Sentence:  The hay-trusser deposited his basket by the font, went up the nave till he reached the altar-rails, and opening the gate entered the <WSD>sacrarium</WSD>, where he seemed to feel a sense of the strangeness for a moment; then he knelt upon the footpace. 
Meaning of the word marked with <WSD> tags:  The area surrounding the altar of a Christian church; the sanctuary or piscina. Sometimes specifically a drain directly to the earth, perhaps including reference to a basin, for washing vessels from consecration.