2. The nail, a simple little device that holds the whole edifice together
Who first thought of it? Most references will tell you that the nail evolved in three phases: a hand-wrought object of pre-history, a ‘cut nail’ which was the first system of manufacturing nail, which dates it to the early Industrial Revolution, and the ‘wire nail’ which is what we think of as a nail today. As with so many construction technologies, the nail first surfaces in history in ancient Egypt, where it facilitated the extraordinary architecture of that society. The Roman Empire, however, was also held together by nails, and quite a considerable tonnage of Roman nails have been unearthed, and in fact, Roman nails are today the most widely accessible and affordable authentic Roman artefact.
Besides that, nails, standardized and portable, have at times in history been a medium of exchange, and in the Christian world, the symbolism of a Roman nail is integral to that of the Cross. The name Naylor, or Nailer, comes from the ancient craft of nail making. In early American house construction, at a time when England was the leading manufacturer, nails were so valuable that a house was typically burned down when abandoned so that the nails could be collected and reused.
Nails are still ubiquitous today, and all in all, we owe a lot to the nail, so it ranks high on the list of humankind’s engineering achievements.