English units of measurement
AMERICAN ENGLISH AND BRITISH ENGLISH
General ambiguity and vaguenessThe terms British English and American English are used in different ways by different people for different purposes. They may refer to: (1) Two national varieties, each subsuming regional and other subvarieties, STANDARD and NON-STANDARD. They do not extend beyond the frontiers of their states, but within those frontiers everything is included. (2) Two national standard varieties, each excluding the national non-standard varieties, but to some extent merging with at least some of these. Each is only part of the range of English within its own state, but the most prestigious part. (3) Two international varieties, focused on particular nations, but each subsuming other varieties in a more or less ill-defined way. Each is more than a national variety of English. (4) Two international standard varieties that may or may not each subsume other standard varieties. Each serves in a more or less ill-defined way as a reference norm for users of the language elsewhere. Furthermore, whether BrE and AmE are understood as national or international varieties, there is so much communication between them that items of language pass easily and quickly from one to the other, often without clear identification as primarily belonging to one or the other, or to some other variety.
Lexicographical ambiguity and vaguenessThe ambiguity of the terms is reflected in dictionaries. When a dictionary labels something BrE, users can safely assume that it has more currency in Britain than in the US, but cannot be sure whether it is restricted to Britain or is used elsewhere, as for example in Australia or New Zealand. Often enough, the lexicographer using the label does not know either. The vagueness due to the easy passage between the two varieties is also reflected in dictionaries, by the tendency to qualify the labels with some such word as chiefly or especially, a tendency that appears to be increasing as communication between AmE and BrE increases: the 1st edition of the American Heritage Dictionary (1969) used both British and Chiefly British as labels, but the 2nd (1982) uses Chiefly British only. The use of qualifiers with BrE and AmE is in sharp contrast to their non-use with labels of certain other types: an item may be labelled Slang or Archaic, but not *Chiefly slang or *esp archaic. An item labelled Chiefly BrE or esp BrE is not more likely to be used in, say, Australia: it is more likely to be used in the US. Similarly, an item labelled Chiefly AmE or esp AmE is not more likely to be used in, say, Canada: it is more likely to be used in Britain. In this respect, qualifiers like Chiefly and esp loosen the national restrictions on BrE and AmE, but do not affect their international range, which is already rather ill defined.
National standardsIn the following discussion, the emphasis is first on AmE and BrE as two national standard varieties and then on their differences rather than their similarities. Paradoxically, the desire for a discussion of British/American differences reflects an underlying confidence that the similarities between them are greater: even if Americans and Britons are said to be ‘divided by a common language’, the language remains essentially common, especially in terms of standard usage. The two standard varieties are contrasted below in terms of spelling, pronunciation, grammar, vocabulary, and idioms.
SpellingMost spelling differences between BrE and AmE do not signal differences in pronunciation. Rather, they serve as emblems or shibboleths of linguistic nationalism. It is primarily spelling that indicates whether a text is British or American in origin. By and large, the adoption of certain spellings in AmE has impeded their use in BrE or hastened their decline if they were used in that variety: such AmE -or spellings as color were once freely available alternatives to -our in BrE. However, when spelling is ‘normalized’ to one or other print standard, it may no longer be possible to identify the source of a text. It was once common to change the spelling of American books published in Britain, but in recent years the practice has been less common. This may mean that British linguistic nationalism is waning, or simply that the practice costs less, but since it also makes American texts easier to identify in British editions, it may slow down the adoption of expressions and constructions identified as AmE in those texts. There are two ways in which the orthographic differences can be classified: systemic or non-systemic; exclusive or non-exclusive:
1. Systemic or non-systemic differences.If a difference is systemic, it affects large classes of words; if non-systemic, it affects only one word or a small group of words. By and large, the difference between BrE colour, AmE color is systemic, affecting such words as hono(u)r, favo(u)r, neighbo(u)r, vigo(u)r (but note languor, stupor, torpor, etc., in both varieties). The BrE variant gaol (by contrast with the common jail) is non-systemic, affecting only one word and its inflections (gaols), derivatives (gaoler), and compounds (gaolbird). Occasionally, variants exist in both varieties: the optional e in abridg(e)ment, acknowledg(e)ment, judg(e)ment can be found in both AmE and BrE.
