Matthias Bel in his work Notitia Hungariae Novae historico-geographica offered a contemporary view of the condition, significance, response and specific features of the Hungarian counties within the Habsburg monarchy. The aim of the present study is a historical-geographical analysis and interpretation of Sections V., VI. and VII. of Paragraph V of the natural history work of Notitia of the Nitra County (1742) in which M. Bel described some water courses of the Váh River Basin: DVDVÁG (Upper Dudváh), BLAWA (Upper Blava) and HOLESCHKA (Holeška). The historical-geographical "probe" into the changing characteristics of these courses over time was realised through a critical commentary on the translation of the original (Latin written) text using literature, old maps, the results of field research and self-knowledge of the given area. The phenomena described by Bel in the above paragraphs naturally do not always correspond with today's level of knowledge. Nevertheless, information about the Upper Dudváh, Upper Blava and Holeška reflects not only the time specific view of specific courses of the examined territory. It also serves as evidence of Bel's methods and creativity.