By The Metric Maven
It is amazing what specific skills a person can develop in a niche profession. My grandfather on my father’s side was an upholsterer. Each Summer I would spend a couple of weeks with my Grandparents in their upholstery shop. I would watch as sofas would be brought into the shop, and as my grandfather removed the worn fabric and cushions a rain of coins and small curiosities would generally hit the floor. After he had repaired and hot glued the sofa frame and such, the fabric was to go back on. It was at this point, that I received my first of many warnings as a very small boy, which I’ve never forgotten. My grandfather would take a handful of tacks (small sharp nails) and put them into his mouth. “Don’t even think about doing what your grandfather just did,” my grandmother would admonish. Believe me, I was never tempted, I was only stunned in slight disbelief. My grandfather would then stretch the fabric with a stretching tool of his own design, and in quick succession bring a tack hammer with a magnetic end up to his mouth, which had a nail head first ready to be plucked, and quickly hammer in a succession of tacks to hold the fabric. It was a mesmerizing thing to watch. For me it was similar to sword swallowing, or fire eating, at a carnival side show. As I recall the tacks had been blued, and on the side of the box it said: Sterile. Apparently my grandfather was not the only one who engaged in this method of applying tacks.
During the summer in the small town where I first lived, I would hear the pounding of nails as houses were being constructed. The frames looked like strange, deformed, beige, whale skeletons with men pounding nails into them. The men generally had a type of half-apron on which had the name of the local lumber company printed on it. The apron had three open pockets where they kept nails, and withdrew them while building a house. One particular day I was tagging along with a fellow named Gunnar, and we went to get nails. Into the hardware store we went, and Gunnar requested ten penny nails. I was certain they cost ten pennies per nail. They must be very good nails at that high of a price. It slowly dawned on me that the designation was not cost, but was some manner of stating their size. Perhaps they weighted ten pennies? Indeed the nails were weighed in a saddle shaped piece of metal which fit into a scale (i.e. a scale-pan). But the weight was in pounds. I began asking how the sizing worked, but do not recall what I was told, other than I found the answer very unsatisfactory. I still had very little idea what this all meant until I decided to write this blog.
According to Wikipedia:
United States penny sizes
In the United States, the length of a nail is designated by its penny size, written with a number and the abbreviation d for penny; for example, 10d for a ten-penny nail. A larger number indicates a longer nail, shown in the table below. Nails under 1¼ inch, often called brads, are sold mostly in small packages with only a length designation or with length and wire gauge designations; for example, 1″ 18 ga or 3/4″ 16 ga.
Penny sizes originally referred to the price for a hundred nails in England in the 15th century: the larger the nail, the higher the cost per hundred. The system remained in use in England into the 20th century, but is obsolete there today. The d is an abbreviation for denarius, a Roman coin similar to a penny; this was the abbreviation for a penny in the UK before decimalisation.
Here is the table:
So the length designations are related to nail prices from the 15th century?—in England—when apparently they used d as an abbreviation for penny?—but actually a Roman coin which was like a penny? How could we in the US ever conceive of changing such an irrational and antiquated system like this? Clearly it suits us.
Of course the British being the stuffed shirts we in the US know them to be have never bothered to change—-oh wait—-here’s what Wikipedia says:
Most countries, except the United States, use a metric system for describing nail sizes. A 50 x 3.0 indicates a nail 50 mm long (not including the head) and 3 mm in diameter. Lengths are rounded to the nearest millimetre.
For example, finishing nail* sizes typically available from German suppliers are:
Hmmm, Wikipedia doesn’t specifically mention the UK, but by omission it leads one to believe that the British probably have had the good sense to measure nails in mm rather than 15th century pricing. If nails had been designated in the metric system when Gunnar was allowing me to tag along with him, he might have purchased an 80 x 3.1 nail and told me it was 80 mm long, and perhaps even 3.1 mm in diameter. The world would have been much more cogent and meaningful. But even today we in the US refuse to change anything involving our weights and measures—no matter how irrational. The slow accumulation of negative consequences of our refusal reminds me of a famous rhyme:
As a metaphor for the lack of metric in the US, I think that nails it. The nail that sticks up, gets hammered down.
If you liked this essay and wish to support the work of The Metric Maven, please visit his Patreon Page and contribute. Also purchase his books about the metric system:
The first book is titled: Our Crumbling Invisible Infrastructure. It is a succinct set of essays that explain why the absence of the metric system in the US is detrimental to our personal heath and our economy. These essays are separately available for free on my website, but the book has them all in one place in print. The book may be purchased from Amazon here.
The second book is titled The Dimensions of the Cosmos. It takes the metric prefixes from yotta to Yocto and uses each metric prefix to describe a metric world. The book has a considerable number of color images to compliment the prose. It has been receiving good reviews. I think would be a great reference for US science teachers. It has a considerable number of scientific factoids and anecdotes that I believe would be of considerable educational use. It is available from Amazon here.
The third book is called Death By A Thousand Cuts, A Secret History of the Metric System in The United States. This monograph explains how we have been unable to legally deal with weights and measures in the United States from George Washington, to our current day. This book is also available on Amazon here.