2. Exclusive or non-exclusive differences.When writing colo(u)r, either a BrE or an AmE spelling must be chosen; there is no international alternative. In the case of gaol/jail, however, there is a choice between local gaol and international jail. In the case of ax(e), an international variant axe coexists with an ax that is now AmE, though it was once used in BrE: in 1884, the Oxford English Dictionary favoured this spelling, but in 1989 the 2nd edition has changed to axe. There seem to be no cases of an international spelling variant coexisting with a marked BrE variant on one side and a marked AmE variant on the other.
All permutations and combinations of the two categories are possible: colour/color, systemic exclusive variants; the suffixes -ise/-ize, systemic non-exclusive variants in BrE; gaol/jail, axe/ax, non-systemic, non-exclusive variants in BrE and AmE respectively; in banking, cheque/check, non-systemic exclusive variants. Among the principal systemic variants are:
1. The colo(u)r group.Most words of the type color/colour are from Latin or French: arbo(u)r, armo(u)r, endeavo(u)r, favo(u)r, flavo(u)r, hono(u)r, humo(u)r, labo(u)r, odo(u)r, rigo(u)r, savo(u)r, tumo(u)r, valo(u)r, vigo(u)r. In Latin, their forms are uniformly -or (arbor, odor) and in Modern French their cognates may have -eur (couleur, honneur). Some, however, are Germanic in origin (harbo(u)r, neighbo(u)r) and seem to have picked up their u by analogy. The BrE u is not used in words, other than neighbo(u)r, that readily refer to people: actor, author, emperor, governor, survivor, tenor are the same in both varieties, though especially during the 16–17c such spellings as emperour, governour occurred. In such cases, the -or is generally interpreted as an agent suffix like the vernacular -er: author is as invariable in its spelling as writer. There are, however, a number of anomalies: such words as error, mirror, pallor, terror, tremor have no u in BrE, and in AmE the spellings glamor, savior, savor are nonexclusive variants, coexisting with the international glamour, saviour, savour. Saviour appears to be the last surviving -our agent suffix referring to a person. In AmE, the colo(u)r group has -or-in its inflections (coloring), derivatives (colorful, coloration), and compounds (color-blind). BrE derivatives are more complex. Before vernacular suffixes, the u is retained: armourer, colourful, flavoursome, savoury. It is also kept before the French suffix -able: honourable. Before Latinate suffixes, however, it is dropped: honorary, honorific, humorous, humorist, coloration, deodorize, invigorate. In such cases, AmE and BrE spellings are the same. Even so, there are some residual anomalies: BrE keeps the u in colourist and AmE can have the u in savoury and appears to be more likely than BrE to have a u in glamo(u)rize and glamo(u)rous.
2. The centre/center group.In words of this type, BrE has -re and AmE -er, and the difference is exclusive. The chief members are of non-Germanic origin and are: centre/center, fibre/fiber, goitre/goiter, litre/liter, meagre/meager, mitre/miter, sabre/saber, sombre/somber, spectre/specter, theatre/theater. The agent suffix -er (as in writer) and comparative ending -er (as in colder) are unaffected. Many words in both varieties have -er (banter, canter) and -re (acre, lucre, massacre, mediocre, ogre). In the case of the second group, an -er spelling would suggest a misleading pronunciation (therefore no *acer, *lucer, etc.). BrE distinguishes metre (unit of measurement) from meter (instrument for measuring; prosody), but AmE uses meter for both. Though theater is the preferred AmE spelling, theatre is common as a part of a name. Generally, the differences are preserved in inflections (centred/centered) and compounds (centrefold/centerfold), but usually vanish in derivatives through the loss of the e, which is no longer pronounced (central, fibrous, metric/metrical, theatrical).
3. The (o)estrogen group.In words of Greek origin (in which an original oi became a Latin ligature æ), BrE has oe in exclusive variants, AmE e or less commonly oe, typically in non-exclusive variants: am(o)eba, diarrh(o)ea, hom(o)eopathy, (o)esophagus, (o)estrogen, (o)estrous. The differences are maintained in all inflections, derivatives, and compounds. Two words of Latin origin have been assimilated into this class, f(o)etus and f(o)etid. In both varieties, all trace of the earlier oeconomy, oeconomical, oecumenical has gone (in economy, economic/economical, ecumenical, etc.). Within a word, (o)e is pronounced /iː/ in both varieties; at the beginning it is pronounced /iː/ in BrE and may be so pronounced in AmE, though e tends to be pronounced /ɛ/. The pronunciation of BrE oestrogen is therefore ‘ees-’, of AmE estrogen is generally ‘ess-’.
