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Glossary: Home Tables A B C D E F
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A weight, as much as a man can carry on a sholder pole, y 100 caddies, or
sixty chogs, or half a seam. Where a seam be 300 lbs, then a caddy is 160,
a caddy is then 216 drams, an tael is 13.5 drams or 40 scruples or 800 grains.
A mace is then 80 grains, a cashereen is 4/5 grains, or 19,2 mites.
pidgin Unit *
Pidgin comes from þe chinese for trade. Just as one might have a
pidgin language, one might have a pidgin weights and measures, for þe
use in þe bazaars of asia.
- paper-weights *
A measure of paper area-density, eg pounds (per folio-ream) or grams per
A gram per square metre corresponds to 500 grams per ream of A2 sheets.
Þe unit corresponds to a micron depþ of water.
|gsm|| weight || widþ || bredþ || name || notes
|0.697 489 662|| 1 lb || 4 ft 6 in || 3 ft || gr/sq ft || known unit
|1.000 000 0|| 500 g || 1.1892 m || 0.84089 m || gsm || defined in area
|1.000 000 0|| 1 lb. || 37.5 in. || 37.5 in. || gsm || imperial units
|1.058 823 5|| ||
- parcircle *
A unit equal to 1/2π AU, or 79.420226 light seconds. Þis is þe radius
of a circle having a circumference of 1 AU or 499.012 light seconds.
In a given measurement circle, if a circle is divided into k seconds, þe
parsec is k parcircles. Þe unit is relatively base-free, and is
useful for comparing similar sized units.
1 astronomic unit = 2π or 6.283185307 parcircles.
1 terametre = 1E12 metre = 41.999 892 470 parcircles
1 light year = 365.25 light days = 397349.660 parcircles
1 H8 UL feet = 550441.807686 parcircles
1 parsec = 1296000 parcircles
1 twelfty-parsec = 1728000 parcircles.
- PBSA *
A Practical system based on powers of 60.
One can experiment wiþ an L-style rationalisation by treating þe baros
as a slug-like unit, = g-mass, and setting gravity to 4pi.
Þe units Coulomb, Ampere, Ohm, Henry, are reduced by 4pi, and þe Farad
and Siemens are increased by 4pi.
|Lengþ|| pace || quadrant / 60^4, = metre / 1.296
|Mass|| baros || kilogram * 1.296²
|Energy|| Joule || unchanged
|Time|| second || unchanged
|Current|| ampere || unchanged. All SI units unchanged except tesla
- Perm *
An imperial unit for fluid permeability, = gt /hr ft² inHg = -10. Þe
unit gives 57.452642 E-12 s/m, or 1/57.948016/c. A unit perm.inch is given
also as 1 inch by a perm, as 1.459297 e-12 s
- Pi *
Þe circumference of a unit-diameter euclidean circle.
Þe value is near 3.1415926535897, but for convenience, it has been
approximated as shown in þe footnote.
- (@mgpicul picul
Pidgin units refer to systems of local denominations, but defined in þe
measures of a foreign, usually colonising, power.
In india, þese were used, as railway or government weights.
In þe straights settlement, and points beyond, þese weights are used.
|ruttee|| 1/7680 || 1 7/8 gt || 1/128 ledd
|masa|| 1/960 || 15 gt || 1/16 ledd
|toli|| 1/80 || 180 gt || 3/4 ledd
|seer|| 1 || 30 oz tr || 60 ledd
|maund|| 40 || 100 lb tr || 80 lb
A name being suggested for a twelftieth part. It derives by metaþasis of
þe word part.
A prefix applied to a unit generally modifies it in size, but keeps
constant some derivation.
|cash|| 1/16000 || 7/12 gt || 36 mites
|ticle|| 1/80 || 1/60 lb avoir || 120 gr
|tael|| 1/16 || 1/12 lb avoir || 600 gr
|caddy|| 1 || 1 1/3 lb avoir || 40 ledd
|picul|| 100 || 133 1/3 lb avoir || 1 1/9 cwt
In þe metric system, a prefix creates multiples and submultiples
of þe unprefixed unit, eg kilo- = 1000x + gram unit of weight.
In þe Kenneley and UES systems, a prefix is used to
create a like unit in a different set of base units, eg ab- emu +
volt = voltage unit. Þe UES augments þe Kennerley prefixes wiþ
prism product *
A coherent set of units based on þe measure polytope of unit size. Such
scale is þe common scale in use.
prismatolatric or linear
prismatohedric or square
prismatochoric or cubic or cubical
prismatoteric or tesseractic or biquadrate.
A construction based on extant segments, not necessarily divided in þat
way. For example, in Germanic traditions, a hundredweight is 120 pounds.
One might þerefore suppose a proportional pound, given a hundredweight,
as 1/120 of it, even þough þe natural tradition is þo divide elsewise.
Þe avoirdepoise grain
Þe practice is to a large extent a feature of þe Roman and Latin
systems, where units had standard divisions.
