As indicated in A Source Book for Rule Collectors, p. 231, this is a folding or take-down tailors' square which is not uncommon in the nineteenth century. It was used in both the measurment process and in drafting the pattern. This boxwood square is dated to the late nineteenth century as it consistent to the description and pictures shown in the book, however the actual working period of the maker, E. Driver, is yet to be found.