4. The (a)esthete group.In words of classical (ultimately Greek) origin in which a Neo-Latin æ passed into English as æ then ae, BrE has tended to keep ae as an exclusive variant and AmE has had e and ae as non-exclusive variants: (a)eon, arch(a)eology, gyn(a)ecology, (a)esthetics, an(a)emia, encyclop(a)edia, h(a)emophilia, h(a)emorrhage, medi(a)eval, pal(a)eontology. The spelling differences are maintained in inflections, derivatives, and compounds. In the case of (a)esthete and its derivatives, the spelling can signal a difference in pronunciation: beginning in BrE with /iː/, /i/, or /ɛ/ and in AmE with /ɛ/. Elsewhere in this class, however, (a)e is pronounced /iː/ in both varieties. One classical form keeps ae in both varieties: aer-as in aerate, aerobics, aerodynamics, aerosol. In both varieties, encyclopedia and medieval are commoner than encyclopaedia and mediaeval, but where BrE pronunciation typically begins ‘meddy’, AmE pronunciation often begins ‘meedy’. There is now a tendency for e and ae to become non-exclusive variants in BrE in such words as co-eval, primeval and archeology, gynecology.
5. The instil(l) group.In such words, BrE has a single written vowel plus -l and AmE has a single written vowel plus -ll, and the exclusive variants are all disyllabic verbs stressed on the second syllable: distil(l), enrol(l), fulfil(l), instil(l). Exceptionally, extol prevails in AmE over extoll. Verbs like this but with a in the second syllable belong to this class in AmE: appall, enthrall, install. In BrE, however, the preferences vary: appal, befall, enthral, install. The verb annul has -l in both varieties.
6. The final -l(l) group.In BrE, verbs that end in a single written vowel plus -l or -ll keep them before -s (travels, fulfills), have -l before -ment (instalment, fulfilment), and have -ll before a suffix beginning with a vowel (travelling, fulfilling). In AmE, verbs that end with a single written vowel plus -l or -ll keep them before -s and -ment (fulfilment, installment); before a suffix beginning with a vowel, the verbs ending with -ll keep both letters (fulfilling), but the verbs ending with -l either have -ll as in BrE (compelling, cavilling) or more usually follow the general rules for doubling final consonants (compelling, caviling). Sometimes the result is the same for both varieties: compel, compels, compelled. Sometimes it is different: travel, travels, travelled, traveller shared by both, but AmE generally travels, traveled, traveler. Parallel does not usually double its final -l in either variety.
7. The -ize and -ise group.Some verbs can only have -ize: capsize, seize. In some, only -ise is possible: advise, surprise. In many, both -ise and -ize are possible, as in civilise/civilize, organise/organize, and the -s- or -z- is preserved in derivatives: civilisation/civilization. For such verbs, AmE has systemic, exclusive -ize, and BrE has both -ise and -ize. In AusE, -ise is preferred. British publishers generally have their own house styles: among dictionary publishers, -ize is preferred by Cassell, Collins, Longman, Oxford, -ise by the Reader's Digest (UK). Chambers has -ise for its native-speaker dictionaries, -ize for its EFL learners' dictionary, intended for an international public. There is no infallible rule identifying the verbs that take both, but they generally form nouns in -tion. With the exception of improvise/improvisation, verbs that take only -ise do not generally have a noun in -tion: revise/revision, advise/advice. However, some verbs that allow both forms do not form nouns in -tion: apologise/ize, apology; aggrandise/ize, aggrandisement, aggrandizement.
8. The -lyse and -lyze group.In such verbs as analyse/analyze and paralyse/paralyze, BrE prefers -lyse and AmE -lyze. The variants are systemic and have been mutually exclusive, but recently analyze has begun to appear in BrE. The difference disappears in corresponding nouns: analysis, paralysis are international, as the /z/ of the verbs becomes /s/ in the nouns.
