Hardcover, New. First edition, SIGNED BY AUTHOR, colour illustrations, appendices, index. From their mid-nineteenth-century fencing business the Harpers of Aberdeen developed a unique system of suspension that allowed their light foot suspension bridges to be relatively rigid. John Harper was one of the first to employ steel wire rope, now universally used. The Harpers' innovative work overcame the disadvantages of this type of bridge and was of considerable benefit to those who relied upon them. Harpers built over sixty such bridges throughout the UK and the British Empire between 1870 and 1... View More...
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