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Sigurd
04-27-2008, 06:57 PM
This thread is for people to post distances and or space measurements from life and art.

I often find when I'm setting a scale or reading a map that I'd like a rule of thumb for what the numbers mean. This is for posting what you think is significant. If we can I'd like to keep this thread on target. If not we'll have to collect any posts at the end.

-Sigurd.

Sigurd
04-27-2008, 07:10 PM
Basics:

1 mile = 1.609 km
1 km = 0.6214 miles

Acre - One acre comprises 4,840 square yards or 43,560 square feet (which can be easily remembered as 44,000 square feet, less 1%). Because of alternative definitions of a yard or a foot, the exact size of an acre also varies slightly. Originally, an acre was a selion of land one furlong long and one chain wide. However, an acre is a measure of area, and has no particular width, length or shape.
Wikipedia (http://en.wikipedia.org/wiki/Acre)

Chain - A chain is a unit of length; it measures 66 feet or or 22 yards (20.1168m). There are 10 chains in a furlong, and 80 chains in one statute mile. An acre is the area of 10 square chains (that is, an area of one chain by one furlong). The chain has been used for several centuries in England and in some other countries influenced by British practice.
Wikipedia (http://en.wikipedia.org/wiki/Chain_%28unit%29)

Furlong - A furlong is a measure of distance in imperial units and U.S. customary units. It is equal to one-eighth of a mile or 660 feet or 201.168 metres.
Five furlongs are approximately 1 kilometre (1.00584 km to be exact). Since the original definition of the metre was one-quarter of one ten-millionth of the circumference of the Earth (along the great circle coincident with the meridian of Longitude passing through Paris), the circumference of the Earth is about 40,000 km or about 200,000 furlongs.
Wikipedia - Roman Origins (http://en.wikipedia.org/wiki/Furlong)

Hectare - A hectare (symbol ha, pronounced /ˈhɛktɛər/) is a unit of area equal to 10,000 square metres, or one square hectometre, and commonly used for measuring land area. A 100 m square is one ha. Its base unit, the are, was defined by older forms of the metric system, but is no longer part of the modern metric system. The Comité International des Poids et Mesures classifies the hectare as a unit that is accepted for use with SI.
Wikipedia - Metric & Imperial (http://en.wikipedia.org/wiki/Hectare)

League - A league is a unit of length or area long common in Europe and Latin America, although no longer an official unit in any nation. The league most frequently expresses the distance a person, or a horse, can walk in 1 hour of time (usually about 3.5 miles or 5.5 kilometres).
Wikipedia (also info on Roman Measurements) (http://en.wikipedia.org/wiki/League_%28unit%29)

Midgardsormr
04-27-2008, 07:14 PM
Chain - Sixty-six feet. Ten chains to the furlong, and 80 chains to the mile.

Sigurd
04-27-2008, 07:27 PM
These measurements are taken from this map (http://upload.wikimedia.org/wikipedia/en/5/59/Middle-earth.jpg) which is clear but perhaps not authoritative. If someone has a better source post or PM me.

All measurements are straight distance, as the crow flies.

Brandywine Bridge to Mount Doom
= 333.6 Leagues
= 1167.7 Miles
= 1835 Km

Minas Tirith to Minas Morgul
= 18.7 Leagues
= 65.5 Miles
= 102.85 Km

Edoras to Minas Tirith
= 98.2 Leagues
= 343.7 Miles
= 540.1 Km

Sigurd
04-27-2008, 07:54 PM
The island of Great Britain encompassing England, Scotland and Wales - 80,820 sq.mi
Kansas - 81,820 sq. mi.
Minnesota - 79,620 sq. mi.
World Factbook - Includes 2008 est pop (https://www.cia.gov/library/publications/the-world-factbook/print/uk.html)

Prince Edward Island - 2,195 SQ MI , 5,683.91
139,089 residents (Wikipedia 2008 )
Wikipedia - PEI (http://en.wikipedia.org/wiki/Prince_Edward_Island)

Gibraltar - 2.642 sq mi, 6.5 sq. km.
Pop: 28,875 (Wikipedia 2008 )
CIA Workbook (https://www.cia.gov/library/publications/the-world-factbook/print/gi.html)
Wikipedia (http://en.wikipedia.org/wiki/Gibraltar)

Lichtenstein - Europe's fourth smallest state with an area of approximately 100 square miles. The total population is 28,000 of which 18,000 are citizens of the Principality.

RPMiller
04-27-2008, 09:04 PM
I really wish the world (read that as the US) would just stop fooling around and adopt the metric system and dump imperial measures. It would be so much easier not to mention accurate.

Sigurd
04-27-2008, 09:36 PM
RPMiller - I completely agree. Seems the US finds learning from the rest of the world a sign of weakness or failure.

btw. You posted - you owe the thread one interesting measurement :)

RPMiller
04-28-2008, 01:33 AM
From ocean to ocean (ie. San Diego, CA, USA to St. Simons Island, GA, USA), the shortest travel distance I found is 2,316.5.

