 Complete the following phrase:  After the First World War, as donors and philanthropists as well as Belgiums famed instrument makers started becoming scarcer, only about a thousand instruments were added to the collections between 1924 and 1968. Until 1957, the curators at the head of the MIM; Ernest Closson 19241936, his son Herman 19361945, and René Lyr 19451957 limited themselves to preserving the already collected instruments, in not always satisfactory conditions. Ernest is notable for editing several articles on Belgian makers for the National Biography and devoting a long monograph to La facture des instruments de musique en Belgique, which appeared at the 