Sentence:  What are the <WSD>supernumeraries</WSD>? upon whose report are they employed?— ... [I]f it is temporary employment, or for a temporary situation only, as occasion may require, such as the <WSD>supernumeraries</WSD>' situations, for instance, these are looked upon as temporary appointments, although, from the great increase in our business, they have been in some respects permanent. 
Meaning of the word marked with <WSD> tags:  A person who works in a group, association, or public office without forming part of the regular staff (the numerary). (from early 17th c.)