Why Are Motors Rated in Horsepower?

It is the prerogative of a country to decide which units of measure will be used or which unit of measure will be allowed for import.

dear

R U School student?

The motor is machine which works with Input as electrical energy unit of which is KW, convert it in to mechanical energy unit of which is H P (Horse Power)

NASCON

R U School student?

I am not talking on behalf of elect-ok. But, even if he is scholld student, he is right and you are wrong. You need to go to school again, in some other school, if your school has taught these things.

Electric motor input is in electrical form in watts and output is in mechanical form in watts.

I also get surprised, how we Indians behave like this ! Concepts of Indonesian are clear than you. Please read all the post very clearly and try to understand the concepts.

hahaha....

thank you GURU. Actually i have been working in Electrical Contractor about 4 years...start from Small House (residential) Contractor, now in Industrial Contractor.

I think this forum is very useful to share our knowledge......and to see how electricity installed in every different country...

Yes, definitely. In most countries motor rated power is given in kW. HP is still used in USA for historical reasons.

Cheers..........Codey

Learn all the acronyms, find out which country it was originated and you will understand why NEMA and ANSI use HP instead of kW.

Please check up, it is in one of the previous threads. It is just an convention (since a lot of people are still quite comfortable with HP rather than KW) -

To a lay man the 5HP pump is more meaningful than 3.7KW.

Since the motor is selected to drive the load and not the otherway around, the backward integration applies.

But now in SI units, we specify our loads in KW only and then the HP becomes redundant/confusing.

why call it hp? there is a very interest story. let me tall you all.

once upon a time, there was an engineer who was a friend of Farady, he invited motor by the secret paper given by faraday. one day faraday went to see his friend by horse, when he saw the strong machine, he asked how strong it is. and I hope to know. as see he ride a horse, his friend replied, ah, it has as strong force as three horse you ride. scince then people begine use HP for measuring the motor.

haha, is it interesting?

add score...

emc,

The reason people like the Inch, foot, lb gallon is because it scales to the human body much more than the metric system. My thumb is 1 inch wide; my foot is 1 foot. A foot scales to a human's height and an Inch scales to a human's hand. I know what a in^3 is by my thumb, and I know what a ft^3 is by my foot. I can therefore design with it. When I hammer a nail and space it 1 inch, I can use my thumb… I have no idea what a cc^3 is, nor a meter^3, let along what a N, kg or anything is because it has no connection to anything I use. People who design houses know what I am talking about…

The inch system is based on the mean polar radius. The original proposal for the Metric system was also the mean Polar radius...but there is a problem...First, the inch already had that idea taken, second, to get that mean radius you need an orbital satellite...and this is 1800's… That inch is found in the Giza...someone knew that measurement... how?...Moses?...Pharoah? By using the inch, you are saying..."God" (or at least Captain Kirk or NASA) existed 3-5 thousand years ago…politically incorrect...and the motive of the French was to tear down the old order...so they chose the arc length from the north pole to the equator running through…Paris and other French places, which they actually measured, and not exactly accurately…

The polar mean radius is the longest straight distance on earth (and is how you would characterize a planet, since the center of gravity and the radius…). It is the most stable distance due that it is the longest dimension, whereas the arc is not something anybody would use as a standard, unless you are a politician….

The polar radius (cubit/inch system), and arc length through Paris (meter system), are both divided into 1/10 millionth. The original meter is therefore 1/10 millionth of the arc length from the north pole to the equator, and a ("sacred") cubit (25 inches exactly) was divided into 1/10 millionth.

Another reason the inch system is MUCH better is that it can be made factored by 2, 3, 4 and 5, whereas the meter is only by 5. The reason the cubit is 25 is that 5 is an important number and good for stepping off distances while walking normally. The number 6 is 2x3, and the second is a 60 base number, and there are 7 days… The equator radius is 1000 years in feet…

Which goes to the central issue of INCH vs METER. The inch is earth/earth. The meter is politics/earth. Time is based on the rotation of Earth (at least it was). Ask why they did not make a minute have 100 seconds if making decimals is the reason. Because the reason for going with meters is political, NOT scientific. The inch can be mille-inch, kilo-inch, centa-inch, and can be expressed in decimal form just like the meter. The meter and scared cubit (25 inch) are analogous.

