# The metric system: Make your case for it and why we should switch to it. (As if we haven't already)

And in survey, we use decimal feet (when we aren’t using arcane bullshit like rods and chains, anyway…).

I just timed it. It took me eight seconds to determine that 30oz. is 887.206ml. And even if you were illiterate and uneducated, I’m sure the waitress would gladly bring you a 30oz. cup to display to you how much liquid it held.

So because it may take a welcome visitor eight additional seconds, or a quick question, to determine his beverage size, we should retool the whole thing and rethink our system of measurement?

I’ll grant you the driving distance and speed one. But all the others are just labels. You might buy your cup of coffee in ounces, but plenty of folks buy coffee just as well using the labels “tall” and “grande”. “Give me a 12 ounce coffee” is exactly equivalent to “Give me a tall coffee”: Both are mere labels. You don’t need to know the numerical ratio of the volumes of “tall” to “grande” to know which coffee size you prefer. Likewise you could call your paper “American standard letter”, and it would serve the exact same purpose as calling it “8.5x11”. And I don’t know if anyone’s ever actually made one, but one certainly could make a thermometer with no numbers, just labels saying “Short sleeves” and “down coat”, and the like.

What is the difference?

Ah a later post explained the difference:

Q. How does such a small discrepancy between unit definitions cause serious problems in surveying and engineering?
A. Although the U.S. survey foot is longer than the international foot by only 2 parts per million (ppm), this small discrepancy accumulates over large distances and can result in significant errors in surveying and civil engineering projects, regardless of the size of the project. For example, when a one-mile distance is surveyed, the difference is approximately 0.01 ft (or 0.12 in).

That difference is trivial to the normal user and they are getting rid of it.

‌‌‌‌‌

The problem with “getting rid of it” is that all of those old records still exist… better be careful (and convert to metres, plus specify a geodetic datum, etc.) when entering data into your computer application.

Wait a minute.

A. Although the U.S. survey foot is longer than the international foot by only 2 parts per million (ppm), this small discrepancy accumulates over large distances and can result in significant errors in surveying and civil engineering projects, regardless of the size of the project. For example, when a one-mile distance is surveyed, the difference is approximately 0.01 ft (or 0.12 in).

Let us take the tallest building in Los Angeles 1,100 feet. 1/5th of a mile.

Thus the difference would be 1/5th of 0.01 ft aka .002 ft. Or, 0.024 inch. A fifth of a inch. Not a whole foot. No wonder he declines to name it.

I was just using it as an example, but you guys should retool the whole thing and rethink your system of measurement because literally - and I mean that in its proper sense - the entire rest of the planet is using the Metric system, and it’s not because of some elaborate conspiracy to impurify your nation’s bodily essences by forcing you to switching to a measurement system that makes sense.

I appreciate the US is such a large and diverse country there’s often not much reason to leave it, except maybe for a quick trip to Canada or Mexico, but when you’re travelling internationally it’s amazing how much difference it makes when everyone is on the same page about basic stuff like weights and measures.

Doesn’t matter whether you’re in a cafe in Sydney or a supermarket in Paris or buying a drink from a roadside stall in Indonesia, everyone’s on the same page about fundamental stuff like “what size drink you’re getting” and “how far it is to the next point of interest” and a whole bunch of other stuff that doesn’t really come across well in a text discussion but absolutely makes sense when you’re there experiencing it.

You’re assuming that the discrepancy was in the measurement of the height of the tower. That’s unjustified. It might have been, for instance, in the distance between the tower and the flight path (with buildings more directly in the path needing to be under a certain height). That could be a matter of miles, but worse, the origin of the coordinate system they used might be even farther away.

Also, the magnitude of the error doesn’t necessarily matter here. If the building is a fraction of an inch over the limit, then it has to be redesigned. In fact they might have intentionally designed the building to be right at the absolute edge of the limit, and then finding that they’re slightly over, had to remove a full floor.

