June 16, 2003
Here we have removed the hatch that covers the bor. It holds just over 200 gallons of water, which is the amount required for an halakhically kosher mikveh. Water enters the bor at the left side from a pipe which supplies rainwater directly from the yurt's roof. The water flows across the "trough of validation" and into the bor. Requirements for the trough are (1) that it be made of an earthen material, and (2) that it be at least three handbreadths long. In practice "earth" means any mortar composed of earth-derived materials, such as concrete.
The bor connects to the immersion pool through an opening called the "kissing hole", which you can just make out in this photo in the ring of tiles that circle the waterline of the immersion pool. The kissing hole must be at least two finger-breadths in diameter. Ours is somewhat larger than that. The kissing hole provides the connection that enables the water in the bor to validate the water in the larger immersion pool. The hole can be closed while cleaning the pool so that water from the bor remains intact. Before the bor was filled with rainwater, we made sure that it was completely clean and dry, so that it would be filled only with the required amount of naturally collected rainwater in order to ensure its validity.