The reason we use a dozen is because it can be divided by 2, 3 and 4. 10 of something cannot be divided by anything but 5. If you have 12 friend, you can send them by 2, 3 or 4, but if you have 10 friends (or board members) you cannot divided up tasks in whole numbers.

Most people don't realize that the Romans used a gallon with 216 in^3, which is 1/8th of a cubic ft^3 (12^3=1728…/8=216). The Roman gallon was 6 inch x 6 inch x 6 inch. It was a size that was small and useful, and when you look into history, that is what was used…along with all the scale sizing…of building and ancient technology…history…is lost with the meter, and the "patterns" are lost in the numbers when we switch to the meter….

Last but not least, the inch system is much easier to remember. Nobody knows what a centi, deci, kilo, Giga, mega, or whatever is…go ask your wife or kids…unless you are an engineer or science guy. You have to remember two things to know what you have, which is NOT efficient.

So, if we as engineers were smart, and honest, we would use the inch system, and have the gallon have 216 in^3 and not 231 in^3 found in our queens wine gallons. Which reveals that the English were dunk from all the wine they were growing in England…(midevil global warming?)… Hmmm, and the French were totally out of control and their measurement system was completely irrational…I see a pattern here… (nothing changes). It is sometimes easier to change a system that is totally broken (the French system before the meter) than a system that is a little "drunk" and arbitrary (wine gallon).

We need to fix the Inch system and base it in the human experience, and not French (now EU) politics. The mean polar radius is the only neutral measurement on the planet that includes all nations, and not just French people. We need to take the garbage metric system and toss it in the political waste heap of all such "French" ideas based on ego, hubris, and totally unscientific notions… You cannot call yourself scientific and base your measurement system on an arch length…sorry but at the foundation, the meter system is a joke. It is now based on the frequency of…which is based on time, which is time is based on…what? What a total joke… Our so-called scientific system is a circular loop and totally unscientific!

So, we need a power measurement system that relates to a human. A human can get on a cycle and pedal at about 1/12^th of a hp. A human power "H" would therefore be 550 INCH-LB/sec, and not FT-LB/sec. In KW that is 0.11175 KW, or about 110 watts. How many people know what one human can produce in terms of power? Easy…1 H…

When you get in your car, you know how to relate it to you. A H= hp/12. Your 175 hp car has 2100 H power. Your car runs at highway speed on 1/10^th (17.5 hp) or about 210 human power. A really good car should run on about 100 H power (8.33 hp, 6.2 KW). The average Joe can understand Human power, but has zero idea what a KW is. Can we just stop the Metric insanity…please…. If you want people to save energy, put it into terms they can relate to, and not a kilowatt…what is that…a spray to kill bugs?

So, if you ask the average person what a KW-hr is, they would likely say it is one hour of swatting flies as fast as you can! Please, stop this arrogant nonsense called the Metric system… We are Humans, not a cows, monkeys, horses, or pigs…we are humans, and last I checked, monkeys, cows and pigs don't go shopping, drive cars, live in houses, or engineer things. When a monkey can do the math, then maybe we should have a "universal" system that includes other creatures found on this planet. Woop, I forgot, we do have pigs and monkeys running our governments…now I understand…Maybe we need humans in our governments again before they send us all into complete Depression and world war…

In the mean time, lets straighten out the inch system, which is a truly scientific system because it is based on the mean polar radius, and eject the metric system from this planet, along with all the monkeys and pigs in our governments…

So we go from converson from CuInch to Cu-ft with 12³ = 1728 multiplication instead of a round figure of 10³ ? to prove that we are not cows and....

Please also remember the SI system is not only in terms of the units but also it is a decimal system (ie the units are base 10),

Except the physical constants of course.

People who design houses know what I am talking about…

This is totally based on your architect's comfort. Over here our people are comfortable with some other units (and we too some times say that it is the best)

But end of the day the level of comfort is much higher for the SI system. and that is not for the units per se this is because of the unit convertibility factors.

