how do you read a ruler?

[BrokenPaw]

OK . . . today I'll do my part by sending telegrams to NHTSA and the DOT demanding that speed limits on interstate highways henceforth be expressed in furlongs per fortnight

1.79988e12 furlongs per fortnight.  It's not just a good idea; it's the law.

My favorite quote on the difficulty of getting people to convert from one measuring scheme to another is courtesy Neil Gaiman and Terry Pratchett:

NOTE FOR YOUNG PEOPLE AND AMERICANS: One shilling = Five Pee. It helps to understand the antique finances of the Witchfinder Army if you know the original British monetary system:

Two farthings = One Ha'penny. Two ha'pennies = One Penny. Three pennies = A Thrupenny Bit. Two Thrupences = A Sixpence. Two Sixpences = One Shilling, or Bob. Two Bob = A Florin. One Florin and one Sixpence = Half a Crown. Four Half Crowns = Ten Bob Note. Two Ten Bob Notes = One Pound (or 240 pennies). One Pound and One Shilling = One Guinea.

The British resisted decimalized currency for a long time because they thought it was too complicated.

So it's not just us Yanks who are opposed to change.

-BP

[Brad Johnson]

Brad Johnson wrote:
You use the metric system every day more than you realize.

Explain.

'Centi' is one one-hundreth of something. One cent is one one-hudredth of a dollar.

'Mega' is one million of something. How many megabytes of RAM does your computer have?

'Giga' is one billion. Same computer, but now we're talking hard drive capacity.

What caliber handguns do you have? Chances are you have at least on 9mm in there somewhere.

Ever used a micrometer?

Also, have you ever noticed that scientific measurements, even done with English units, are in tenths and not fractions? Besides, a 1/2" S&W Magnum just doesn't sound right.

Brad

[Perd Hapley]

Using decimals, tenths and hundredths is not the same as using the metric system.  If I say that something is 3.5 inches long, I am not using the metric system.  I am not using the metric system every time I use base-ten numbers.  Cents have nothing to do with the metric system, nor do byte measurements.  I have no 9mm's and likely never will.  I do plan on getting an 8mm Mauser some time.  Do I consider myself currently metric-free?  No.  I'm not fanatic about it.

[Brad Johnson]

Cents have nothing to do with the metric system, nor do byte measurements.

The prefixes are common to the metric system, and so directly apply. The commonality of usage, especially in the electronics industry, is a direct descendant of the development that took place for these products in metric-only countries.

I still am more comforable with SAE measurements because that's what I grew up with, but the fact remains that the metric system is a better all around system of measurment.

Brad

[HankB]

1.79988e12 furlongs per fortnight.  It's not just a good idea; it's the law.

You rounded that a bit, but what the heck, it's all relative . . . and you'd really have to be warped to break that speed limit . . .

[BrokenPaw]

You rounded that a bit, but what the heck, it's all relative . . . and you'd really have to be warped to break that speed limit . . .

Hey, I was just trying to make light of an otherwise serious subject.

I figured you'd just wave that particle-ar rounding error through.

-BP

[Perd Hapley]

Cents have nothing to do with the metric system, nor do byte measurements.

The prefixes are common to the metric system, and so directly apply. The commonality of usage, especially in the electronics industry, is a direct descendant of the development that took place for these products in metric-only countries.

I still am more comforable with SAE measurements because that's what I grew up with, but the fact remains that the metric system is a better all around system of measurment.

Brad

The numbers are also common to the metric system.  That we've borrowed a few prefixes might make it easier to change to metric, but that's got nothing to do with it being a better system, nor does it make my pennies and dollars "metric."  But were the prefixes originally brought into the language for the metric system, or did we already have them?

[Marnoot]

But were the prefixes originally brought into the language for the metric system, or did we already have them?

They're all latin prefixes, and thus predate the metric system by over 2500 years. Don't know about their original importation into English. But I'm pretty sure that linguistic importation also predates the metric system. Words like "cent", etc., far predate the metric system in the english language.

[Art Eatman]

Is somebody trying to tell me that those old Romans, who gave us the whole "centi" and decimal stuff back around 2,000 and more years ago, used meters?  Liters?  Grams?

I don't think so.

A "meter" is defined as the distance between two lines on a platinum-iridium bar, stored in an inert atmosphere somewhere in France, I forget the location.  It's possible that it was re-defined by the wavelength of a certain width in the light spectrum, but it's been a long, long time.  I can't remember ALL this danged stuff, and I'm too sorry to look it up.  That's for you young guys.

A sillymilli-meter is, technically, 0.03937 inches, so everybody rounds it off to forty thousandths and you can change jets in the carburetor and grind crankshafts and bore cylinders without being confused at all.

A 75mm cannon shows about a three-inch hole, which is more than I want to stand in front of, anyhow.  It's a known fact that one round from the 75mm sundown cannon at Cullver Academy did Bad Things to somebody's yacht down at the marina.  It was supposed to have been a blank round, but some evil student had an imagination, which, when coupled with curiosity, resulted in a notable amount of perturbation.  Not me; a guy named Yates.

My car's odometer is in miles.  The speedometer is in miles per hour.  I don't want to unendingly have to do conversions while driving from Terlingua to Tallahassee.  No.  And I ain't gonna change cars anytime soon.  Scroom.

You might have gathered that I don't take all this SAE/metric stuff seriously.

That's astute of you; I don't.

, Art

[Brad Johnson]

A "meter" is defined as the distance between two lines on a platinum-iridium bar, stored in an inert atmosphere somewhere in France, I forget the location.

