About "Metal crafts in architecture,bronze,brass,cast iron, copper,lead and current developments, was originally planned to be a part of this one ,the decorative metals used in architecture,wrought iron doors gates excepted. to include all the material in one vol-ume made it unwieldy in thickness, and in addition, it seemd advisable to separate the ast metals from wrought iron becausegenerally the latter is so faultily designed in terms of the former.