The design of these lecterns can vary but in the context of which we speak, they are frequently quite large in size, meant to hold large liturgical books such as the Graduale and Antiphonale as well as other liturgical books.
Such standing lecterns were frequently found within the chancel or wherever the Divine Office was celebrated -- in Italy, for example, it is common to find them behind the high altar as in the image above which comes from San Simpliciano in Milan.
Frequently these lecterns included symbols, particularly symbols of one of the Four Evangelists, such as the Eagle (St. John) or Lion (St. Mark) for example. In medieval England, eagle lecterns -- where an eagle with its outstretched wings became the support for the book -- were quite widespread in the thirteenth and fourteenth centuries.
In terms of the materials, this sort of lectern was frequently made of wood, bronze or brass. Here are just a few more examples of this impressive piece of liturgical furniture.