NeonKnight
04-28-2008, 11:22 AM
I'll post my interesting measurement as a puzzle:

If you have a rope long enough to wrap around the equator of Mars, how much longer must the rope be to allow a 6 Foot tall man to walk underneath it all the way around?

Midgardsormr
04-28-2008, 11:34 AM
r = radius of Mars in feet
C1 = circumference of Mars in feet
C2 = new length of rope in feet
pi = 3.14159
L = additional length of rope necessary.

C1 = 2 * pi * r
C2 = 2 * pi * ( r + 6 )

C2 - C1 = L

Equatorial radius of Mars = 3396.2 km = 11142388 feet

C1 = 70009629 feet
C2 = 70009667 feet

L = 38 feet.

That doesn't seem long enough. Maybe I'll recheck my math...

edit: No, I'm right. C + x = ( 2 * pi * r ) + ( 2 * pi * ( r + x ) ) That's kind of strange; you'd think it would be much bigger.

NeonKnight
04-28-2008, 11:53 AM
Nope, you got it, it's not that long is it? People think it needs to be really long, like miles, but only a mere 38 feet.

Infact it doesn;t matter what the Circumference is. Mercury, Pluto, Jupiter, etc, it always will be 38 feet ;)

RPMiller
04-28-2008, 12:04 PM
Isn't it the length of a parabola with an amplitude of 6' that you are actually measuring? I seem to remember this question in my high school trig class.

NeonKnight
04-28-2008, 12:36 PM
Isn't it the length of a parabola with an amplitude of 6' that you are actually measuring? I seem to remember this question in my high school trig class.

Nope, it's circumference.

Observe in the following diagram where we start with a Circle of only radius 6. Each time we increase the radius by 6 feet, the circumference only oncreases by about 37.7 feet.

ravells
04-28-2008, 12:38 PM
It would be smaller if the man could limbo dance his way around Mars.

töff
04-28-2008, 01:01 PM
I really wish the world (read that as the US) would just stop fooling around and adopt the metric system
...I completely agree. Seems the US finds learning from the rest of the world a sign of weakness or failure.The U.S. officially adopted the metric system somewhere around the 1930's, I think. But like many populaces, we use both in everyday practice. We buy Pepsi in 2-liter bottles but milk & gasoline in gallons. We measure the "grams of fat" and "mg of sodium" in a Quarter-Pounder (a McDonalds hamburger). We give a pint of blood but receive cc's of plasma. Our wrenches come in both "mm" and "in". Our speedometers show both kph and mph. Cocaine is sold on the street by the "kee" (kilo[gram]), but pot by the ounce or pound.

btw ... the day I can't buy a pint in a pub in Britain will be a day I shed a tear.

RPMiller
04-28-2008, 01:12 PM
I see. I was thinking of it in slightly different terms. The rope and the man stay taut against the planet. Something like this:

RobA
04-28-2008, 02:35 PM
On the topic of metric, I found this site providing a metric time-line:
http://lamar.colostate.edu/~hillger/dates.htm

-Rob A>

RPMiller
04-28-2008, 02:54 PM
Great find Rob! We are so close...

HandsomeRob
04-28-2008, 04:45 PM
One I use all the time when calculating scales:
1 degree of latitude = 69 miles (approx.) = 111 km (approx.)

Also, re: the metric system. Use the metric system all you want; I'll be sad the day the imperial system dies. Like your crazy uncle, it may not work as well but it sure has character. I like to design measurement systems for my conworld that have just as many irregularities and eccentricities.

-Rob

Redrobes
04-28-2008, 05:52 PM
Heres one that doesn't pop up much... a rood.
http://en.wikipedia.org/wiki/Rood

B.T.W I use google now to do a lot of measurement math. I guess most of you know but you can "search" for items like "3 miles in meters" and it generates the answers.

Hah, but it doesn't do roods !!! :D

ravells
04-28-2008, 06:18 PM
You know, Sid James would have loved your last post :)

Redrobes
04-28-2008, 06:51 PM
You know, Sid James would have loved your last post :)He would :?: (im having another of those dense moments it seems)

I came across the term from a puzzle so given that were into full on puzzle mode this month - have a go at it if you dare...

http://stuhasic.com/enigma/enigm023.htm

(See 7 across or 1 down !)

Oh and let me tell you this. a) Its a corker, and b) its bleedin difficult - its no namby pamby fill in the blanks sudoku type puzzle.

ravells
04-28-2008, 08:38 PM
I'm printing this one out.

delgondahntelius
05-02-2008, 04:53 AM
Here guys... try this little program... highly useful :)

RPMiller
05-02-2008, 11:17 AM
Hey! We use that at work! All the engineers and field service guys have that. They have to do a LOT of conversions as we deal with metric constantly and also do fluid dynamics and such. I can attest to that being a great tool.

ravells
05-02-2008, 11:35 AM
There's also an 'ell'. From here (http://legal-dictionary.thefreedictionary.com/Ell+%28unit%29)

ELL. A measure of length. In old English the word signifies arm, which sense it still retains in the word elbow. Nature has no standard of measure. The cubit, the ell, the span, palm, hand, finger, (being taken from the individual who uses them) varies. So of the foot, pace, mile, or mille passuum. See Report on Weights and Measures, by the Secretary of State of the United. States, Feb. 22, 1821; Fathom.

