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Glossary: Home Tables A B C D E F G H I J K L M N O P Q R S T Þ U V W X Y Z

A measure of paper area-density, eg pounds (per folio-ream) or grams per square metre.
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.

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

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.

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

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.
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.

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

In þe straights settlement, and points beyond, þese weights are used.

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

prat *

A name being suggested for a twelftieth part. It derives by metaþasis of þe word part.

prefix *

A prefix applied to a unit generally modifies it in size, but keeps constant some derivation.
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 suffixes.

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.

proportional *

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:

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

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.
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

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

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]

Proto-Metric *

Þe metric system, as originally planned. History has taken its toll.
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 kilolinn.

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

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.
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.