9. The -og(ue) group.Although in words like catalog(ue), dialog(ue), monolog(ue), pedagog(ue), prolog(ue), AmE sometimes drops -ue, only catalog is a widely used AmE variant. Thus, such spellings are systemic, non-exclusive variants in AmE. Analog(ue) is a special case: the spelling analog prevails in contrast with digital when referring to such things as computers, but that is true not only in AmE but also in BrE, where AmE spellings are generally used in the register of computing.
1. Where differences exist, AmE spellings tend to be shorter than BrE spellings: catalog, color; AmE jewelry, jeweler, BrE jewellery, jeweller; AmE councilor, counselor, BrE councillor, counsellor. Exceptions include: AmE instill and installment, BrE instil and instalment; AmE skillful and thralldom, BrE skilful and thraldom.
2. In general terms, a spelling used in Britain is more likely to be acceptable in America than is an American spelling in Britain. BrE seems sometimes to use spelling to distinguish items with the same pronunciation: tyre and tire, cheque and check, the kerb in a street and curb restrain/restraint. AmE seems to do this rarely: moral vice and vise the tool.
PronunciationBecause BrE and AmE spelling can be seen in printed and edited texts, comparing and contrasting them is more or less straightforward, but because of the diversity of speech forms within AmE and BrE, there is no analogous basis for comparing BrE and AmE pronunciation. What follows is a comparison of two major features in the pronunciations shown in British dictionaries, typically based on the accent called RECEIVED PRONUNCIATION or RP, with those in American dictionaries, typically clustering round a set of pronunciations often called GENERAL AMERICAN or GA.
1. The treatment of R.GA is RHOTIC and RP non-rhotic: that is, in GA, /r/ is pronounced in all positions in words like rare, rarer, but in RP it is not pronounced unless a vowel follows. In RP, therefore, /r/ does not occur finally in rare and rarer unless followed by a word beginning with a vowel: a rare article, a rarer article. Generally, /r/ is a retroflex consonant in GA and an alveolar consonant in RP: see R-SOUNDS.
2. The treatment of A.In about 150 words where the sound represented by the letter a precedes a fricative (such as /s, f, ɵ/) or a nasal (such as /n, m/) followed by another consonant, GA has /a/ and RP /ɑ/, as in: after, can't, dance, fast, half, pass, past. Other cases of /a/ versus /ɑ/ include aunt, example, laugh, draught, sample, and the second a of banana. The RP pronunciation is widely known as the ‘broad a’, and is considered ‘posh’ in Britain and ‘tony’ or affected in America. It is in fact a phonological bone of contention throughout the English-speaking world. In RP, in the pronunciation of the broad a, there are many traps for the unwary: grant, slant have the broad a, but cant, grand, hand, pant do not. Words such as translate and telegraph may or may not have it, and telegraphic does not.
GrammarA discussion of grammatical differences is closer to a discussion of spelling than of pronunciation, because it can be based on textual evidence. The following are significant contrasts:
1. Shall/will.Though shall is even less common in AmE than in BrE, the only significant differences concern two of the least common BrE uses: second-person questions and the contraction shan't, as in Shall you be at the embassy reception?—No, I'm afraid I shan't. Both are virtually unknown in AmE. As for will, two of its BrE uses are much less likely in AmE: inference will, roughly equivalent to must (That will be the postman at the door); stressed will indicating a disagreeable habit or practice (He WILL keep telling us about his operation!).
2. Should/would.In polite first-person statements (We should be happy to comply with your request), should is rarer in AmE than in BrE, particularly in advice-giving formulas (I should dress warmly if I were you). Should is also rarer in AmE in its putative use: I demand that they should leave; It is astonishing that they should have left without telling me. Would is primarily BrE in uses that parallel will above: That would have been the postman at the door; He WOULD keep telling us about his operation! However, it seems to be primarily AmE as an initial equivalent of used to: When I was young, I would get up early, though as a subsequent substitute for used to it is shared: I used to get up early and before breakfast I would go jogging.
3. Can/may.Both varieties use can freely for permission as well as ability, a usage formerly discouraged on both sides of the Atlantic: You can see him now (You are permitted to see him). In a negative inferential sentence like If you got wet you can't have taken your umbrella, can't is more likely in BrE than AmE, which allows mustn't (see following).
4. Must/have (got) to.An affirmative inferential sentence like This has to be/This has got to be the best novel this year is more likely to be AmE than BrE, though it is becoming an alternative in BrE to the shared This must be the best novel this year. A negative inferential sentence like If you got wet you mustn't have taken your umbrella is AmE rather than standard BrE, which uses can't (see *preceding).
