Leading us to the 18th century

Martin Vlietstra, one of our regular contributors, offers his thoughts on an early pronouncement by the newly-appointed Leader of the House of Commons.

When he became Leader of the House of Commons, Jacob Rees-Mogg sent a detailed style edict for his departmental staff. The final point of the edict, “Check your work”, is eminently sensible; the point about double spacing after full stops is dubious – in today’s world most word processing packages look after this; the point about using the post-nominal “Esq” for “untitled” men is considered by many as archaic, while the demand that the imperial system of units be used is not only contrary to UK law but is also plain ridiculous. This article deals only with his requirement to use imperial units.

The Guardian records Mr Rees-Mogg as having the nickname “the Member [of Parliament] for the eighteenth century”. Since the imperial system only dates from 1824, I will give him the benefit of the doubt and for purposes of this discussion, allow the eighteenth century to run up to the end of the lives of any British monarchs who were born during the eighteenth century (ie start of Queen Victoria’s reign).

The metric system of today, or more correctly the International System of Units or SI, is based on seven base units, five of which describe quantities with which most adults are familiar. The five are time, length, mass, electric current and temperature.

When the imperial system was introduced in 1824, it covered only quantities that were based on the imperial yard and the avoirdupois pound. By implication the degree Fahrenheit and the second became accepted as part of the imperial system, though, as far as I am aware, there was never any legislation stating as much.

The observant reader will notice that electric current has been omitted from this list. If Mr Rees-Mogg demands that only imperial units be used, how does he intend specifying quantities related to electrical appliances? He could start by specifying power and energy consumption in imperial units, after all one horsepower is equal to 0.7457 kilowatts and 1000 British Thermal Units are equal to 0.2931 kilowatt-hours, but that is about as far as he will get.

Power is defined as the rate of energy transfer; it could be the rate at which electrical energy is transformed into heat energy and/or mechanical energy; it could be the rate at which chemical energy stored in a piece of wood or coal is transferred into heat energy by burning; it could be the rate at which nuclear binding energy is transformed into electrical energy in a nuclear power station. The SI unit of power is the watt and the SI unit of energy is the joule (both named after Britons, observant readers will note). This is regardless of the source of the energy. In the imperial system, thermal energy is specified in British Thermal Units (BTU) or therms (100 000 BTU), while mechanical power is specified in horsepower. Unlike the metric system where one watt is one joule per second, there is no simple relationship between BTUs and horsepower.

Why have imperial units never been used for electric current, electrical resistance or potential difference (voltage)? The answer is quite simple – at the 1881 International Congress of Electricity in Paris, a degree of agreement was reached on the names and magnitudes of various electrical units and the following year, the British Association for the Advancement of Science, using work done by Thompson (later Lord Kelvin) and Maxwell, tied up the definitions by linking the electrical unit of power to the mechanical unit on power when expressed in metric units. At the 1893 Congress, held in Chicago, various governments were represented as well as scientists who worked in the field. As such, the confirmation of the definition of electrical units adopted by the congress, much of which was based on the work of the British scientists Thompson and Maxwell, was passed into law in many countries.

Mr Rees-Mogg might request that the temperature in his office be defined in degrees Fahrenheit, named after a German scientist, but he has a problem here – I have not seen a thermostat (at any rate an electro-mechanical thermostat) that has Fahrenheit in years and for good reason too – a room with a temperature of 60 to 70°F is comfortable, but a hot water system with a water temperature of 60 – 70°C could be dangerous. If one is not alert, one could find oneself in hot water (literally). Possibly Mr Rees-Mogg does not deal with mundane things like with hot water systems so he might be unaware of this.

Given her husband’s promotion (and increase in prestige), however brief it may be, Mrs Rees-Mogg might like a new kitchen. There are many modular systems around, but they are all based on modules of 500 mm (1′-7.7″ or 1′-7 2/3″) and 600 mm (1′-11.6″ or 1′-11 5/8″) inches. Trying to calculate the combined length of a larger and a smaller unit in inches will be cumbersome, but again, Mr Rees-Mogg might delegate this to a kitchen fitter. Moreover, any built-in ovens, fridges or dish-washers are designed around these modules.

We must of course be thankful that Mr Rees-Mogg has not fallen back on on his classical education by promoting the Latin language (in use in England and Wales for fifteen centuries after the Roman conquest) and Roman numerals – this system of units predates the introduction of the Arabic numeral system and decimals into Europe and as such the quantity 1′-7 2/3″ would have been written in medieval times as “i foot, vii inches and viii lines”. (Note – the representation of fractions in Roman Numerals is very cumbersome).

Readers too may have thoughts on what retro measures they might support if they became Leader of the House: cars to be preceded by a person with a red flag unless drawn by horses, new houses to be thatched, second and third class carriages to be reintroduced on the railways, ….

16 thoughts on “Leading us to the 18th century”

  1. I wonder how many of JRM’s departmental staff would rather use metric units in official documents (and would use the system). After all, does not the government still use metric units for official purposes?

    Hopefully one day common sense reigns and a future government will have the political will to finally finish metrication, which would be 60, 70 or so years after the start.

    Or if there is no deal, which the MP for the 18th Century himself and members of the current cabinet favour, this could result later in Scottish and Welsh independence and Irish reunification – in this scenario, hopefully the English, Scottish and Welsh governments would have the political will to finish metrication. A reunited Ireland would surely finish metricating the north.

    A correction, if I may: It is actually the Indian numeral system (it is not the “Arabic” numeral system, though Europe did start using the Western Arabic variant of the numerals themselves). The numeral system, the number 0 and the decimal placement system were invented by mathematicians in India.


