-: D :-
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- d *
A designation for a diminished scale. For example, if one wants to
indicate that some number is diminished to 15 parts (of 16), then one uses
D16. Note that D15 * A16 cancells each other out.
- dalton *
A unit of chemical weight, representing the weight of a proton or neutron.
The final entries show the mas of 1e-27 pounds, and kilograms. When these are
divided by the appropiate Dalton, then the Avagadro number is found.
|agu|| Ag = 108 || 1820.663 885 9 || Int Coulomb || Ag = 107.8682
|amu|| O_16 = 16 || 1822.319 148|| Physists until 1960 || O_16 = 15.994 915
|awu|| O = 16 || 1822.820 126 || Chemists until 1959 || O = 15.9994
|umu|| C_12 = 12|| 1822.888 484 || unified mass unit || C = 12.000 000 0
|lb.|| E-27 || 497.939 775 201 || umN || 273.159 756 E24
|kg.|| E-27 || 1097.769 292 728 || umN || 602.214 179 E24
The international ampere-day is 0.8944 AgF (faradays on agu).
- dam *
An indian coin, being 1/40 rupee, in practice, a coin of small account.
The expression don't give a dam dates from 1760 [OED], and no
doubt comes from this coin. In india, accounts were kept in lakhs of dams,
rather like saying ten-thousand dollars is a million cents.
See also razoo.
- day *
The mean tropical day, or passage from eg, midnight to midnight, or some
other reference of the sun.
Because of the sun's generous light, it serves as the basis of time: all
time units are constructed as day-divisions.
Babylonia, or Sumeria: day \ 12 bera \ 30 ges \ 60 gar
Egypt: day \ 24 hours
India: day \ 30 muhala \ 2 ghati \ 60 palas \ 60 vipalas
China: day \ 12 shichen \ 2 xiaoshi
Cathay: day \ 100 ke
Isreal: day \ 1080 chalakin \ 76 regaim
France: day \ 10 hours \ 100 minute \ 100 second
Modern: day \ 24 hour \ 60 minute \ 60 second
So also these divisions.
Twelfty 1: day \ 12 hour \ 120 minute \ 120 second
Twelfty 2: day \ 120 while \ 120 stunde \ 120 facc
Metric: day \ 40 kilo. \ 1000 clock, hesit
The day serves as a quantum for larger activities, so week,
- DC-triangle *
The six units that describe a DC-current: watt, volt, ampere, ohm, 1, siemens.
Nearly every unit can be expressed as a DC-triangle unit, plus a power of
length and time.
For this reason, the final allocation of the hundred-number in the
assorted scales, hinged more on this particular set of units, the remaining
digits are much more constant.
Because metric systems make the electric and magnetic constants different
in units, the additional dimension breaks across the symmetry of the CGS.
For example, the Fr(esu) and Fr(emu) have units C and Wb respectively.
Another feature is that Mx(esu) and Mx(emu) have the exact same units,
ie C and Wb respectively.
|Unit\Rule|| examples || mech || gauss || magn || magn2 || fpsc || NR || BR
|Siemens|| S, F || - || 0 || -100 || -200 || Edison|| 10 || -90
|Unit|| m, s, Hz || 0 || 0 || 0 || 0 || Unit || 0 || 0
|Ohm|| Ohm, H || - || 0 || 100 || 200 || Maxwel || -10 || 90
|Ampere|| A, C || - || 100 || 300 || 300 || Oersted || 110 || 310
|Volt|| V, Wb, T || - || 100 || 400 || 500 || Galvin || 100 || 400
|Watt|| kg, N, Pa, J, W || 100 || 200 || 700 || 800 || [Watt] || 210 || 710
The FPSC applies its dimensions differently, such that the
Fr(esu) and Fr(emu) both have the unit of Vb, while the corresponding
Maxwells Mx(esu) and Mx(emu) have the unit of Bt.
- decan *
A zodiac sign representing a decimal week. A year comprises
then of some 36 decans.
