Kogan and Trahtman [2003. The moisture from the air as water resource in arid region: hopes, doubts and facts. Journal of Arid Environments 53, 231¿240] analysed the functioning of a passive dew condenser built by F.I. Zibold in 1912 in Feodosia, and proposed a model to explain how thousands of litres of condensed water might be generated per day based on Zibold's design. In a previous publication, some of the present co-authors explained why it was not possible to obtain high water yields with Zibold-style dew condensers and that Zibold was apparently unaware that the stone heaps in Feodosia were in fact ancient Scythian and Greek tombs. Kogan and Trahtman  take issue with our findings, thus the reason for this comment.