When prehistoric man picked up his first stone he would not appriate that its weight was due to the effect of gravity on its mass. Soon, though, he would learn that large objects were sometimes lighter thansmaller ones and that he would need an aid to help compare weights and values. Today we accept weighing as part of everyday life, using its principles as measures of our ideas of justice, but giving methods of weighing little thought. Weighing, however, is an ancient art, which has excercised the minds of philosophers, scientists, engineers and even the dishonest for at least six thousand years. This book shows how men strove to produce a machine which could compare more accurately, or more quickly, or would meet a special need or perhaps even sell more cheaply. With the aid of many illustrations and non-technical language some essential knowledge of the principles of weighing is provided.About the authorThe late JT Graham had a considerable collection of old weights and measures and was a senior officer in the weights and measures department of a large local authority. For eight years he was the editor of "The Monthly Review", the journal of the Institute of Trading Standards Administration (ITSA); he was also the author of two books. The late Maurice Stevenson, who revised this book for its third edition, was a senior inspector of weights and measures and an enthusiastic collector of old weights and measures.. From 1962 to 1974 he ran a Weights and Measures History Circle and edited its bulletin "Libra". In 1979 he carried out research at museums on old verification stamps under a grant from the British Academy.Graham, J. T. is the author of 'Scales and Balances' with ISBN 9780852635476 and ISBN 0852635478.