The paper discusses the validity of Schurmann's rule-the relation between the moisture content in coal beds and their depth at the given site-using the bituminous coals in the seams of the Czech part of the Upper Silesian Coal Basin as an example. The statistical treatment of analytical data has demonstrated that this relationship between the depth and the moisture content of coals in the seams of the Upper Silesian Coal Basin exists. This study describes the patterns observed in the correlation of the respective parameters and the way in which these patterns can be used to interpret the geological development of coal basins. The patterns are not easy to recognize in all cases. This is particularly evident where low moisture contents are found in bituminous coal from areas with a higher rank of coalification. In contrast, high volatile bituminous coals show a systematic increase in the coefficient of correlation between their moisture content and their depth so that in this case the parameter can be used with greater confidence for modelling the history of coalification in coal basins. Therefore, the moisture content of coal can be used only as a complementary parameter in coal basin studies. (C) 2010 Elsevier B.V. All rights reserved.