Asperging words

Here’s a verb I don’t remember encountering before. It crops up near the end of this passage in Seamus Deane’s novel Reading in the Dark (1996), where the author describes a dramatic childhood winter in Northern Ireland:

The Germans came only once, made a bombing run on the docks where the American ships were lined up in threes and fours, missed, and never came again. The sirens had given several false alarms before, but this time the throb of the approaching planes seemed to make them more frenetic. We woke to their wild moanings, were carried to safety under the stairs and cradled sleepily between our parents, lightly asperged by the bright drops of cold Lourdes water that my mother would every so often sprinkle on us. I remember the silence when the droning stopped and then the long lamentation of each plane’s dive.