5. Have (got).There have been differences between BrE and AmE in the use of have, but in the last decade they have become largely of historical interest only. The major surviving difference is the past form had got: She left because she'd got a lot to do/she'd got to do a lot is a largely BrE alternative to the shared She left because she had a lot to do/she had to do a lot.
6. Let's.The negative form let's not (argue) is shared, coexisting with the chiefly BrE variant don't let's (argue) and the AmE variant let's don't (argue), often reproved as non-standard.
7. Subjunctive forms.After words like demand, several constructions are possible: I demanded that he should (not) leave (more BrE than AmE), I demanded that he (not) leave (somewhat more AmE than BrE, especially with not), I demanded that he left/didn't leave (far more BrE than AmE).
8. Perfective forms.With yet and already, such perfective sentences as Have you eaten yet? and They've already left are shared usages. Such alternatives as Did you eat yet? and They left already are virtually exclusive to AmE, but may be regarded as non-standard.
9. Tag forms.Such sentences as They're here, aren't they? combine positive and negative verb forms and are shared. Such sentences as So they're/They're here, are they? combine positive with positive and are somewhat more BrE than AmE. Such sentences as So they/They didn't do it, didn't they? combine negative with negative, are virtually exclusive to BrE, and are not used freely even by all BrE speakers. Tags used otherwise than to elicit or confirm information tend to be more BrE than AmE, in particular peremptory and aggressive tags such as You'll just have to wait and see, won't you? and I don't know the answer, do I?
10. Give.The form Give me it is shared, while Give it me is BrE.
11. Provide.The form That provided us with an excuse is shared, while That provided us an excuse is AmE.
12. Enough.The form They're rich enough to retire is shared, while They're rich enough that they can retire is chiefly AmE.
13. Agree, approximate, protest.The forms They agreed to the plan and They agreed on the plan are shared, while They agreed the plan is BrE. That approximates to the truth is chiefly BrE, while That approximates the truth is AmE. They protested their innocence and They protested against/at the verdict are shared; They protested the verdict is AmE.
14. Time expressions.The form Monday to Friday inclusive is shared, while the synonymous Monday through Friday is AmE. Monday through to Friday is BrE, and may be ambiguous as to whether Friday itself is included. The forms a week from today and a week from Friday are shared, while a week today, a week on Friday, Friday week are BrE. The form half past six is shared, and coexists with the informal BrE half six. The use of past in time expressions (10 past 6, (a) quarter past 6) is shared; the corresponding use of after (10 after 6, (a) quarter after 6) is chiefly AmE. The form ten (minutes) to six is shared, while ten (minutes) of six is AmE.
15. Go, come.The forms Go and see/Come and see what you have done are shared, while Go see/Come see what you have done are AmE.
16. One.The form If one does one's best, one will succeed is shared and tends to be formal in both varieties, while If one does his best, he will succeed is AmE (and under attack by feminists and others as sexist usage).
17. Group nouns.Such a collective usage as The government is divided is shared, while The government are divided, emphasizing the members of the group, is chiefly BrE.
18. Collocations.There are many differences of idiom. The collocations go to church/school/college and be at church/school/college are shared, but go to university/be at university and go to hospital/be in hospital are BrE, AmE requiring the as in go to the university. Forms like in a jubilant mood are shared, but in jubilant mood is BrE. The expressions on offer and in future are BrE, the former the equivalent of the shared being offered, the latter of the shared from now on/from then on. The form in the future is shared. The form do a deal is BrE and make a deal is AmE. Take a decision is chiefly BrE, though make a decision is shared. Seems/Looks like a good deal is shared, but Seems/Looks a good deal is chiefly BrE. Members of is shared; membership of is BrE; membership in is AmE.
