The D7 Tractor: A Visual History of the D7 Tractor in US Army Service 1941– 1953 is part of Ampersand Publishing Company’s Visual History Series of single-subject reference books. Books in this series feature historical introductions followed by extensive period and walk-around photographs in black-and-white and color. The D7 Tractor, by renowned military author David Doyle, features two pages of introductory text, while the balance of its 120-page length is filled with photographs.

The two-page introduction provides background on the development of the Caterpillar D7 tractor. Caterpillar was formed in 1925 by the merger of the Best Gas Tractor Company and the Holt Manufacturing Company. Holt supplied tractors to the US Army during World War I using Caterpillar as its trade name. The D7 was the primary tractor used by the Army during World War II, and early in the war it was used as a prime mover for artillery and earthmoving equipment. It was only later in World War II that bulldozer blades were added to the D7 tractor.

The introduction includes a description of the various models of the D7 which were developed. These were designated by prefixes and serial number. The World War II D7 engine was a four-cylinder 80 HP diesel engine of Caterpillar design. The tractor used a small two-cylinder gasoline engine as a starter for the diesel engine. Development of the engines for the D7 continued through the 1980s. The introduction describes the various bulldozer blades that were added to the D7 tractor including straight dozer blades, angle dozer blades, and tilt dozer blades.

The remaining pages of the book feature photographs with captions describing the equipment, how the tractors were used, and the setting of the photo. Most of the photos are black-and-white, with the last section of the book featuring a walk-around series of color photos.

The photos start with some illustrative views of the D7 tractor at proving grounds, illustrations of the various dozer blade types, photos of the tractors being assembled or repaired, and photos of students and mechanics repairing the tractors. Other types of equipment such as towed road graders, scrapers, and cranes used and powered by the tractors are included in the photos. The book also includes photographs of various armored cab protections for the operators. The photos include the D7 tractor as it was used in all theaters of World War II and during the Korean War.

In fact, the bulk of the book shows the tractor being used in various operational situations during World War II and the Korean War. Each of the photographs illustrates the many uses of the tractor, and they are a great inspiration for dioramas. The captions for the photos describe the situation and the equipment types on the tractor (particularly which dozer blades and power units are being used). The photographs are clear and large enough to be used as detail references by modelers.

The last 22 pages of the book are color photographs of a fully restored caterpillar D7 heavy tractor that is equipped with a LeTourneau XD7 bulldozer blade and uses a rear mounted LeTourneau R7 power control unit. The walk-around photos show detail of many parts of the restored D7 and will be a handy reference for model builders.

In summary the book is an excellent visual history of the D7 tractor with many detailed photographs and many great ideas for diorama settings. The book is highly recommended for those interested in World War II, in particular construction equipment, and is a must-have reference for those building a Caterpillar D7 kit.

My thanks to Ampersand Publishing for providing this book for review, and my thanks to IPMS/USA for allowing me to review it.