  2. Yes let’s be global Britain, by using measures no one uses anymore.


  3. This is all in keeping with those who are hell-bent on maintaining the metric muddle alive and well instead of ditching Imperial and using SI exclusively.

    I know I have repeatedly flogged the BBC for constant use of Imperial even in places where you would expect only metric but this article is yet another flagrant example:


    This is a science article (traditionally one where metric should reign supreme) on top of which the scientist being quoted in the article himself used metric only. Yet the BBC could not resist adding Imperial in parentheses after all but one instance of some quantity cited in the article.

    This is truly shameful at this point in the 21st century after so many years since the UK officially launched itself into converting to metric.

    The Queen should insist that the muddle be tossed immediately into the dustbin for the good of the kingdom! That would shows Rees-Mogg and his ilk how things should go! 😉


  4. Well Ezra, flogging the BBC does no good. The BBC is not a thinking person who makes choices. It’s an inanimate entity. There is a person or persons with the power to make decisions somewhere in the organisation that is making these decisions. Either they do it for personal reasons or because they are compromising because they have been bombarded with letters and comments by Luddites who insist they use imperial.

    The queen isn’t gong to get involved. The only way for this to end is for the Luddites to disappear and in time they will.


  5. I would imagine that the biggest problem that JRM’s office now have is using the photocopier now that they are banned from using A4 and A3 paper.


  6. Thank you Tim. When I wrote the article, I quite forgot about paper.

    Would Mr Rees-Mogg prefer 11 inch by 8 inch paper, or would he prefer foolscap paper (13 inch by 8 inch)? Neither are readily available anywhere in the United Kingdom – one of the advantages of metrication was to replace two product lines with a single product line, and moreover a product line that was used elsewhere in Europe. BTW US letter paper won’t do as it is 8.5 inch by 11 inch and US legal paper is 8.5 inch by 13 inch.


  7. Martin,

    What about someone who makes coffee or tea from a metric sized container purchased in a local shop? Say a 500 g size with no imperial markings at all? What about other products that one may purchase, such as sweets where the size is beautifully marked in grams or litres?

    What if one is listening to a radio broadcast and the weather is reported and the word Celsius or pascal is heard through out the room? What if someone is talking to a colleague about the new movie 47 metres down and blurts out the word metre for all to hear?

    One way to subtly ignore the ban is to refrain from using any measurements at all. If asked how long something is state it in Double Decker Bus lengths.


  8. @Daniel “One way to subtly ignore the ban is to refrain from using any measurements at all.”

    Unfortunately I think that is indeed what happens in (on) UK TV media most of the time.
    With civil servants though, I feel they will probably ignore the ‘helpful advice’ whenever possible.
    A few years ago the then transport minister Philip Hammond gave a similar edict on using miles to contractors, then brought in the dual metric height and width signs.


  9. @Daniel this really is part of the problem rather than the solution.

    You only need to go to small shops and market stalls all over the UK now to see items that really should be weighed (such as fruit and vegetables) being sold by the bowl to avoid being prosecuted for pricing in imperial and not bothering with metric pricing.


  10. You’re right Alex. But, I’d rather see school bus lengths and bowls over an imperial holdout. I prefer these obscure references to pounds and yards.


  11. So is JRM only doing this because of the trade deal we are trying to get with the US? Sorry to break this to Jacob, but the US does trade with metric countries and also uses metric along side US customery units, which by the way is not the same as imperial units.


  12. Lee,

    A trade deal with the US will be a disaster. The US will only make deals with those countries it wants to have the upper hand. England may find itself forced to abandon whatever remnant imperial is still used and adopt USC. England will also have to accept GMO modified foods and other nuances that it presently does accept. Who knows, the US may even require England to drive on the right in order to sell US cars there without having to switch the interior.


  13. Daniel,
    A trade deal won’t be a disaster because by the time we get one the US will have a different president and trade deals take years to negotiate.


  14. Marching straight into the 18th century today, looking at air conditioning!!

    The Btu in adverts seems to be pretty universal, I do wonder if anyone knows what that is.
    I have responded elsewhere on these pages to a heating bod that thinks ‘everyone knows what a Btu is’, so OK, excluding HVAC personnel, how many out there know, use and understand these gas mantle era units? Second, how many out there still do not understand a kW?

    TBH this sort of intransigence is getting beyond a joke to me, just downright obstructive and annoying.


  15. US trade will hit a snag with units. As I understand from American posters, USA does not (yet) allow metric only labelling.
    If UK is to re-start dual labelling for the American market (rejoicing for some) then we do indeed run into the problem of different measures for at least the fluid products. This may be a bit of a bitter surprise for some as this fact is not widely understood (as if any of it was understood anyway)! Interestingly the US pint is smaller, but the US fluid ounce is larger, so we (UK) have a bit of a pint sized problem. There may be some legal issues arising somewhere.


  16. Brian,
    To me a BTU is equal to a kilojoule. The HVAC industry is a real mess. From my experience being in air conditioned buildings including homes, the air conditioners are very often incorrectly sized. On very hot days the air conditioners run almost constantly and never get the building to the right temperature. When being sized, they don’t often account for extra heating produced in the building, such as from stoves for cooking or even body heat from individuals working. They are calculated strictly on the cubic dimensions of the room they are intended to cool. Part of the problem may be the unfamiliarity with what a BTU really is.

    The BTU (actually it should be BTU/h) is a unit that is used as a means to make the air conditioner look impressive. Instead of X.X kW, you have XX XXX BTUs. All those digits in the values are a marketing necessity if you want to make you product look like it is a beast. The air conditioning personnel get so caught up in their own propaganda they are clueless as to how to size the products properly.


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