Posen, “Die Mikwe,” p. 4. The recently opened Freeman Center for Jewish Life at Duke University has considered several proposals for installing a mikvehin its basement. As a member of both the Board of Trustees and a supervisory committee on this project, I can report that we have been in contact with several Orthodox rabbis and architects specializing in systems that depend on rainwater for a supply of pure water. Such rooftop collecting systems for mikva’ot today are somewhat complex but nonetheless predominate in the industry, as they have since late antiquity. So long as no vessel interrupts the flow of water from its point of origin to the mikveh, it is acceptable. As we have noted above, however, a reservoir or storage tank for rainwater would be the preferred way living water is stored. From there to the mikveh its flow may not be interrupted. The transport system in such an instance is called a hamshakah. At the end of a ceramic pipe there would be a small trough or hole to connect the reservoir to the mikveh. Springwater and melted ice or snow could also be used in such a system.