Vocabulary and idiomsAs with differences in spelling, lexical differences can be divided into the exclusive (such as BrE windscreen, AmE windshield), and the non-exclusive. The non-exclusive differences subdivide into those in which the shared variant coexists with an exclusive usage (such as shared editorial, BrE leader; shared autumn, AmE fall), and those in which a shared variant coexists with both a BrE variant and an AmE variant (shared socket, BrE power point, AmE outlet). Systemic differences in vocabulary are due to two factors: source and subject. AmE and BrE draw on different sources for certain words, especially in informal styles, AmE drawing for example on Spanish because of its associations with Latin America, BrE drawing for example on Hindustani because of its long connection with India (see COCKNEY). They have also developed differences in some subjects more than others. In areas of technology that developed before the European settlement of America, such as sailing, differences are small; in those developed in the 19c, such as rail and automotive transport, they are much greater, but in 20c technology, such as aviation, they are few. In the vocabulary of computing, AmE spellings are used in BrE, such as program, disk, while BrE programming is used in AmE. See AMERICANISM, BRITICISM.
AmE and BrE sometimes have slightly different idioms, such as: BrE a home from home, leave well alone, a storm in a teacup, blow one's own trumpet, sweep under the carpet, AmE home away from home, leave well enough alone, a tempest in a teacup/teapot, blow one's own horn, sweep under the rug. The use of preposition is often different: for example, Americans live on a street while Britons live in a street; they cater to people where Britons cater for them; they do something on the weekend where Britons do it at the weekend; are of two minds about something while Britons are in two minds; have a new lease on life where Britons have a new lease of life. American students are in a course and British students on a course. Americans can leave Monday while Britons must leave on Monday. See letter entries E, L, O, R, Z.
Measurement, English System of
Measurement, English System of
Early measurements of length were based upon parts of the human body, which for a long time were accurate enough for daily calculations. It is still common for us to use hand, finger, and arm movements to accompany statements regarding size or dimension.
The first known standard length was used around 3000 b.c.e. in Egypt. The Egyptians created the cubit, which was the distance between the elbow and the tip of the extended fingers. The Egyptians overcame the variation from one person to another by making a standard cubit equal to what is now 20.62 inches.
The Greeks adopted the Egyptian cubit as the basis of their system, but also had their own measure of length, the fathom, which was the distance from fingertip to fingertip with arms outstretched. The Greek historian Herodotus (484 b.c.e.–424 b.c.e.) stated that the fathom was equivalent to four cubits (or six feet). From Plutarch (46 c.e.–120 c.e.) it is known that the Parthenon of Pericles in Athens had a platform length of 100 feet. When measured with modern units, it is found that the Greek foot was 12.14 of today's inches. The foot was passed to the Romans who subdivided it into 12 equal parts that they called the uniciae.
Medieval Europe was greatly influenced by the Roman system of units. Nevertheless, regional variations over the centuries resulted in a number of standard lengths. In the ninth century, Charlemagne tried to impose a uniform unit of length throughout Europe but failed due to people's reluctance to accept new units.
Charlemagne's efforts, however, did not go unrewarded and over the next few centuries the great trade fairs of Europe always had a Keeper of the Fair whose unit of length was compulsory for all commercial transactions within the fair grounds. The most prestigious unit of length was the Ell of Champagne, which was 2 feet 6 inches long, and was used in most of Europe as the standard measure for cloth, the most valuable of all trade goods at that time.
An early attempt to standardize units in England resulted in a return to the royal standard, with the ell being equal in length to King Henry I's (1068–1135) own right arm. Present-day knowledge of the use of the royal arm is from the writings of William of Malmesbury (1095–1143), who has proven to be a reliable source for historical data. This ell was a larger measure than that used in cloth measuring, and eventually it became the yard.
By tradition, the yard of Henry I was the distance from the royal nose to the outstretched fingertips of the royal's right hand. The length was also chosen to ensure that 5½ yards equaled a rod, the fundamental unit for measuring land. Because land was the greatest measure of wealth in the Middle Ages, this correspondence was of particular importance. The rod was the Saxon measure for land and the Norman conquerors wanted to ensure that the land holdings of Saxon allies and new Norman landlords were precisely understood.
The Saxon word aecer, from which the word "acre" is derived, meant a field, or sown land. An aecer was 4 rods wide and 40 rods long, with the latter measurement being known as a furlong. The aecer represented about 5 hours of plowing by a team of oxen, the maximum the team could be expected to do in a day.
Hints of Change. By the time of the Magna Carta in 1215, the standards in England varied so widely that the thirty-fifth clause of the charter specified measurements for the unit of length as well as the gallon and the pound.
