General Introduction

The NCBI Historical Book Tag Set (hereafter NCBI Historical Tag Set) is a layer on top of the NCBI Book Tag Set, specifically designed to describe historical materials. The NCBI Book Tag Set defines elements and attributes to model a wide variety of books (such as pamphlets and monographs), describing both the metadata for a book and the content of the book. The Tag Set can also be used to describe only the metadata for a book, if full digitized textual content is not available. The NCBI Historical Tag Set adds, to the structures of the NCBI Book Tag Set, information relevant to the digitization of historical works, for example metadata concerning the digital edition.

The NCBI Historical Tag Set makes several levels of changes to the NCBI Book Tag Set. Some new elements and attributes have been added, the models of existing elements have been broadened to include the new material, new attribute values have been added to existing attributes, and the way in which the <annotation> element is used has been changed. Elements unique to the Historical Book DTD include:

Annotations of historical material are considered to be of two types: 1) those which add words to the text (for example, a penciled marginal note) and 2) those that merely decorate words already in the text (for example, a phrase underlined in pencil). Text-bearing annotations (i.e., those with new content) use the inline <alt-term> element or the <annotation> element. Decorations use the <named-content> element to surround words in the original text, with the attribute content-type taking values like “pencil underline” and “yellow highlight”. The <annotation> and <named-content> elements are not unique to the Historical Book Tag Set; they were already defined in the NCBI Book Tag Set, but they have been put to new uses and may be used in new places. For example, in the NCBI Book Tag Set, the <annotation> element is used only within citations. In contrast, in the NCBI Historical Tag Set, this element is a block-level element at the same level as a paragraph as well as an inline-element inside textual passages. New attributes were added to <annotation> to describe some of these new roles and purposes.

The following structures added in the NCBI Historical Tag Set:

Subsidiary section:

Implementor’s Note