But I guess you know more than some guy working at the National Geodetic Survey.

He said a foot.

and it was almost certainly this - The main changes to the updated advisory circular are as follows:

** Federal law requires that the FAA determine whether a structure that is proposed to be built or altered, 200 feet above ground level (AGL) or higher, or near an airport, does not pose a hazard to the airspace. To remain consistent with changes to the Code of Federal Regulation (CFR) Part 77, the height of a structure identified as an obstruction has been lowered from 500 feet (AGL) to 499 feet (AGL). All structures above 499 feet are considered obstructions and the FAA will continue to conduct an aeronautical study on these types of structures to determine their effect on the navigable airspace and ensure they do not create a hazard.*

So yeah, a 500 ft building would be “an obstruction” and other rules apply. Such as lights.

I do not
“know better than he does” by any means. But his example is mathematically wrong.

He said a floor, not a foot. And if your building is 500.01 feet tall, but needs to be 499.99 feet, then the fastest way to redesign it might well be to lose a floor.

But regardless, you’re still assuming that the foot/foot discrepancy is in the height. As opposed to something else, like “the tower is 150,000 feet from this reference point, while the end of the runway is 125,000 feet, which puts the tower so many feet away from the flight path, etc.” And therefore getting the difference entirely wrong due to the mixup.

I don’t know what a random FAA page has to do with this story.

That is worse. You can shave .024 of a inch off a whole floor.

But that is not what he said.

I think he just made the example up. But you can think otherwise. The difference in any case is tiny.

In normal everyday usages, it makes no difference at all. And, they are getting rid of it.

I mean, if this is your best example of why the English system is bad- you lose.

You misread the quote, made a ton of unjustified assumptions, and now claim that redesigning every floor of a building is easier than dropping a single floor. Oh, and are calling a guy that does this for a living a liar. Good luck with that approach.

Again: I’ve dealt with these issues in real life. Have you?

You are both right, I give up.

As a general rule, I would say there are three broad areas where small discrepancies can make a difference.

The first is when you simply need high accuracy. A couple parts per million is somewhat unusual, but by no means unheard of. Gauge blocks achieve parts per million accuracy and they’ve been around for over a century.

The second is when the object is very large. This isn’t too surprising; errors get magnified the larger you get, so eventually you exceed even modest accuracy requirements.

The third and perhaps least obvious one is when there is a large distance to the origin of the coordinate system. Perhaps you have a small object with only modest accuracy requirements, but all the dimensions are measured relative to something miles away. Then, your measuring apparatus needs extremely high precision (which gives you high accuracy when the difference is taken). Using the wrong unit affects both precision and accuracy and so can cause serious problems here.

Surveying is a case where this third problem often comes into play, since it’s all about making measurements relative to some other distant reference point.

Also, people don’t buy gasoline by the gallon, either - they either fill up their tank and pay whatever it costs, or they set a sum of money in advance. The actual units could be gallons, liters or hogsheads and for the vast majority of people, it wouldn’t make a difference.

This is the problem, that most people don’t have to actually do complicated calculations, and the measurements most people do are fairly straightforward.

Probably the most difficult calculation most people do is something like figuring out how much paint to buy for the living room, with X number of gallons of paint for Y number of square feet. Because most people suck at even basic math skills, even doing it in units they are familiar with, they don’t like it.

Having moved from America to overseas, it’s not that difficult to learn but I think most people just don’t want to try.

I just wish they would admit that, instead of all the handwavey “But the way I’ve always done it is better!”

And I’d like a pony.

If United Statians can convince the rest of the world to standardize to American units then we can avoid going metric because the whole world will finally all be on the same page (even though it’s inferior to metric, it’d at least be standard).

But since that is not going to happen maybe we could go metric? You know, for kids?

Side Note: I have a theory that if vaccines in the US were measured in cubic inches or ounces instead of cc’s 90% of Merkins would be vaccinated.

Like universal healthcare and fixing bridges.

Why do you hate freedom?