The next major review of the English units of measure occurred under the Tudor dynasty. In 1491 Parliament ordered the construction of new standards for length, weight, and capacity. These new Exchequer standards were stored in the Treasury, and in 1495, copies of these standards were supplied to forty-three shire towns in England. There was no change from the earlier yard and a later recalibration of measures in the reign of Elizabeth I also left the yard unchanged from the traditional length.
To Change or Not to Change
Between the reign of Queen Elizabeth I starting in the late sixteenth century and 1824 there were many proposals to refine or change the system of measurement. Many were based on the scientific knowledge generated by the Renaissance and the Enlightenment. However, they all failed to gain acceptance because they lacked the support of the English Parliament. The arguments for rejecting any proposed change was the one still used in the twenty-first century: namely, that it would a very expensive change for merchants and manufacturers. These arguments were also used against moving toward a metric system that was tainted by its association with Napoleon's imposition of this system on Europe.
In the United States, Thomas Jefferson (1742–1826) reported to Congress in 1791 on weights and measures to be used in the new republic. He assumed that traditional measures would continue as they were well understood by the public, but he did try to recommend a decimal system of his own devising. In 1821 John Quincy Adams (1767–1848) reported to Congress that a uniform set of weights and measures was urgently required, and suggested that the metric system be adopted. This recommendation was not accepted.
In England, the Imperial Weights and Measures Act of 1824 repealed all previous legislation with respect to weights and measures. However, this new Imperial System of Measurement did not create a complete break with the past. The standard yard was defined as the distance between the centers of two gold studs on a brass rod that was in the custody of the Clerk of the House of Commons. The temperature of the rod when a length was to be verified was to be 62° F. All measures of length were derived from this standard yard.
In 1834, the British Imperial Yard was destroyed by fire when the Houses of Parliament burned. A new Imperial Standard was designed and extensively tested to ensure that it matched perfectly the Elizabethan yard. The imperial standard yard still exists and is a solid gunmetal bar 38 inches long. The material used is an alloy of copper, tin, and zinc in the ratio 16:2.5:1. This alloy was selected because it gave a stiff bar and also had a very small change in length when the temperature varied. Near each end of the bar is a hole ⅜ inches in diameter with the two centers 36 inches apart. These holes were sunk halfway through the bar and have gold studs in them. On each of these gold studs are two lines parallel to the length of the bar and three other lines, 0.01 inch apart, at right angles to these parallels. The gap between the central line on each end is defined as the imperial standard yard. The entire bar rests on eight bronze rollers to avoid flexing. Copies of this new standard were presented to the United States, where the Office of Weights and Measures subsequently adopted it as a new standard, replacing all previous standards.
The Move to Metrics
In 1864 the use of metric units became permissible in England and in 1866 the metric system was made legal throughout the United States. Nine years later the United States went a step further and signed the Treaty of the Meter that established an international Bureau of Weights and Measures. In 1890 the signers of the Treaty each received exact copies of the International Prototype Meter and Kilogram. Three years later the Secretary of the Treasury issued the Mendenhall Order, which stated that the International Prototype Meter and Kilogram would be regarded as the fundamental standards from which all other measures in the United States would be derived. The yard was fixed at 0.91440183 meters and the pound at 0.4535924277 kilograms.
During the next 50 years, comparisons were made between the English and American standards. Though they were supposed to be identical, the English standard was found to be minutely smaller than that of the United States. The slight difference did not create problems in commercial transactions between the countries. During World War II, however, the need for precise aircraft parts showed that the discrepancy made a difference in other areas.
In 1959, Australia, Canada, New Zealand, South Africa, the United Kingdom, and the United States adopted a common standard for the inch:2.54 centimeters. However, the U.S. Coast and Geodetic Survey retained their established relationship of an inch equaling 2.540005 centimeters, which avoided extensive revisions to their charts and measurement records. The resulting foot is known as the U.S. Survey Foot. Since 1959, Australia, Canada, New Zealand, South Africa, and the United Kingdom have dropped the English yard as a legal unit of length and replaced it with the meter.
see also Measurement, Metric System; Mile, Nautical and Statute.
Conner, R. D. The Weights and Measures of England. London: Her Majesty's Stationery Office, 1987.
Donovan, F. Prepare Now for a Metric Future. New York: Weybright and Talley, 1970.
Zupko, R. E. Revolution in Measurement: Western European Weights and Measures Since the Age of Science. Philadelphia: The American Philosophical Society, 1990.
