Quarter leather (originally half?) over marbled paper covered boards. Marbled end papers, all edges blue tinted. Two volumes, complete, volume 1 493 pages plus table of contents, volume 2 478 pages plus table of contents and an index. Illustrated with drawings and diagrams within run of the text. Condition: Some rubbing to the edges of the boards, especially to the corners, where there is some of the marbled paper. Some foxing to prelims and to contents tables, but only occasional foxing to the main content book. The index in the second volume shows some damage: there is a small tear to one of the pages, some insect damage to that same page and the following one, and a small tear to the edge of that second page. There are also ink splashes to the index. Bindings sound.