They are sometimes near the Piscina, but are usually on the opposite side of the chancel.
"Our Homeland Churches and How to Study Them"
Sidney Heath
On either side of the nave, near the choir, is a recess in the wall, carved with tabernacle-work, and serving for a Piscina.
"Account of a Tour in Normandy, Vol. II. (of 2)"
Dawson Turner
"This was the Piscina, Mistress Corbet," said the Rector.
"By What Authority?"
Robert Hugh Benson