Charlemagne (742–814), emperor of the West, wanted to standardize measurements to improve administrative procedures in his vast empire, which stretched from the Atlantic ocean to what are now the borders of Poland (east) and of the Czech Republic.
English units of measurement
English units of measurement, principal system of weights and measures used in a few nations, the only major industrial one being the United States. It actually consists of two related systems—the U.S. Customary System of units, used in the United States and dependencies, and the British Imperial System. The names of the units and the relationships between them are generally the same in both systems, but the sizes of the units differ, sometimes considerably.
Customary Units of Weights and Measures
Units of Weight
The pound (lb) is the basic unit of weight (which is proportional to mass). Within the English units of measurement there are three different systems of weights. In the avoirdupois system, the most widely used of the three, the pound is divided into 16 ounces (oz) and the ounce into 16 drams. The ton, used to measure large masses, is equal to 2,000 lb (short ton) or 2,240 lb (long ton). In Great Britain the stone, equal to 14 lb, is also used. The troy system (named for Troyes, France, where it is said to have originated) is used only for precious metals. The troy pound is divided into 12 ounces and the troy ounce into 20 pennyweights or 480 grains; the troy pound is thus 5,760 grains. The grain is also a unit in the avoirdupois system, 1 avoirdupois pound being 7,000 grains, so that the troy pound is 5,760/7,000 of an avoirdupois pound. Apothecaries' weights are based on troy weights; in addition to the pound, ounce, and grain, which are equal to the troy units of the same name, other units are the dram (1/8 oz) and the scruple (1/24 oz or 1/3 dram).
Units of Length and Area
The basic unit of length is the yard (yd); fractions of the yard are the inch (1/36 yd) and the foot (1/3 yd), and commonly used multiples are the rod (51/2 yd), the furlong (220 yd), and the mile (1,760 yd). The acre, equal to 4,840 square yards or 160 square rods, is used for measuring land area.
Units of Liquid Measure
For liquid measure, or liquid capacity, the basic unit is the gallon, which is divided into 4 quarts, 8 pints, or 32 gills. The U.S. gallon, or wine gallon, is 231 cubic inches (cu in.); the British imperial gallon is the volume of 10 lb of pure water at 62°F and is equal to 277.42 cu in. The British units of liquid capacity are thus about 20% larger than the corresponding American units. The U.S. fluid ounce is 1/16 of a U.S. pint; the British unit of the same name is 1/20 of an imperial pint and is thus slightly smaller than the U.S. fluid ounce.
Units of Dry Measure
For dry measure, or dry capacity, the basic unit is the bushel, which is divided into 4 pecks, 32 dry quarts, or 64 dry pints. The U.S. bushel, or Winchester bushel, is 2,150.42 cu in. and is about 3% smaller than the British imperial bushel of 2,219.36 cu in., with a similar difference existing between U.S. and British subdivisions. The barrel is a unit for measuring the capacity of larger quantities and has various legal definitions depending on the quantity being measured, the most common value being 105 dry quarts.
Differences between American and British Systems
Many American units of weights and measures are based on units in use in Great Britain before 1824, when the British Imperial System was established. Since the Mendenhall Order of 1893, the U.S. yard and pound and all other units derived from them have been defined in terms of the metric units of length and mass, the meter and the kilogram; thus, there is no longer any direct relationship between American units and British units of the same name. In 1959 an international agreement was reached among English-speaking nations to use the same metric equivalents for the yard and pound for purposes of science and technology; these values are 1 yd=0.9144 meter (m) and 1 lb=0.45359237 kilogram (kg). In the United States, the older definition of the yard as 3,600/3,937 m is still used for surveying, the corresponding foot (1,200/3,937 m) being known as the survey foot.
The English units of measurement have many drawbacks: the complexity of converting from one unit to another, the differences between American and British units, the use of the same name for different units (e.g., ounce for both weight and liquid capacity, quart and pint for both liquid and dry capacity), and the existence of three different systems of weights (avoirdupois, troy, and apothecaries'). Because of these disadvantages and because of the wide use of the much simpler metric system in most other parts of the world, there have been proposals to do away with the U.S. Customary System and replace it with the metric system.
See L. J. Chisholm, Units of Weights and Measure: International and U.S. Customary (U.S. National Bureau of Standards, 1967).