Hagioscope

A hagioscope (from Gr. άγιος, holy, and σκοπεῖν, to see) or squint, in architecture, is an opening through the wall of a church in an oblique direction, to enable the worshippers in the transepts or other parts of the church, from which the altar was not visible, to see the elevation of the host. They were also sometimes known as "leper windows" wherein a squint was made in an external wall so that lepers and other non-desirables could see the service without coming into contact with the rest of the populace.

In medieval architecture hagioscopes were often a low window in the chancel wall and were frequently protected by either a wooden shutter or iron bars. Hagioscopes are found on one or both sides of the chancel arch; in some cases a series of openings has been cut in the walls in an oblique line to enable a person standing in the porch (as in Bridgwater church, Somerset) to see the altar; in this case and in other instances such openings were sometimes provided for an attendant, who had to ring the Sanctus bell when the Host was elevated.

Though rarely encountered in continental Europe, they are occasionally found to serve such purposes as allowing a monk in one of the vestries to follow the service and to communicate with the bell-ringers. Sometimes squints were placed to enable nuns to observe the services without having to give up their isolation. The unusual design of the church of St Helen's in Bishopsgate, one of the largest surviving ancient churches of London, arose from its once having been two separate places of worship: a 13th-century parish church and the chapel of a Benedictine convent. On the convent side of the church a "squint" allowed the nuns to observe the parish masses; church records show that the squint in this case was not enough to satisfy the nuns, who were eventually admonished to "abstain from kissing secular persons," a habit to which it seems they had become "too prone".

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