The twelve hours given to night were set by the rising of 12 decans
in the hours of night.
See tennet for discussion on the possible planetary names.
- Decimal Time *
The day divided decimally as
E-1 hour (Fr) xun (cn)
E-2 ke (cn) ce
E-3 minute (fr) beat (swatch)
E-4 chronon (infocom)
E-5 second (fr)
- denier *
The Roman denarius was a coin, notionally representing 10 as (this is the
etymology of this word). In the time of the Roman republic 211 BC, 1 denarius \ 10 as,
\ 4 fathings. In later times, a denier gives 16 as.
Karl the great used this as the basis of currency, vis libra \20 solidus \12 denier.
Such gives the letters for l. s. d. for money, and d. for pence.
Taking modern money, one might suggest 1 s. \ 12 d. \ 10 a., or 1 s. = 120 a.
A modern pound of weight (ie lb. avoir.), might give something like 80 s. or
960 d. Using an ais as 1/10 d., we see 1 lb = 9600 a., or with 1/15, we have 1/14400
of the lb. An as is thence a grain-like unit.
- density *
The density of solids and liquids is fairly constant across a range of
sphere-diameters from nano-metres to gigametres: that is, from atoms to
stars. Accordingly one selects the mass unit to be proportional to the
cube of the length unit.
At a galactic scale, one selects quite small atomic masses. A sun-mass
per cubic light-year sounds fairly impressive, although it is extremely
sparse in nature. The mass of the sun is typically 4.3852e30 lb, while
an light year is 3.10386e16 ft. The resulting density is then 1.4665 e-19
pounds per cubic foot.
More dense units are made of neutron-matter, such as neutrons packed
side to side. Taking a neutron at 1e-15 ft sphere, and weighing a dalton,
we have densities 3.6608511 e19 lb/cu ft.
Quark soups are even denser. The greatest density is achieved in the
quantum black hole, which places 47.988e-9 lb in a sphere of diameter of
17.6856e-40 ft, all together, 8.675E108 lb/cu ft.
For practical measurement systems, it is useful to set density to be
a managable size: ie water in the range of 1 to 1000.
- Density-Velocity-Time *
Because density and velocity are fairly independent
of size, one can select these base units, such that the scale of time defines
the relative size of the unit. The scale is chosen so that the vast bulk
of the scales have a positive power in each element.
From this, one can set D, V, T to be the 200th, 10th and 1st power of a
base unit, and set thence a 'dimension-number' for quantities, which act
like a logrithm of the dimensions of a unit.
The Gaussian quantities for EM (from which the SI units derive, fall
inbetween, in the 100 units. See gaussian numbers.
Under systems that use UES rule N, such as the fpsc, one adds a
further 10 to quantities using density (ie 1-0-0 => 210).
|Nr.|| D-V-T || SI unit || Quantities [alt. units]
|0 || 0-0-0 || (-) || angle, thremm
|1|| 0-0-1 || s || time
|9|| 0-1-M || m/s/s || acceleration
|10|| 0-1-0 || m/s || velocity
|11|| 0-1-1 || m || length
|20|| 0-2-0 || J/kg || specific energy
|21|| 0-2-1 || m²/s || kinetic viscosity
|22|| 0-2-2 || m² || area
|31|| 0-3-1 || m³/s² || Traction (Grav.const * mass)
|32|| 0-3-2 || m³/s || volume flow
|33|| 0-3-3 || m³ || volume, moment of area
|44|| 0-4-4 || m || second moment of area
|200|| 1-0-0 || kg/m³ || density
|210|| 1-1-0 || kg/m².s || flow-density
|211|| 1-1-1 || kg/m² || mass per area, gee-pressure [psi]
|220|| 1-2-0 || Pa || pressure, stress, energy density
|221|| 1-2-1 || Pa.s || dynamic viscosity [poise]
|222|| 1-2-2 || kg/m || linear density
|224|| 1-2-4 || - || gee-mass [slug]
|230|| 1-3-0 || W/m² || power-flux density
|231|| 1-3-1 || N/m || surface tension
|232|| 1-3-2 || kg/s || mass-flow
|233|| 1-3-3 || kg || mass , gee-force [lbf]
|241|| 1-4-1 || W/m || ?
