denier (unit of measure)

Discuss word origins and meanings.
Post Reply

denier (unit of measure)

Post by tony h » Tue Aug 19, 2014 11:24 pm

Denier is a word that I have often just brushed over in its context. Today needing to find a supplier of 30 denier bonded nylon thread got me thinking.

The definition is oddly interesting and new to me: denier is the weight in grams of 9000 meters of the thread.
Which begs the questions: why 9000 meters and when was this defined?

I given up looking today in the forlorn hope of achieving some beauty sleep.
T
Post actions:
Signature: tony

With the right context almost anything can sound appropriate.

Re: denier

Post by Phil White » Mon Aug 25, 2014 10:00 pm

Missed this one. Wiki seems to have it all sewn up...
Denier /ˈdɛnjər/ or den is a unit of measure for the linear mass density of fibers. It is defined as the mass in grams per 9000 meters.[1] The denier is based on a natural reference—i.e., a single strand of silk is approximately one denier. A 9000-meter strand of silk weighs about one gram. The term denier comes from the French denier, a coin of small value (worth 1⁄12 of a sou). Applied to yarn, a denier was held to be equal in weight to 1⁄24 of an ounce. The term microdenier is used to describe filaments that weigh less than one gram per 9000 meters.

http://en.wikipedia.org/wiki/Units_of_t ... ent#Denier
Post actions:
Signature: Phil White
Non sum felix lepus

Re: denier

Post by Erik_Kowal » Mon Aug 25, 2014 10:32 pm

Phil White wrote:Wiki seems to have it all sewn up...
End of thread.
Post actions:

Re: denier

Post by tony h » Tue Aug 26, 2014 12:57 am

It still doesn't really explain why they use 9,000 metres. Would it not seem more logical to use 10,000 metres? Is 9,000 metres a conversion from some other unit.

There is a tentative relationship between the length of strand in a cocoon - somewhere 300 metres and 900 metres. Farmed silk is available in longer lengths.

Or am I being stupid and it is one gram that is the driver. One gram of silk is 9,000 metres and that becomes the base unit?
Post actions:
Signature: tony

With the right context almost anything can sound appropriate.

Re: denier

Post by Erik_Kowal » Tue Aug 26, 2014 3:03 am

That is curious indeed. My thought on reading your most recent posting, Tony, is that this would all make more sense if the weight of the denier coin (1/24 oz.) equalled the weight of a 9000-metre strand of silk, which in turn would equal one gram. However, 1/24 of an imperial ounce (a.k.a. the 'International avoirdupois ounce', equivalent to 28.3495 grams) equals not one gram, but 0.8465735 grams. Hence a none-too-trivial discrepancy of approximately 0.153 grams (i.e. just over 15%) needs to be accounted for as it relates to the denier unit of measure. In my opinion, this difference is too large to be brushed aside with the description "about one gram", as the Wikipedia entry does.

One difficulty with the definition contained in the Wikipedia entry cited by Phil is that it does not specify which kind of ounce is referred to. According to another of Wikipedia's articles, there are several different units of mass which go by that name.

Among the most plausible alternative candidates for the ounce referred to in the definition of the denier are the metric ounce (= 25 grams) and the French ounce (= 30.59 grams). Of the two, the metric ounce seems most likely; dividing 25 grams by 24 gives a weight of 1.0416 grams, a discrepancy of just 0.416%. Wikipedia's list of different types of ounce does not include any that is exactly equivalent to 24 grams; the metric ounce is the closest to that value.

According to Wikipedia's description of the original metric system, "In 1812 Napoleon introduced a system known as mesures usuelles which used the names of pre-metric units of measure, but defined them in terms of metric units – for example, the livre metrique (metric pound) was 500 g and the toise metrique (metric fathom) was 2 metres." Perversely, however, Napoleon's mesures usuelles defined his ounce not as 1/20 of a metric pound (which would thus have been 25 grams), but as 1/16 of a metric pound (= 31.25 grams).

A table from an MIT research paper (page 2, Table 1) gives coefficients for the variation in diameter of unprocessed silk thread that range from 14.8% for spider silk to 24.8% for silk produced by the Bombyx mori silk moth.

So although Wikipedia's equivalences across the units of measurement of mass are more than a little ragged at the edges, these inconsistencies are easily equalled or exceeded by the diametrical variation (and presumably, a corresponding variation in grams per metre of length) that exists in natural silk. However, such variations would be largely eliminated in the manufacture of commercial thread from the silk produced by the respective arthropod species.

As to when the denier became a standard for the measurement of silk, Wikipedia states, "In France, since the 15th century silk production has been centered around the city of Lyons where many mechanic (sic) tools for mass production were first introduced in the 17th century". One may assume that with the mechanization of silk production and the ability to standardize (and maintain) manufacturing specifications, it became possible to know what length of silk thread could be expected from a given weight of it.

According to another Wikipedia article, "The denier [coin] was minted in France and Italy for the whole of the Middle Ages, in countries such as the patriarchate of Aquileia, the Kingdom of Sicily, the Republic of Genoa and the Republic of Siena, among others".

Dictionary.com defines denier as "any of various coins issued in French-speaking regions, especially a coin of France, originally of silver but later of copper, introduced in the 8th century and continued until 1794".

But from the Encyclopaedia Britannica article which describes the evolution of the denier coin, it is apparent that like the ounce, one term was used to cover many different entities. In the course of its history, the characteristics of the denier changed considerably in every respect, including its metallic composition, its dimensions, its weight, and its equivalence to other units of currency.

According to Wikipedia's article on the history of the metre, that unit was first defined in 1795 as part of a reform of measures of length that followed the French Revolution of 1789.

The inference I draw from all this is that the denier unit of measure emerged after 1795 but before 1812. This is because only by then had all the units included in the definition been defined (if my assumption is correct that the ounce used in the definition of the denier is the metric ounce); the ounce incorporated in Napoleon's mesures usuelles had not yet been introduced; and the denier coin had only recently been withdrawn (specifically, in 1794 if Dictionary.com is to be trusted).

Nevertheless, a more reliable and authoritative source than Wikipedia will be required to establish exactly who defined it, when they defined it, in what context, and the reasons for their selection of the criteria used. And it is quite possible that I have made at least one incorrect assumption along the way; if so, I'd welcome more accurate information.

Researching this topic has certainly proved to be an instructive exercise regarding the limitations of definitions, the clarity or reliability of various sources of information, and the care that must be taken when drawing conclusions from secondary sources.

End of thread.
Post actions:

Re: denier (unit of measure)

Post by tony h » Fri Aug 29, 2014 8:55 pm

Very well summarised Erik.

I am not coming up with anything more on the internet so I have decided to ask at one of the museums/universities. I will let you know if I get a useful reply.
Post actions:
Signature: tony

With the right context almost anything can sound appropriate.

Re: denier (unit of measure)

Post by Erik_Kowal » Fri Aug 29, 2014 10:02 pm

Thank you, Tony.

After sifting through so much shape-shifting evidence, I would certainly find it gratifying if you are able to point to some definitive information about the origins of the denier and the basis on which it is calculated.
Post actions:

End of topic.
Post Reply