The Smoot – How an MIT prank became a lasting unit of measurement On a chilly October evening in 1958, a group of MIT students shuffled onto the Harvard Bridge, which separates the university town of Cambridge from Boston proper. The shortest among them lay down on the sidewalk at the bridge's start, his friends marked his length, he got up, moved forward, and repeated the process. …
good demonstration of how measurements are largely arbitrary. what matters is the consistency of use. they don't say how many ears there are in a smoot which is a problem for the smoot unit of measurement, otherwise perfectly ok to measure light years in smoots or speed of light in smoots/second.
One might deduce that an early database admin would indeed Send to Queue overnight tasks. Im this case, Queue is very much a British English verb, as in "queue it up."
An American DJ does not stack tracks anymore, but they are still queued for playback and overlay.
And so on. Please wait a bit before going all Grammar Police on a fellow writer. Saves time all round.
Oliver Smoot is (distantly) related to Nobel laureate George Smoot
Also, rather topically alas, to the co-sponsor of the infamous Smoot-Hawley Tariff Act of 1930. (Oliver bears no responsibility for those, of course.)
Having an interest in vintage vehicles, I seem to have developed rather more knowledge of thread systems than I really wanted to. So my early 1950s British motorcycle uses all of the following:
Whitworth (British Standard Whitworth - BSW) - Developed by Sir Joseph Whitworth and modestly named after himself. The hexagonal heads and nuts were quite chunky and in the early 20th Century nuts and bolts were being made with the next size smaller head.
British Standard Fine (BSF) - Developed in early 20th Century with a finer pitch than Whitworth and using the one size smaller head, but otherwise the same.
British Association (BA) - A metric system that starts at 6mm OD and 1mm pitch and then goes down in a geometric progression (as the BA number increases). Whilst the smallest used is typically around 16BA, you can calculate the dimensions of 20BA or even 100BA. When adopted by the British all the dimensions were specified in inches!
Cycle Thread - Mostly 26TPI regardless of size.
British Standard Pipe (BSP) - I suspect we've managed to inflict this on the rest of the world and almost the opposite of BA it's now specified in millimetres.
Although the British have now moved to the metric system there are still gotchas, such as the Japanese using a slightly different (finer) thread for some sizes!
As you can probably tell, I'm an absolute blast at parties (if I were ever to be invited to one)!
And for a time, upto the 1950ies(?), on the continent, you could have metric bolt- and nut-heads on machinery, but 'british' threads. I guess as still functioning manufacturing tools like lathes used the old standards.
Only if you have the proper screw cutting attachment.
My (very well used, now restored) British made Boxford came complete with Imperial screw-cutter (fitted) and a "spare" in metric. Neither match the threads the machine is built with.
The screw cutting attachment is generally considered to be the assembly that advances the tool post at the right speed for the desired pitch. Generally the same one is used for both Imperial and metric, albeit you need to change a pair of gears over to get the options back to round numbers in the "other" system - e.g. a pair of identical gears may be replaced by a pair with 100:127 tooth count.
The actual cutter needs to to be swapped according to the thread profile too, i.e. 60° for ISO metric threads, 55° for Whitworth.
I once saw a machinist making a very large crown nut on a lathe. The thing looked just like the ones you can buy at a hardware store, but was many inches across -- I want to say almost a foot. It was to hold a large piece of industrial machinery down to one of its mounting bolts.
And you don't need to go that old either.
Late 80s Land Rover - similar mix of threads. By then "mostly" metric, apart from the BSF (prop flange bolts), BSW (some of the suspension bolts), and even a mix holding one component in place.
And for fun, the venerable Rover V8 engine (based on an even more ancient Buick engine) kept the same block dimensions and threads (BSW) from it's very first version of 3.5l right the way through to the very last 5l versions. The length of the crank nose changed when they redesigned the front cover, otherwise parts were interchangeable.
Also... Whitworth uses the bolt size as a measurement, not the head.... i.e. if you have a 5/8" Whitworth then the bolt has a 5/8" diameter. If you have 5/8" SAE, then the head is 5/8" across the flats.
