For the first time the karst research books at the former Ljubljanian Auersperg “Prince’s” library were put at the limelight by using the recently found manuscript catalogue 1668 (transcribed in 1762) and sales catalogues of 1982 and 1983. During the baroque times of Volf Engelbert Auersperg the science of karst was not born yet. The researchers had to wait for another century until the most fundamental facts about karst were proved by Carniolan scientists Hacquet, Gruber, and others. Nonetheless Volf collected several important books about karst with famous authors Aldrovandi, Ferrante Imperato, Johann Joachim Becher, Tommasso Buoni, Jakob Joannes Wenceslaus Dobrzensky de Nigro Ponte, and Athanasius Kircher. The special concern was put on the Count Volf Engelbert and his brother Prince Janez Vajkard interests in karst phenomena and their mutual influence on the younger visitors of their Ljublanian palace, especially Schönleben and Valvasor. Volf and Janez owned several manors at now Slovenian and Croatian karst. Janez Vajkard personally managed the first systematic research of subterranean animals in Postojna cave as a part of his Postojna Manor.