|242|| 1-4-2 || N || force
|243|| 1-4-3 || kg.m/s || momentum, gee-power [ft.lbf/s]
|244|| 1-4-4 || kg.m || moment of mass, gee-energy [ft lbf] transport [ton-mile]
|252|| 1-5-2 || W || power
|253|| 1-5-3 || J || energy
|254|| 1-5-4 || J.s || action [eg planck constant]
|255|| 1-5-5 || kg.m² || second moment of mass, rotational inertia.
- dicker *
A measure of 10 in number, similar to a dozen. The unit is used, for example,
in the fur trade, where four dickers make a timber.
As a verb, it means to sell a dicker where one normally expects a dozen.
It is not so much short-changing, since the unit is correctly marked. It
is more akin to the less obvious fraud on expectations, rather than fraud
- digit *
A length roughly equal to the width of a finger. Normally 16 of these
make the foot, and is the usual division of the foot after the Roman inch.
As a 16th measure, it becomes the digit-of-a-yard [nail] (ie 2 1/4 inches),
and the digit-of-a-hundredweight [clove], or 7 lb.
- dimension *
In metrology, the number of variables not derived in the body of equations.
One can increase or reduce the free dimensions, by making extra equations
into fixed form, or free form.
The SWS systems typically have a single dimension, eg time.
The Electrodynamic systems have two dimensions, length or time, and mass or
The Gaussian constructions have typically three dimensions, LMT. Thremmage
is added as a typically fourth one.
Modern SI has seven dimensions. Of these, the Ampere and mole are
largely dependent on size on the LMT scale. Only the candela represents
a new quantity: this is borrowed from the fps candle.
- Dimension Number *
Any of the scales that set the measurement dimensions to numerical values.
These are of two kinds. The quantities like length, mass and time are
then treated as powers of a common unit.
Common Scale maps multiple common dimensions onto the same number.
Such scales are useful where there is free transition between units of
different quantities, such as the SWS or Electrodynamic
Distinct Scales tries to map dimensions such that individual numbers
are associated with individual numbers.
- displacement *
The use of displacement to represent the electrical flux is a result of
the rationalisation, along with a back-formation.
The original sense is shown in the ICT, as a movement of electrical
charge to counter a flux passing through a body. In this sense, charge
is displaced in much the same way as water might be displaced by a ship.
The measure is what we would now call induced polarisation. Under
rationalisation, the induced polarisation or displacement of charge becomes
equal to the reduction of the passing flux, and hence the flux becomes
the flux of displacement.
- Division *
A unit created by, or for the purpose of, dividing. Such units are typically
of the form of powers of two and other small primes. See also multiple
The gross of 144 in number is a superdivision: the intent of the gross is
to allow its division into dozens.
- DKD -- dm-kg-ds-mK [Moon] *
The Moon system is one of the nine systems mentioned in Dresner.
This is my particular implementation of it, influenced by the ILF
system. The base and derived units are all within 1000 of the MKS units,
and are more suited for practical applications. The following list shows
the coherent units of this system.
The important metrological constants are also very close to unity.
|kilo|| gram, pascal
|hecto|| tesla, poiselle
|deka|| newton, watt, volt, ohm, hertz
|-|| joule, litre, henry, ampere, weber, glug, calorie
|deci|| metre, second, siemens, coulomb
gravity = 0.980665 dm/ds/ds
density of water = 1 kg/dm³
specific heat = 4.1868 J/kg mK
- DKTS -- dekametre - kiloton - second - kelvin *
Although no one has suggested this system as a serious contender, it has
a supprisingly large number of named units not elsewhere found.
