The Iron Bridge: Symbol of the Industrial Revolution, 2nd ed. (review)

Even before it was completed, the Iron Bridge spanning the River Severn at Coalbrookdale, Shropshire, England, had become a subject for artists. After it opened, on New Year's Day, 1781, the bridge attracted tourists, who might stop at the nearby ironworks to see a blast furnace tapped, watch the painters at the Coalport porcelain works, then climb the hill to view the industrial panorama below. A hotel rose at the span's northern end to accommodate visitors, and the image of the great semicircular iron arch adorned tankards, plates, and billheads. But the Iron Bridge was more than a curiosity: it demonstrated the importance of the iron industry and iron's theretofore untapped potential as a construction material.

The Iron Bridge: Symbol of the Industrial Revolutionfirst appeared in 1979. With this second edition, Neil Cossons and Barrie Trinder offer a substantially updated work. "Such has been the pace of research during the last two decades, that this is in effect a new book," they write (p. xi). It is also a welcome one, for not only have the authors incorporated scholarship that has appeared in the intervening period, they have also corrected a serious oversight of the first volume, the omission of references. The result is a handsome and thoroughly documented history befitting this landmark of international significance.

The authors, who formerly worked together at the Ironbridge Gorge Museum Trust (Cossons as museum director, Trinder as honorary historian), anchor their story within the essential contexts of regional industrial development and engineering practice. In 1709, Abraham Darby (1678- 1717) succeeded in making iron using coke (rather than charcoal) at his ironworks in Coalbrookdale. By the late eighteenth century, the manufacture of iron had been more fully developed here than in any other part of Great Britain. Iron was part of the district's very fabric, used for a multitude of purposes—domestic, agricultural, and industrial. The Iron Bridge, the authors write, was "the logical outcome" (p. 3) of this evolution, a practical means of solving a problem that had become a barrier to commercial and social life: the lack of a bridge across the Severn Gorge.

The traditional masonry arch, or series of arches, would not do in such a heavily trafficked river; a wooden bridge might suffice, but it would inevitably be short-lived. In 1773, Thomas Farnolls Pritchard (1723-77), a Shrewsbury architect, proposed to build an iron bridge. By 1775, promoters had published notice of their intent to petition Parliament ("Iron Bridge over the Severn"), and Abraham Darby III (1750-89), whom the authors call "the creative genius of the project" (p. 19), had agreed to build it. The book traces the somewhat fitful course of the project from inception through completion, duly recognizing the skilled but anonymous mechanics and workmen who contributed talent and brute strength to a bold enterprise.

The subsequent history of the Iron Bridge, the authors concede, is "a narrative of repairs and maintenance" (p. 47). Though the bridge withstood the ravaging flood of 1795, it was bedeviled from the first by the shoddy construction of its abutments. Increasing loads led to the structure's demotion from a vehicular to a pedestrian bridge in 1934. In 1967, the Ironbridge Gorge Museum Trust was created and soon stepped in to initiate a lengthy program of rehabilitation. Today the Iron Bridge again draws tourists, including industrial archaeologists for whom it represents a beloved shrine.

Fully one-half of the book consists of an extended look at the iron bridges and aqueducts that followed the Coalbrookdale arch, both in Europe and the United States. (Eric DeLony, chief of the Historic American Engineering Record of the National Park Service at the time of publication, prepared the U.S. essay, which appears as an appendix. He also contributed the foreword.) With few exceptions, these were modest park and estate bridges, for cast iron offered compressive strength but only modest tensile strength; thus, while it...