Only the time and angles were not decimated due to historical reasons.

especially when you are going for complex calculations.

try Changing from Kg/m² to g/cm² it will be all in 10s

The same will not be when you do it with T/ft² to PSI.

Next are you going to say that since we are not cows we will like to have the multipliers and converters as complicated as possible .

SB,

Every claim of "comfort" that you claim with the SI system could be had with a meter=25 inch = cubit = 1/10 millionth of mean polar radius.

Why have the meter based on an arc? It makes no sense.

Ask yourself why Napoleon would spend all that money to measure the earth's arc? Was it a "bailout" jobs program? Why would the French not just adopt the inch which the English had and was used by the Romans (Italians, Germans) and others back to Giza?

The meter is a long distance. It is just a length. Why are you so against change? Change we can believe in...

By doing what I suggest, the English system would have been absorbed into the metric and we would not have an issue. If you want to decimaltize the measurement, use the cubit-meter, if you want to use inch, then use it. Tools could be made that seamlessly mesh. Weights would also be made common, and we would have ONE standard. Now all we have is an arc length as a standard...what a joke.

The French use the measuring system of their hated enemy the English, incroyable!

You forget nationalism is also a big factor to adopt a measurement system.

Both have their advantages and disadvantages.

Much has to do with what we're used to working with.

I have to deal with both because I do work for a French owned company.

That discourse is the largest heap of bovine excrement I have read in a long time.

Chas

I think your ego is getting in the way of actually understanding what you read, if you really did read the whole thing.

If you're going to disagree with someone that has produced a well written piece on the subject then you should be producing something of your own to support why you disagree with it.

Other then it being easier to do math by 10's, and that's about the only argument I've ever heard for justifying the metric system, there's nothing else that supports it.

Even metric nuts and bolts have to have Loctite put on them to keep them from coming loose. It's because of this that Theodore Roosevelt ordered having a standardized nut and bolt size system established, after taking over the endeavor of building it, because of the metric fittings on the Panama canal being such a problem with everything coming loose all the time and none of the nut and bolt manufacturers in the United States made nuts and bolts that would fit those made by another company.

So what do I do to measure a distance without any tools?

I can pace it out, one foot in front of another and easily estimate a mile, but then I have to multiply my number by 5/8 so I can tell you what it is in kilometers. It's inefficient.

I know how the French are by nature. I work with them and they are stubborn. You have a company there in Roda, Spain that I work for division in the United States called MAF Industries. We have a few French Nationals that work here that have told us that they prefer working with us more then they do other French because we are easier to work with and get things done.

I didn't know that loctite existed in Roosavelt's time!

I work with both metric and SAE threads. I have never had any issue with either coming loose when applied properly.

As for the argument about the mile versus the kilometre it holds no weight. Whether you pace out 1760 yards for a mile or 1100 yards for a kilometer the accuracy depends on your length of stride.

(ORIGIN from Latin milia, plural of mille 'thousand'; a Roman mile consisted of 1,000 paces (approximately 1,620 yards).

regards

Chas

Not sure how or why metric bolts come loose more or less than any of the other myriad of threads. I would be interested to hear.

It is even less clear to me what the preferences of French Nationals to working for or with people other than their own nationals has to do with this subject.

Nor, I must say, do I have any great need in my engineering profession to worry about how long your stride is if you have left your tools at home? Does not sound like a reason for maintaining a specific measuring system.

The Furlong, Firkin, Fortnight system comes to mind, and then there is rating beuty in Helens, one Helen (H) is enough beauty to launch 1000 ships, from which we get the

other units mH, and uH.

and then there is the L, a unit of reproductive power equal to one E(Engineer) times one H.

and a host of others in first year Engineering in 1958, most of which are scarcely printab;e

Aurizon,

You forgot to add in the metric system to the waste heap of measurement systems. Each system has a reason, which usually is to make the math easier, or scale something relative to some size so the a human can use it without a calculator.

What is the reason for the metric system? Politics?

