This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
To burnish an article is to polish it, by removing the small roughness upon its surface; and this is performed by a burnisher. This mode of polishing is the most expeditious, and gives the greatest lustre to a polished body. It removes the marks left by the emery, putty of tin, or other polishing materials; and gives to the burnished articles a black lustre, resembling that of looking-glass. The form and construction of the burnisher is extremely variable, according to the respective trades; and it must be adapted to the various kinds of work in the same art. In general, as this tool is only intended to efface inequalities, whatever substance the burnisher is made of is of little consequence to the article burnished, provided only that it is of a harder substance than that article.