard for data recording. This approach enabled the government to obtain more systematically gathered empirical data on rainfall and runoff, as well as detailed information on crop yields and agricultural product prices. These data were used to estimate rice yields, which were directly related to the annual income of both the government and rice traders. Furthermore, the improvement of Rai Ngan Namfon Tonkhao data collection was still one of the efforts to consolidate power within the core of the Siamese state. The central government could monitor and exploit resources from the governed provinces. However, the Rai Ngan Namfon Tonkhao also demonstrated that at that time, the Siamese state still prioritized meteorological data as beneficial for agriculture, irrigation, the rice trade, and tax collection more than laying the groundwork for meteorological data collection for scientific knowledge and utilization in other long-term endeavors.