It does not make the math easier, as I explained in depth above. It serves no purpose in science because it is not scientific, since no real scientist would use a system based on an arc, nor would they use one that has a circular loop of distance and time (definition of the meter is a function of time...), or would they use one that mixes three number base systems (60, 12, 10), and then claim it is simple. Most people don't even know what base anything is, let alone 60, 12, or 10. Can we get a grip here people???

Now we have kilo, mega, giga, tera in measurements of physical properties, in place of thousand, million, billion, trillion which are used in most other things, such as money and numbers in general, but when you use the EU mandated metric system you must learn some alien system...mega? giga? tera? Huh? What a load of garbage...and arrogance in the extreme.

Should we say that the bailout is 9.7 tera-dollars, instead of trillion-dollars? Or some friend of a congressman got 2 mega-dollars for their spotted howl research project? This metric system is insane....and it does not mesh with the English language, nor any other language, except French...ah, now we know... If you culture will be gone in 50 years make sure you force it onto people by legislation...

The Inch system is an ancient and universal system going back 4-5 thousand years when there was no such thing as English, French, German, American...get it? If you want to unite the world under one standard, why would you base it in France of all places. You would think that any country with one spec of self respect and honor would not adopt the arc length running through another countries territory. Maybe Indians should define their own meter running through the Himalayas, or from pole to pole instead of pole to equator, making it somewhat longer or short respectively...crazy as crazy gets....Sheeple in the extreme...

I don't know where guest is from, but I hope not from the USA - would be embarrassing. The metric prefixes are not French, they are of classical Greek and/or Latin origin, and they were universally understood in western civilization by educated people, who all learned Latin and/or Greek in school, back when the metric system was invented.

BTW, I am from the USA and don't espouse the metric system for everyday non-technical use in the USA, but it's the only way to go for science/engineering, and I am hardly alone in that assessment.

Guest made a few good points in his first post, which I acknowledged in my response to that post, but his obnoxious attitude does him no credit, and harms his cause.

Emc,

Latin? Where does French derive from? Who uses Latin? Japanese? No. Chinese? No. USA-- No. Why not make it so that each language can translate it into their own language via the universal language--math. Is that not the point of the 1000's etc? Japanese don't use 1, 2, 3... but math is universal in rules. Each language translates, then there is a true respect for other cultures and languages. The Metric system totally disrespects other cultures. If we keep it in math with a universal location (polar radius) then we include all, not just French "progressives" as they like to call themselves.

The point being is that the metric system was a political and cultural move, not a scientific move viable to ALL countries because of its construction.

Compare: Polar radius to arc radius... Polar wins because it is universal to all nations, makes common sense, has a well know relationship to a sphere and to the center of gravity. The arc is a part of many, not the core.

The time meridian should also not be in England, and should be on some remote small island where every nation of the world could "own" a piece of land along a longitude to call their own and to start the clock.

Since the meter was so inaccurately measured (off by 3%?) they could have just chosen 40 inches. But why not just choose the polar radius? Politics and anti religious notions, that's why. Read the history...

You can swap the meter for the "sacred" cubit (1/10 millionth of the polar radius) and get everything you have in metric system. You could then have all the so called benefits of the Metric system, and still have use of the inch standard. So why would they not do that? Such a move would have saved many trillions of dollars, or tera-dollars...could not resist...

Well did not because they would have to admit that ancient civilizations were MORE advanced than they were!

The theory goes that we "progress" over time, and the arrogant metric system designers were making a political statement of hubris and using our measurement system for their politics. They hijacked our very measurement system to make a statement against the old world!

The real world of reality is that civilizations progress and digress. The metric guys were saying that all their elders were dumb and the children (the metric guys) knew it all, just like the 60's generation has done to our horror...therefore we cannot use an established system in inches (sacred cubits), and nor can we use a Constitution... It is all the same PC arrogance, which makes me vomit.

Can we as CR4'ers just be honest about this and know the history?

