Repositorium Sanctae Eucharistiae - Historical Modes of Eucharistic Reservation: The Sacrament Tower

Throughout the course of history there has been more than one method of reserving the Eucharist. In our own time we are especially familiar with the model of a metal or stone tabernacle being integrated onto an altar or altar like structure -- whether a central high altar, the altar of a side chapel or something visually similar to this.  A lesser known historical form of Eucharistic reservation is the the so-called "Sacrament House" or what is frequently often referred to as a "Sacrament Tower."

This method of reservation seems to be particularly in evidence within the late medieval period, specifically concentrated within a northern Europe context where they are  oftencalled "Sacramentstoren" or "Sakramentshäus".

Archdale King has this to say of them in his work, Eucharistic Reservation in the Western Church:

The elaborate stone structure in which the Eucharist is reserved in many of the churches of Germany and the Low Countries, isolated from the altar and normally on the gospel side of the sanctuary, is known as a sacrament house. They were often sculptured in the form of a monumental tower, approached by several steps, and with a railing around, on which candles were placed. Sometimes, also, there were two or more storeys and a space above for a light.

These sacrament houses appeared first in Germany in the fourteenth century (c. 1380), and became increasingly popular both there and in the Low Countries in the two subsequent centuries. It is thought that they originated as a compromise, enabling the faithful to see the Blessed Sacrament or at least the eucharistic vessel without contravening the synodical decrees, which sought to discourage frequent expositions and processions as they tended to superstition. The council of Cologne (1452), presided over by the papal legate, Cardinal Nicholas of Cusa, forbade either the one or the other, except in the octave of Corpus Christi and on one other day of the year, which must be for a serious reason and with the permission of the bishop... The compromise of the sacrament house was effected by a door of metal lattice work, with a light to make the Eucharist more visible, and sometimes with candles burning on prickets affixed to the outside railings. 

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Stone, marble, metal or wood were used in their construction, but those in wood have disappeared.

Here are some photographs which show some different forms of the sacrament tower. Most shown here are gothic in their design, but some have added elements from later centuries, and one is a rare example in a more neo-classical style. 

Munster in Heilsbronn, 1515

Eglise Saint-Jacuqes de Louvain, 1539. (Note the prickets for candles around the metal base)

Sint-Peterskerk, Louvain, Belgium. 1450.

Sint-Martinuskerk, Aalst (Source)

St. Lorenz, Nuremberg

Saint-Leonard de Leau

St, Martin's, Kortrijk, Belgium

By way of an interesting side note, the Congregation of Rites, in 1863, prohibited the bishop of Limburg from re-introducing sacrament houses within his diocese (while allowing their use where it was already the established custom.) No doubt this decision was taken in view of post-Tridentine preference for the sacrament to either be reserved upon the high altar or in its own chapel -- an idea that was once again affirmed as recently as 1956 by Pope Pius XII and in 1957 by the Congregation of Rites (with some exceptions permitted for immemorial custom).