The first comprehensive technical guide to automobiles. A rare complete set of the first comprehensive technical work on automobiles. Volume I is the revised second edition and, given the set is uniformly bound and aged, it is likely they were purchased together and that volume II is a first printing. An exceptionally nice set, given that most were used in workshop settings and are correspondingly rare in nice condition.

This set is a remarkably detailed and copiously illustrated technical manual covering all aspects of automobiles, from the laws of thermodynamics as they relate to gases in an engine, to the individual types of drives, shafts, and gears, and the layout of the entire car. Author P.M. Heldt was the editor of The Horseless Age, the first and most influential of the early car magazines, still published today as Automotive Industries. As the author writes in the preface, this text was originally published serially in The Horseless Age and then as a book for 'greater advantage as a work of reference'. He also explains that, 'although the automobile industry has developed in recent years at such a rapid rate that it now ranks among the leading industries of the country, there has not been published a handbook dealing comprehensively with the subject of automobile design. It is true that two or three small volumes on automobile engineering are extant, but they are quite limited in scope and leave unanswered many questions which come up in designing a motorcar. The need for a comprehensive work on the subject has often been strongly impressed upon the author, who has frequently been asked to name or recommend a book of this nature, and not being able to do so, he resolved to make an attempt to supply this deficiency in automobile literature'.

Second edition, revised of vol. I, vol. II likely first edition; 2 vols, 8vo; each volume with integral pouch to rear board containing folding diagrams, 20 and 29 respectively, numerous illustrations within the text of both volumes, occasional small marks but overall contents clean; original brown cloth, titles to spines gilt, boards blocked in blind, cloth rubbed with some wear at the tips a few marks, very good condition.