By switching to the cubit (call it the "new meter"...like a "new deal" ) we would have instant world convergence of measurements old and new...peace. If their goal was as you say, that is what they would have done. Their goal, however, was not comfort, peace, ease of use, but revolution. Revolution... That was the goal, not science, not ease of use, just rank, arrogant ignorant revolution....politics by another means. The wanted to jerk people around with their inaccurate and arbitrary ways, just like the current politicians are doing. We call such people "tyrants" People love to get into power and make random decrees to show how important they are, and this is what is at the core of the metric system.

I say the we make the "new meter" equal to the old cubit (25 inches exactly) and have peace. Since the meter is now based on frequency, just change the number of waves. Because they were so far off in measuring the meter in their "enlightened" state, why don't we just do the switch? The meter has no foundation to it.

As for my obnoxious attitude, I find the metric system to be obnoxious at the core. It is time for a true "revolution" (rolling back) to occur. Off with the metrics head!!! We the people, needing a more perfect union of measurement systems, do hereby declare... Get the point. It is time to take the garbage out!!!!

Dear Guest,

some excerpts from the Oxford English dictionary:-

metre¹

(US meter)

• noun the fundamental unit of length in the metric system, equal to 100 centimetres (approx. 39.37 inches).

— ORIGIN French, from Greek metron 'measure'.

meter¹

• noun a device that measures and records the quantity, degree, or rate of something.

• verb measure with a meter.

— ORIGIN originally in the sense person who measures: from METE.

mete

• verb (mete out) deal out or allot (justice, punishment, etc.).

— ORIGIN Old English, measure;

I suspect from your allegiance to the sacred cubit you may belong to the funny handshake brigade. I wouldn't want you to do any masonry on my house as i think the foundations would be very shaky!

So it is "probably" French.　Bummer

It has been chosen as a standard, there is not always a logical reason why a standard is chosen, with Videotape VCC was better than VHS, HD-DVD Vs Blu-ray and so on, The most important thing about Napoleon is not that he choose "le metre" but that he made standardisation compulsive in his "Empire" thereby helping trade and technical advancement.

As you have remained a "Guest", though I would guess that you are a regular, I shall do the same. I have read your comments with great interest. I do however substantially disagree with you.

What I find disturbing is your apparently fervent belief in the correctness of the Sacred Cubit to the exclusion of a system that is embraced by a very large portion of the world population.

Wow, no chicken power here! Guest, please register so we can tear you down properly. BTW, the metric system is used in many US products. I don't care which system they use, but I wish there was only one. I have a lot of inch tools and cabinets full of inch bolts, and a few metric of each. It's disgusting to try to fit an inch Allen wrench into a metric bolt or strip the corners off a hex bolt because the socket set is a little to big.

that was the most needlessly lengthy and confusing reply to a simple question in the history of man/cows.

i understand how the imperial measurement system can be useful to those familiar with the quantities that it's based on. But these familiarities with common Imperial lengths / weights can only extend so far... Many engineering calculations contain quantities that are too large or too small to envisage in terms of everyday lengths or weights - the 'layman' won't know the difference between 204567239 lb and 92790138 kg... though they are identical. Same with 0.0039 in - try measuring that with your thumb! (its about 1mm, 10^-3 times a metre).

Engineers will know what i'm talking about.

though i guess in the end its just what you get used to!

dave

You are reading book, but Im making a joke. although I know it has something to do with horse.

but Watt's refinements actually kick-started the Industrial Revolution.

this point, you are right, steam engine had been invented many years ahead of Watt, till watt invented adjustor, the manchine had been put into safe, practice use.

You induced a topic of system. we all use MKSA system, I was told only your american still instead on inch system.

its unconvinient for us to convey them. because many software also use inch system, like pcb, etc. as well as electronic devices size. why your usa was so indenpendent.

This was all before the invention of the MKS - SI system of units. Note the modern unit of power is named after Mr. Watt. As others have posted, it is the prerogative of a sovereign nation to decide what units will be used. The USA has been trying for decades to shift from the English system (which the English abandoned decades ago) to the MKS-SI system, but our citizenry is just too set in its ways to respond. Myself included.

