What is a piscina?
A piscina is a stone basin set into the wall beside a church altar, used for washing the priest’s hands and the vessels used at the Eucharist. Its defining feature is the drain: it does not discharge to the sewer but directly into consecrated ground beneath or beside the church, so that traces of wine and water do not enter ordinary waste water. The word comes from the Latin piscina, “fish pond” or “basin”.
Form and position
The piscina is almost always in the south wall of the chancel, to the right of the altar, at roughly waist height. It usually takes the form of a shallow niche with an arch above, worked in stone. The floor of the niche holds a hollowed bowl with a drain hole.
The piscina is often part of a larger group in the chancel wall:
- The sedilia — a row of seat recesses for the priest and his assistants, usually right beside the piscina.
- The credence niche — a recess with a shelf or bracket on which the vessels were set out.
- The aumbry — a lockable recess for storing the sacrament, usually in the north wall instead.
Sometimes there are two bowls under one arch: one for washing the hands, one for rinsing the chalice.
Why it matters to the building historian
In an old church the piscina is a useful clue. It marks where an altar once stood, even if that altar has been gone for centuries — in a side chapel, say, or in a part of the church later remodelled. A blocked-up piscina high in a wall shows where a lost floor level or a suppressed chapel once was.
The stonework itself is worth dating too: the arch form and the mouldings of the niche follow the style of the period in which the chancel was built or altered.
In restoration
- Keep the drain clear. A silted piscina drain leaves rain and condensation standing in the wall, causing salt efflorescence and frost damage.
- No hard cement mortar in or around a stone niche; it traps moisture and drives it into the softer stone. Use lime mortar.
- Record before you finish. Traces of polychromy and tooling in the niche vanish irretrievably under plaster or paint.
Related terms
- Chancel
- Altar
- Niche
- Aumbry
- Natural stone
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