I have often defined modern structure in buildings as industrialized structure. The obsolete materials and systems we work on – cast-iron columns, wrought-iron beams, weird forms of reinforced concrete from 1910, and so on – are all based on industrial production. (I did once run into an engineer who thought that “wrought-iron beams” meant that they had been made by a blacksmith pounding metal on an anvil, rather than rolling in a mill. I could not disabuse him of that idea.) Pre-modern structure, which is to say, everything in human history until the last two hundred years or so, was made by hand, including with some elaborate tools.
The nails in the photo above were all recovered during the restoration work at the Roslyn Grist Mill. Some may date from the original construction of the mill in the early 1700s, some may be from later alterations and repairs. What is worthy of note is that no two are exactly alike because each was made individually by a blacksmith. Structurally, they’re all the about the same, with the same capacity in shear and tension, more or less, even if their dimensions vary slightly. The plastic folding table that they’re sitting on, on the other hand, is as close to exactly identical to others of its brand as is possible.
I’m not an antiquarian, nor is anyone I know in our field. It’s possible to respect the skill that went into making those nails without regretting the ease with which a machine can now churn out thousands of identical nails in a short time.