I understand, you conduct poles to decide the units. This I read in one of the editorials of Applied Optics in 1980s. Effectively you are still using FPS system, miles, inches, pounds/gallons etc. Here in India, people never noticed, when the units got changed. Now over last 30 years, even villagers use Kilometers and Kilograms.

I remember one documentory on Nation Geography about Air Crash Investigation: Pilot filled fuel assuming that the units of volume for fuel filling system are changed. So he filled XXXXXX units of fuel. According to his understanding, those were XXXXXX Kgs. But actually XXXXXX pounds of fuel was filled. Effect: Plane was out of fuel while still away from the airport. Please correct me, if I am not correct in putting the story, which I saw long back.

Because CP ( or more commonly known as " chicken power" ) just didn't have the right connotation to get the point across.

To further the discussion, the issue of choosing Watt's name as the SI was because being a name, it would be the same in any language and always abbreviated as W. "Horse Power" when translated became many different acronyms. That is why you sometimes see older machines with ratings such as CV, which was used for Latin based languages such as French, Italian, Spanish and Portuguese because of the word for Horse starting with C, or PS, which is German for Pferdestärke or "Horse Strength". It got too confusing.

But here in the US, we just have a hard time changing things to accomodate people on other continents.

Jr,

Try going to the EU and selling Inch based products. The EU is going to ban such the inch system in the EU. The USA is the most accomodating country in the world...give us your tired, poor...and crazy metric system... I get it...agree with the EU or you are not accomodating... Up is down, backwards is forwards... black is white... smoke and mirrors... got it...

Another reason is that the engineer providing circuits for the motor is interested in the max ampacity required of the motor which is given in KVA rather than KW. The motor tables list the motor in HP, Voltage and amperage. KW is an unused quantity.

Go to http://en.wikipedia.org/wiki/French_units_of_measurement and all will become obvious. Why should the French use the English measures when they had their own set of measures which were non standardised.

If we have to go to old English measures then lets do so. Banned will all mention of "city blocks", turning on a dime and anyone using of pounds (avoirdupois) above 13 will be severely castigated. (14lbs/stone). This will be in turn limited to 7st 13lbs whence it moves up to hundredweights (cwt).

The Dollar will have to be sacrificed on the altar of antiquity also, especially as this is a metric based quantity.

The liquid measures will have to be regulated so that the pint equals 20 oz and thus the gallon will weigh 10lbs.

Perhaps our Guest would like to go to the wiki article :-

http://en.wikipedia.org/wiki/Avoirdupois#American_customary_system which may dampen his desire for his customary units in light of his obvious xenophobia about the French.

regards

Chas

capblanc,

You seem to not have read my comments very well. It is NOT about France, French people, or the like, and I don't dislike them...both my parents spoke french...I learned french as a child to some extent, I now speak German...some Japanese, and my brother speaks Italian, my wife speaks Portugese, and I would love to learn many more languages and live in many different countries.

That said, the metric system is NOT universal, nor well thought out. It was because the French did their old system so randomly that people just said ok, bag that junk, and let's try this new metric system. The reason the "English" system, which was actually an old system that Europe used during the Roman empire, was able to stand up so long to the metric system was because it made sense in a large measure, and likely helped England usher in the industrial revolution, for without a reasonable system, like the INch system, little engineer was possible, or at least it is slowed. The furlong, and such things have been forgotten, as they should.

The central point is if you want a world system, then you should start with a standard that the world can agree on, and not something that favors one culture over another. What I propose would be ok with Chinese, Indians, Polish, and all nations as it was not something that is derived by one dominate (at the time) culture. By making the "meter" = cubit, then you can add in what works in the old Inch system and what works in the new decimal based "metric" system and then they are the exact same! But by making it based on the arc, the French forced a contention where none should have existed.

Do you want to combine the systems or not? I would suggest you stop mocking and first understand what I am saying...

Dear Guest,

I can read your posts but I cannot understand your hatred of the metric system. No system can be perfect. Ideally all the measures would tie together seamlessly with nice easy relationships between each entity but that is impossible due to the nature of the universe and the constants therein.