Plus, Firefox does not believe "Whitworth" is a word.
I have never heard of SAE threads, but for both UNC and UNF (or ANC and ANF) the number is, like Whitworth and BSF, the diameter of the bolt. In other words, 5/16 UNC, 5/16 UNF, 5/16 BSW and 5/16 BSF bolts are all 5/16" in diameter.
You may be thinking of head sizes, which for metric and UNC/F are given as AF (across flats) but which for BSW/F are given as the thread sizes. So, for example, 5/16 UNF usually has a 1/2" AF head, M7 usually has an 11mm AF head and 5/16 BSW has a 5/16 BSW head which is actually 17/32" AF while 5/16 BSF has a 5/16 BSF head which is actually 1/2" AF. BSF heads are one size smaller than BSW of the same diameter, which is why spanners have things like "1/2" BSW 9/16 BSF" on them.
Impressive trivia knowledge. Having been cursed with ownership of a BMW RG1000GS I was astonished/gobsmacked at the number of different bolt or screw heads on the thing. My 1970s BMW was vanilla metric and Allen keys. Possible to assemble tool kit for going bush. Mostly provided with new bike. The 2010s equivalent required a truck of tools for the same. Why ? Anyone got a list of the types of screw and bolt heads lately ?
If you want to have some real "fun", try adapting the water input fitting on a Rocket espresso maker to US plastic tubing.
It involved the purchase of a BSP to US copper tubing fitting on Ebay, because nobody sells (affordable single unit quantities) of BSP to US fittings. The fun was figuring out what was on the Rocket, because it came with absolutely no documentation (used). The challenge was even more fun, because I was in Hawaii at the time. Problem was solved, because not having coffee is a powerful motivator.
I'd pick up the phone and call McMaster-Carr for the proper adapter, or possibly Grainger. You can try mcmaster.com and/or grainger.com ... and then break out the Mellita and have a cuppa coffee while you wait for the part to arrive.
Or head for your local machine shop and have them make one for you. I'd do it for free for a friend/neighbor. It's hardly rocket surgery.
After all that, for day-to-day use I'd probably stick with the Melitta. They are cheap, make great coffee (assuming you start with great coffee, GIGO really applies here), are easy to clean, take no room to speak of, work in a power failure[0] (if you haven't bought into the "electric cooking will save the planet!!!" myth), etc. What's not to like?
[0] Or over a campfire.
You have indeed inflicted BSP on the world as the G series of fittings is BSP equivalent in size and pitch but is usually still specified in inches in North America at least.
i.e. to fit a G1/4 fitting you can tap the hole 1/4BSP.
I like the bit where they adjusted the size of the paving slabs. That's not an inconsiderable effort, and must have come at some expense to the Commonwealth. Perhaps that's better not mentioned?
Could it be possible that the civil engineer assigned to the project had some connection to MIT and/or the fraternity involved?
I'm guessing for the contract it might have been worth the contractor offering to make a few moulds for the odd size, or it might even have just required changing the cut point on an automated line.
I'm not sure if the slabs will be individually molded, or made on a convayer with a slice at the required timing for the size.
either way if, as seems the way the authority in charge of the work respects the history of the measurement it seems like something that any canny supplier might consider worth trying to show they were willing to go the extra mile (or 945.7 smoots).
As a celebration of the individual, and as a nod to his comments about privacy/data sharing, could I suggest in addition to using the Smoot as a measure of distance, we use it as a measure of time, as used in the sentence - "it took us x Smoots to be in the position we are now with regards privacy & data sharing". Obviously I would bow to the individual to define a time based metric for "the Smoot"
The 'Helen' is a measure of a woman's beauty.
Helen of Troy was reported to be so beautiful that her face "...launch'd a thousand ships...".
Hence, a millihelen is the amount of beauty which will launch one ship (actually, there were 1186 ships in the Battle of Troy, so Helen's beauty is, most precisely, 1.186 helens.
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