Historians and researchers have finally solved a long-standing mystery behind one of Victorian England’s iconic architectural wonders. The answer? Simple, standardized nuts and bolts. That may not sound exciting today, but in 1851 the invention allowed engineers to build the Crystal Palace at previously unimaginable speeds.
While the Great Exhibition of 1851 showcased Britain’s most advanced and acclaimed industrial capabilities through a number of displays, the crown jewel of the five-month event undoubtedly came from architect Joseph Paxton. At over 550 meters long, the Crystal Palace was the largest building in the world at the time, with a huge glass roof supported by 3,300 cast iron columns. However, for nearly 175 years, a mystery has puzzled historians: How was it possible for Paxton’s workers to complete construction in just 190 days?
A study published in The International Journal for the History of Engineering & Technology has now solved the mystery. According to John Gardner, professor of English literature at Anglia Ruskin University (ARU), the Crystal Palace relied on a revolutionary thread designed by a man named Joseph Whitmore.
Before Whitworth’s standardized concept, each screw and bolt was unique to each other with no standardized dimensions. This meant that lost screws or broken bolts could easily bring construction projects to a halt, at least until someone made new replacements. Given its immense size and complexity, the Crystal Palace alone required 30,000 nuts and bolts, and yet the use of so many parts somehow did not hinder the building’s construction.
“The thread shapes used in Crystal Palace buildings are not recorded in any of the surviving drawings,” Gardner and his co-author Ken Kiss wrote in their article. “Furthermore, none of the rare existing bolt threads have been measured, recorded and published until 1726544522.”
The reason behind the rarity of the original bolts is that after its deconstruction in Hyde Park and subsequent reconstruction in South London in 1854, the Crystal Palace burned down in 1936. But Kiss, curator of the Crystal Palace Museum, has unearthed one of the last known buildings. bolts from a column at the building’s original location, as well as a nearby water tower built at the time to power the palace fountains. Kiss then provided these archaeological artifacts to Gardner for analysis.
Gardner discovered that the Crystal Palace cap bolt matched Whitworth’s dimensions exactly, years before it became known as the British Standard Whitworth (BSW), the world’s first national specification of its kind. After soaking the water tower nut and bolt in oil and then using a combination of heat, force and hammering, he also discovered measurable threads that also met BSW specifications. To further prove his theory, Gardner fabricated completely new bolts with BSW threads, which matched the original nut perfectly.
According to the study’s co-authors, by adopting Whitworth’s new, standardized option, builders were able to complete the monumental undertaking in a relatively short time. The results were ultimately seen by approximately six million visitors to the Great Exhibition between May and October 1851. But as to why such a detail was overlooked for decades, Gardner pointed to the pace of revolutionary technological change at the time.
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“During the Victorian era there was an incredible innovation of workshops across Britain that helped change the world,” Gardner said in an accompanying statement. “In fact, progress was so rapid that some breakthroughs may never have been properly realized at the time, as was the case here with the Crystal Palace.”
As with the Crystal Palace itself, the exact BSW specification is not often used today, but its legacy has influenced a number of modern variants that do not stray too far from the original dimensions. Likewise, the Crystal Palace, now long gone, inspired modern architecture for decades.