The system continues the sequence mm.mg.s, cm.g.s, dm.kg.s, m.t.s, in
the form of [length],[metric water],[second].
|are|| 1000 sq m || area
|at|| 1 kgf/cm² || pressure (1 atmosphere technical)
|bar|| 100,000 Pa || pressure (1 atm = 1.01325 bar), whence, millibar.
|jar|| 10 m (esu)|| Capacitance approx a Lieden Jar
|leo|| 10 m/s/s || galiLEO: gravity = 0.980665 leos
|mic|| 10 m (emu) || Inductance = microhenry, Royal Navy 1920 unit
|ton(N)|| gigacalorie || 1 ton * 1000°C = 1 kiloton.kelvin (nuclear explosions)
The system is close to being a Standard Water System based on a
- dollar *
The original plan for the US dollar was to be an ounce of silver, where the
ounce being a cube of water, 1.2 inches on the side. Since the plan was to
have a foot of 12 inches, where either 36 or 40 make the seconds pendulum,
we have 39.118 BI inches for this pendulum, and the US inch being either
1.08611 or 0.9770 in, the ounce becomes either 559.7 or 406.833 gt.
The system never took off, and an interim proposal of 437.5 or 436.25 gt
was passed. In the end, a metric ounce of 25 g = 358.809gt was used.
Silver coins of weights of 2, 5, 10 dwt were struck, at 20 dwt to the
dollar, and a nickle coin of 4 dwt, where 80 make the dollar.
The US dollar of 1792 was 416 gt of std silver, or 371 gr 5 mites pure.
The Spanish dollar of eight reals, gives 550.209 gr (spanish), or 394.46 gt
The US dollar was established by the Mint Act of 1801, replaces previous
colonial money at a rate of 6s (New England, NY (state), OH) , 7s 6d
[pennsylvania, NJ, MY, DE) , 8s, (NY, much of the west) or 4s 8d (GA, SC)
(according to the state in question.
The decimal measures called for a plan where the foot was 10 inches, and a
cubic inch of water reckoned at one ounce. According to an imperial foot, and
12 gallons (US) being a cental (100 lbs.), we get the ounce as 436 4/11 grains.
In terms of sterling, this as a silver coin makes 5s.
The currency then has coins of 5s, 2s 6d, 1s 3d and 6d in silver, and a 3d
nickel coin. This explains why the nickel is four times heavier than the
corresponding silver coin.
The actual ounce used in framing the US money is the ozm (metric oz.), which is
rated at 385.809 grains. This would make the US dollar at 4s 6d. (Where most
units hight dollar were 4s. 2d. or 50 d.) This is the value it held during
most of the 19C.
By the second world war, the US dollar was rated at 5s. stg, or (according to a
book for US servicemen in australia), 6s. 3d. AU. Since the pound in Australia
is only four parts of sterlign, this also corresponds to 5s. stg.
Since the World War, the Marshall aid plan introduced to alleviate the damages
of war has seen a net export of wealth to america: that is, the USA is
currently the recieving end of large amounts of aid from the developed world.
One notes, for example, that in 1977, the US dollar traded at 9s AU, which
gives 7s. 2½d. stg. It ended up at a high of 12s. 6d. AU which is 10s. stg,
but has since "dropped into the cellar" to give 10s 6d AU, or 8s 4d stg. That
is, it is still nearly twice what it ought be.
- doubloon *
A spanish coin, of 9s. 4d. stg. This is \2 escudo, 4 peso or 32 reales.
aka Louis d'Or, Fredrich d'or, pistole,
- DSWS - Decimal SWS *
A decimalised day SWS system, using the period of time of 0.0864
The base units resemble the hand and pound, one might also make a yard-
pound-second, based on 10 hands and 10 faccs.
|length|| metre = 13.660 035 860 || foot = 4.163 578 930 683
|mass|| kilogram = 2.548 915 970 || pound = 1.156 168 835 913
|time|| second = 11.574 074 074 || day = 1 000 000.000 000
|thremm|| degC = 5 831.944 460 246 || degF = 3 239.969 2
© 2003-2004 Wendy Krieger