RPMiller
05-02-2008, 11:47 AM
Hm... "Nature has no standard of measure." But the metric system is based off the wavelength of light emitted by krypton atoms so that part of the statement isn't quite true though, we can't perceive it with our own senses so it that regard it is true. ;)

waldronate
05-02-2008, 12:19 PM
Hm... "Nature has no standard of measure." But the metric system is based off the wavelength of light emitted by krypton atoms so that part of the statement isn't quite true though, we can't perceive it with our own senses so it that regard it is true. ;)

The meter was orginally defined as one ten-millionth the distance from pole to pole. A completely arbitrary number based on one planet's diameter and a number system influenced by the fact that we happen to have 10 convenient counting digits. Plus it keeps changing. http://physics.nist.gov/cuu/Units/meter.html has information on the history of the meter. Anyhow, my point was that the meter is based on arbitrary decisions based on one subgroup of a random species on a random planet in a random star system in a random galaxy. Not what I would pick for a natural standard of measurement.

The closest thing that seems to be a "natural" measure of distance is the Planck length ( http://en.wikipedia.org/wiki/Planck_length ), which is derived from some of the fundamental constants of our universe. It's not a terribly convenient distance for normal use, though.

I think perhaps that I should get more sleep so that I'll be in a better humor.

RPMiller
05-02-2008, 12:24 PM
See, now your just being nit picky... ;)

Sigurd
05-02-2008, 04:29 PM
600 Miles
(I posted this to the world building section but it applies equally here. When we throw around numbers it helps to have mental images to pin them on.)

Washington DC to New York City is, according to google, 229 miles by highway. As the crow flies it might be roughly 200 miles. 1/3rd of 600 mls

Washington to Quebec City is likely about 600 miles as the crow flies.

London England to Berlin Germany is 684 miles by highway - 583 miles as the crow flies.

The isle of Britain is less than 600 miles nth-sth (548 ml. by my inaccurate google earthing.)

600 by 600 miles - 360,000 sq ml.

The land area of Germany is only 216,998 miles.
The land area of Britain (Scotland, England, Nth Ireland) is 152,112 miles

delgondahntelius
05-03-2008, 03:53 AM
Or... slightly smaller than texas :D

Midgardsormr
05-03-2008, 12:02 PM
Larger even than Texas, actually. TX is 262,000 sq miles.

But much smaller than Alaska, which is 572,000 sq miles.

For my own reference, I was looking at the "Four Corners" states: Colorado, Utah, New Mexico, and Arizona when I was working out my topography. I neglected to go back there before I did my settlements. Even so, considering the number of ruined cities I placed in Tawaren, I think my pre-plague population level would be about right, and a map of this scale wouldn't necessarily show smaller populations unless they were significant in some other way.

delgondahntelius
05-03-2008, 03:04 PM
True... I was estimating the distance up and down ... roughly 700 x 500 miles... sq distances that aren't in a neat box cause me anguish. Whenever I'm mapping out areas like these, I always keep a point of reference that I understand. This is almost always done by figuring distance between cities in the U.S. Since I spent four years driving a truck over the road, I've been to every one of the continental US states save for North Dakota. So for the 600 x 600 miles I equate the distance across as being a trip from El Paso to Dallas. Since I've driven that before (more than several times) I can then put down towns and cities and other features with some confidence.

:D

Midgardsormr
05-17-2008, 11:45 PM
I came across the term from a puzzle so given that were into full on puzzle mode this month - have a go at it if you dare...

http://stuhasic.com/enigma/enigm023.htm

I've solved it! And I even documented how I arrived at my answer, just in case anyone wants a hint.

GM's Apprentice
05-19-2008, 09:52 AM
For fantasy battlemaps:

1 "pace" = 5 feet

Since I wanted to depart from the "you enter a thirty-foot-by-thirty-foot" room descriptions, I decided to create a fairly equitable system where I just had to count map squares.

(A pace is the average distance the Sarat covered for his left foot to hit the ground twice while crossing a bridge in my campaign)

This also seems a lot more like it would be a guesstimate for characters. "You enter a room approximately six by five paces". It makes it easier to hide secret rooms in buildings. (If the players want to pull out their measuring-rope, they certainly can....)

rpgmapmaker
05-30-2008, 08:42 PM
I was doing a random search for map reasources and found this site... (www.indo.com) not sure if you all knew about this yet or not but I thought it was worth a link. (http://www.indo.com/cgi-bin/dist)

It is a location distance generator thing? (How far is it?)

----Search out put looks like this----
Distance between Oklahoma City, Oklahoma, United States and London, England, United Kingdom, as the crow flies:

4649 miles (7482 km) (4040 nautical miles)

Initial heading from Oklahoma City to London:
northeast (42.1 degrees)
Initial heading from London to Oklahoma City:
west-northwest (298.8 degrees)

Oklahoma City, USA:
Location: 35:28:01N 97:30:49W

London, England:
Location: 51:30:00N 0:07:00W
----------------------------------

-Chris

su_liam
05-31-2008, 01:42 AM
Ooh! That is sweet.