In a footnote to their monumental three-volume technical analysis of the painted panels of the 16th-century Netherlandish painter Pieter Bruegel the Elder, Christina Currie and Dominique Allart acknowledge an unlikely source of help: “We thank Serge Lodrini, Chief Superintendent, Liège Police, for examining these prints for us.”

The prints in question are fingerprints, which Pieter Bruegel has left in several of his works—one by a hole in the ice, for instance, in Winter Landscape with a Bird Trap; another near the dozing cat in Dormition of the Virgin. Bruegel, it seems, occasionally used the side of his thumb or finger to break up the still-tacky glaze, or lighten the paint. Unfortunately, the chief superintendent (or, more likely, his uncredited laboratory) was unable to find sufficient “characteristic identification points” to tie the paintings together—pin the deed on the man, so to speak.