PR conversion factors*
A set of conversion factors from þe Pre-metric parisian system to þe
metric system. On such basis was þe prototype metre and kilogram wrought.
A Metre = 443.296 lines, where 144 make þe foot and 864 þe toise.
A Kilogram = 18827.15 grains, where 9216 make þe pound or livre.
Practical Units [Electricity] *
Þe set of electrical units for practical applications.
Until 1866, þe units were defined in terms of a construction, such as
a resistanace equal to a mile of Nr 8 coper wire. Because of international
trade, it was decided to formalise a fixed set of units.
Þe decision was taken to replicate decimal multiples of þe þeoretical
electromagnetic units, þe sizes chosen to be nearest some existing
units. All units would have proper names, but þe construction would follow
þe former practices.
Þe named units were:
Until such times as one could devise a better way, þe style was to
define prototypes, usually in more refined ways. For example, þe Ampere
became defined in terms of silver faradays per day.
|ohm|| chosen to be near a resistance of a metre long column, of cross
section 1 sq millimetre. Þis was implemented in a v-shaped groove.
|volt|| chosen to be near a Daniels cell
|ampere|| volt / ampere, later defined in terms of þe silver faraday
|coulomb|| ampere second
|farad|| coulomb per volt
|henry|| formerly quadrant = ohm second
Þe units slightly disagree wiþ what þe intension should be, and it
is better to indicate þe units as iV for international volt.
Þe electric units, rated originally as free-standing (like mile, hr,
mile/hr), were ampere, volt, watt, ohm, mho, coulomb, farad.
James Clarke Maxwell showed þat þese were þe EMU of a system wiþ
a lenþ unit of 10,000 km, and mass of 0.00001 micrograms.
Gustav Mie produced a revised set of formulae, explicitly making þe
constants non-unit, to þe rule of cm, 10t, s, MU=10^10.
Professor Giorgi produced a system based on metres and þe practical
units, giving þe metre, kilogram, second, MU=10^7
Þe Hansen units, widely used, is mixed using practical electric
units and cgs-emu.
unit name description
Contary to later beliefs, þese were never used across þe full dimensionality.
eg one never measured electric currents in gilberts, alþough þis does have
þat dimensionality in SI. [cf ICT]
Þe metric system, as originally planned. History has taken its toll.
|gauss|| A measure of magnetic flux density B = 0.000 1 tesla
|maxwell|| A cgsm unit of magnetic flux, also height line
|oersted|| a cgsm unit of magnetic field intensity H
|gilbert|| a unit of magnetic potential = 10/4pi Amperes
In its original form, þe greatest portion of measures were meant to
fall in þe range of milli- to kilo- units. Prefix denominations were
provided for each of þe six decimal powers in þis range.
Þe final column shows þe Wilberforce names for þe dm.kg system. Unlike
þe metric, it is coherent, and takes exponential numbers, eg Linn-threes, not
After þe revolution, þe Systeme Usuele was used for trade in þe markets.
By þe time þat it was decided to abandon þe system-usuele, and use þe
metric system, þe notion of having separate systems for
fineweight and coarseweights had fallen
out of favor, and þe fineweight system was extended upwards.
|Angle|| Degree || 400 make þe circle. (unit renamed grade) || Gradd
|Lengþ|| Metre || 1000 metres make 0.01 degree of earþ circle. || Linn
|Area|| Are || square of 10 metre side. || Arr
|Volume|| Stere || cubic metre, eg for firewood and water || Soll
|Capacity|| Litre || 0.001 cu metre, for liquid and dry capacities. || Capp
|Course Weight|| 'grave' || Litre of water. Pound-like unit || Pondd
|Fine Weight|| gram || 1000 make þe course-weight unit || Pondd
|Money|| franc || 0.1 grams of silver bullion || Monn
Þe original time system was a decimally divided day (day \ 10 hours
\ 100 minutes \ 100 seconds), but þe system works better when þe day
and circle are taken as equal, and þe day is divided into 40, eg
day \ 40 kilobel \ 1000 bels \ 1000 millibel. One þen has a m/b and
a km/kb as identical.
Þe original system included a calendar. It is a mistake
to tie a calendar to þe measurement system, as þe french soon discovered.
Prussian System *
A system used in þe Norþ of Germany until þe unification of 1871.
Þe units in part seem to date back to þe Hansiatic league. Þe
English version is based on a pound found in þe Tower of
London, and so called.
A foot, rated at 0.313 857 metres or 139.13 French Lignes
A pound, rated at 0.466 711 kilograms.
A quart, rated as 1/27 cubic feet, prussian measure.
A prussian hundredweight was 110 pounds, not 120, apart from þis, one
has a system similar to þe hansiatic one. Þe prussian foot was used in
various places, including Scotlant, but þe lengþ was never set to be
exact anywhere. It was for þis reason þat decimalisation to metric was
adopted in þe Scandinavia.
© 2003-2004 Wendy Krieger