The metric system is a lot easier to use, and more importantly, has been adopted by more of the world as the standard than the customary units used in the US (and to a lesser extent, the UK). With a world population of 6.764 x10⁹ versus 306 x 10⁶ in the USA it is fairly obvious who is dancing out of step. You may say that not all of the world has adopted the metric system but by the same argument I would counter that the American academia has fully embraced the metric system and a sizeable proportion of the engineering community also.

The metric system is a live system, being modified by international accord as the technical needs dictate. The USA is a full member of the ISO organization and has a hand in setting the standards.

Jump down off your soapbox, dust away the cobwebs and get on with the realities of the this world. If you want to keep some quaint measures for keepsakes, the pint, an acre or whatever, then do so, but please don't try to convince anyone that imperial measures are a system of any kind.

Regards

Chas

Not meant as a specific answer to this post, but I thought this was a rather interesting introduction to a paper written in the 19th Century.

WEIGHTS MEASURES AND MONEY OF ALL NATIONS. COMPILED BY F. W. CLARKE, S.B., PROFESSOR OF PHYSICS AND CHEMISTRY IN THE UNIVERSITY OF CINCINNATI.

ENTERED, according to Act of Congress, in the year 1875

IN the following pages the compiler has sought to arrange, in a manner convenient for reference, the weights, measures, and money, of all nations. The work is naturally divided into two parts : first, a classification according to countries, arranged alphabetically; and, second, a set of tables in which the value of each unit is given both in English and in metric standards. This use of the metric system, coextensively with the ordinary system, may be regarded as the characteristic feature of the book. Of course, its introduction on so broad a scale doubled the labor of constructing many of the tables in the work, but the writer believes the labor to have been profitably spent.

The metric weights and measures are now legal in this country, and are used by at least twenty nations besides ; surely, then, they deserve as much attention as our own more locally familiar but more bungling systems. Our three sets of weights, our three different gallons, and our two dissimilar bushels, all unrelated to each other, or to the units of length, must soon give way before the simplicity and elegance of the metric system. That this event may soon happen, and that the weights and measures of the world may before long be reduced to metric uniformity, is the sincere wish and hope of the writer.

F. W. C.

Prof,

Do you have a link to the Clarke reference you cite?

Why would a rational person want a standard based on an arc length? Are you a professional and rational person? I assume you are, and invite you to first peacefully understand my points, and not to rush into wanting something that a rational person would not consider, namely an arc length as a standard.

The relationship between a meter and inch is 25 * PI/2 * EF (error factor). When the arc length going through France was measured, they were off an amount. The meter is therefore, not only inaccurate from its birth via a ground measurement, but is disconnected to all of history. The meter was adjusted to be equal to exactly 2.54 cm later on.

Set 1 inch = 2.54 cm (cm is now not legal, by the way) = .0254 m. One cubit =25 inches. 0.0254 *25=.635 meters

1 Cubit =.635 meter, exactly.

Multiply: 0.635 * 3.1415926… / 2 and you get .997455. The original meter was changed by 1.000000-.997455= 0.002544 to link both systems by the common factor of 2.54 cm.

Why bother with such nonsense? Why have a standard (meter) based on an arc?

Look, draw a circle, and divide it into four parts for four arcs. A full circle circumference is 2 * PI * radius. One fourth is the R* PI/2. The relationship between the meter and cubit is PI/2, or the relationship between the radius and the length of the quarter arc length. No scientist would base a foundational length on an arc length. Only a linear length would be allowed, and therefore the meter (quarter arc of the planet /10 million) should not be allowed...

It is NOT a matter of debate that an arc length standard is NOT rational. We hold these truths to be "self-evident" and fundamental to reason. The meter is not based in reason…

If you took the time to read my previous posts, you would see that by making the meter exactly =25.0000000….. inches, we could have had a common standard long ago, and that standard would have been 25 times an Inch, or a cubit. We did not realize this however, until after WWII. Newton himself looked into this matter...

All of your claimed advantages found in the decimal based meter can be found in a decimal based cubit that is renamed "meter," or measurement. The meter is political, and therefore not valid... Sorry...