In 1921, when Rudolf Hommel joined Henry Chapman Mercer on his expedition into China, they found a land untouched by the arrival of machine technology. Grain was planted in holes dug with a long-handled conical stone; it was threshed by slashing the stalks against slatted wooden frames. River-mud bricks were pulled across the fields on sleds with rope handles, then used to build houses which had bamboo roofs and soil floors pounded smooth. The hand-woven cloth was dyed, wrung by hand, and draped on large bamboo scaffolds to dry.

Hommel limited his examination—wisely, in view of the wealth of examples that he found—to primary tools, those which met people's basic needs; he discussed the handicrafting of tools and methods of providing food, clothing, shelter, and transportation. The photographs and sketches are thoroughly documented, and the various processes are explained and, when necessary, located by region.

A review by Florence Ayscough in Books (September 12, 1937) referred to the original 1937 edition of China at Work as a "book which reveals the lives of millions who, in order to remain among the living, must daily hsiang fa tzu—evolve methods—with tools incredibly primitive, yet incredibly effective." Nearly unavailable since that limited first edition, the volume is now more than a historical study; it is a first-hand source book for a time that is now gone.