In overall good condition. Boards are all firmly attached, with superficial rubbing and rounding of corners. Spines are in good condition, with minimal wear heads and heels of some. Hinges remain tight with minimal wear throughout volumes. Text blocks exhibit foxing and toning that is not obtrusive to readability. Pullout diagrams and illustrations throughout volumes. Minor wear and toning and diagrams. Minimal marginalia at fronts of some volumes. Infrequent folds to the corners of some pages. Please see photos.

A unique collection of German volumes and pull-out illustrations which highlight some of the scientific and technological processes at the time.