And an inch was the distance between the tip and first joint of the king's finger. A foot was, well, his foot. Since the dang kings kept dying off and new ones replacing them, sure made for some confusion. "Whaddya mean? It was a foot last week!! Yeah, well the king this week has bigger feet! I want a refund!"



Brad

[Iain]

Art, you've got the better part of half a century on me, but I expect we'll both be dead before the US and the UK cease measuring distance in miles.

I think Brad's point is about the base 10 (that's the correct term, right?) system. Those latin prefixes refer to a system that uses 10's, 1,000's and so on, rather than there being 16oz to a pound, 14 pounds to a stone and 25 stone to a Giant Haystacks. Do believe that the Roman's used a 12 inch foot though (see link below).

Just been reading about troy pounds and avoirdupois pounds.

http://www.unc.edu/~rowlett/units/custom.html - all sorts of bits and pieces like that at the link. edited to add - Recommend reading the bit on volume, I was unaware that there are three different gallons - US dry, US liquid and British Imperial.

[Brad Johnson]

I think Brad's point is about the base 10 (that's the correct term, right?) system. Those latin prefixes refer to a system that uses 10's, 1,000's and so on, rather than there being 16oz to a pound, 14 pounds to a stone and 25 stone to a Giant Haystacks. Do believe that the Roman's used a 12 inch foot though (see link below).

'zactly.

Brad

[Perd Hapley]

Base ten usually refers to the normal numbering system that you and I are familiar with.  It is always used with either Imperial or metric measurements, and is the world standard.  

Wikipedia:

In the decimal (base-10) Hindu-Arabic numeral system, each position starting from the right is a higher power of 10. The first position represents 100 (1), the second position 101 (10), the third position 102 (10 × 10 or 100), the fourth position 103 (10 × 10 × 10 or 1000), and so on.

Fractional values are indicated by a separator, which varies by locale. Usually this separator is a period or full stop, or a comma. Digits to the right of it are multiplied by 10 raised to a negative power or exponent.

Consider 348.5

The 3 has a value of 3 hundreds, the 4 has a value of 4 tens and the 8 has a value of eight ones.  the 5 has a value of 5 tenths.  

The same number in the binary system (base 2) used by computers is:
101011100     So, the left-most number has a value of 1 times 256,
                                                    the next has a value of zero times 128,
                                           the next has a value of 1 times 64,
                                                                             then zero again,
                                                                               then 16,
                                                                                       8,
                                                                                       4
                                                                           and two zeros.

                                                                                      348
Or, that's as close as I can get.

[Perd Hapley]

So, if we extend the base ten system past the decimal point, rather than using fractions like 1/2 (a tenth is still a fraction no matter how we write it, so we must be using the wrong word here) we're then using the metric system?  I don't think so.  

I can talk about 37.76454 inches all day long, and I don't see how I'm any closer to the metric system.  If I say 3 1/4 km's, am I no longer metric?  And when did America start using cents?  Can that be shown to have a French, "metric" influence?  

And what about these metric-Americans lusting after our women?

[HankB]

. . .Just been reading about troy pounds and avoirdupois pounds. . . .

Had some trouble with a teacher back in grammar school about that - she made the mistake of asking "Which is heavier, a pound of feathers or sixteen one ounce gold coins?" and didn't like my answer.

She liked it even less when I PROVED she was wrong . . . in front of the class. (This was pre-Internet; good thing we had a decent reference library in the school.)

BTW, nuns don't like to be proven wrong - probably has something to do with the surgical removal of their sense of humor when they join a nunnery.

[BrokenPaw]

Hank,

It bakes their noodles just a little bit more when you tell them that sixteen ounces of gold weighs more than sixteen ounces of feathers, but that a pound of gold weighs less than a pound of feathers.

-BP

[Art Eatman]

I always preferred the term "aardvark" ounces, back when I was a vest-pocket bullion dealer.

Oh, well, 7,000 grains in a pound, so I can get 140 loads from a can of 3031 with a 110-grain bullet in an '06.  And a helluva lot more .38 Special loads when using Bullseye.

My only point, earlier, was that the decimal system was around long before anybody thought up metric measurements.

If you really want some fun, watch somebody try to figure out the distance between two points on a map.  The USGS maps come in several different scales.  Fortunately, there are "rulers" ("scales", in engineering-speak) which are scaled off to match the maps.

For instance, the commonly-seen 7-1/2-Minute Topographic Sheets are 1:24,000; 1" on the map = 24,000" inches on the ground.  24K inches is 2K feet, which is awkward whether you think in miles or klicks.  And "two-and-a-half inches, plus a smidgen" isn't a good way to measure a mile...

, Art

[Brad Johnson]

And "two-and-a-half inches, plus a smidgen" isn't a good way to measure a mile...

It's not!!?? Uh-oh...

Brad

[Art Eatman]

"Only accurate rifles are interesting."  Sorta the same way for measuring.  I note that an accurate measuring of angles can be very important, at times:  Don't get sloppy in a three-hour cross-country flight in your 172...

Art

[280plus]

Well, I know that won't be happening to ME anytime soon...

[280plus]

[gunsmith]

 
I love it when my threads do this, I am working in a machine shop, not really making a bundle or anything
but one of the guys sau
id if I stick around a little while and get plans, that he could probably
make an AR reciever out of any metal I like...he seems to think Titanium would be cool.
Plenty of gun friendly folks, and gear heads. Plus they are very patient with my lack
of  math know how.

[280plus]

The question is, after all this, can you read a ruler now?