**Kalentris** is a calendar invented by an *unknown person* that is heavily based upon the number 3. It has months of 27 days of which exactly 5411 occur in one Gregorian 400-year cycle, but has no rule for grouping these 5411 months into 400 years. Instead it has a year of exactly 9 months = 243 days.

## Temporal units[]

- 3
^{0} - A
*day*has 86400 SI seconds.

- 3
^{1} - A
*tierce*has three days. One of which is the weekly vacation (“weekend”) in industrialised countries; at eight hours of work per day this compares to about seven and a half hours in the current 5+2 system. - 3
^{2} - A
*week*has three tierces (9 days). - 3
^{3} - A
*month*has three weeks (27 days). - 3
^{4} - A
*tertiade*or*tertial*has three months (81 days). - 3
^{5} - A
*year*has three tertiades (243 days). - 3
^{6} - A
*tricycle*has three years, or 27 months of 27 days each of 27 hours each. It is thus a time span of 729 days, i.e. almost two traditional years (730 d or 731 d; mean 730.485 d). The leap rule is binary-decimal: after each odd tricycle there is a*leap tierce*, but not after odd-hundredth tricycle. Thus 200 tricycles or 600 years exactly match 400 Gregorian years (146097 days).

- 3
^{−1} - A
*shift*is one third of a day (8:00:00). - 3
^{−2} - A
*watch*is one third of a shift (2:40:00). - 3
^{−3} - An
*hour*is one third of a watch. This hour is exactly 8/9th of the traditional one (0:53:40). - 3
^{−4} - A
*tierce*is one third of an hour (~ 0:17:47). - 3
^{−5} - A
*break*is one third of a tierce (< 0:06:00). - 3
^{−6} - A
*boil*is one third of a break. One minute is 0.50625 boils exactly. - 3
^{−7} - A
*come*is one third of a boil (~ 0:00:40). - 3
^{−8} - A
*run*is one third of a come. - 3
^{−9} - A
*moment*is one third of a run. - 3
^{−10} - A
*blink*is one third of a moment (< 0:00:01.5). - 3
^{−11} - A
*tick*is one third of a blink and the smallest named unit of time. One SI second is 2.0503125 ticks exactly.

### See also[]

- Trical, a similar calendar

## Notation[]

The tertiary digits used for date and time notation are, in ascending order, ‘-’, ‘o’ and ‘+’. There is also an associated alphabet of 27 characters which can be used to compress groups of three items and the common digits 1–9 may be used for groups of two items, if there is an established convention to do so. Tricycles are counted decimally with the traditional digits from 0 through 9.

## Derived system of measurement[]

There is an optional system of (basic) measurement derived from the temporal units.

### Length[]

- 3
^{0} - A
*step*is defined by the speed of light in vacuum which is exactly 3^{18}steps per blink. It is therefore about 0.7738 metres (or 30.47 inches).

- 3
^{−1} - A
*foot*is one third of a step. - 3
^{−2} - A
*palm*is one third of a foot. - 3
^{−3} - A
*inch*is one third of a palm. - 3
^{−4} - A
*nail*is one third of an inch, about 1 cm. - 3
^{−5} - A
*pim*is one third of a nail. - 3
^{−6} - A
*line*is one third of a pim, about 1 mm. - 3
^{−7} - A
*point*is one third of a line.

- 3
^{1} - A
*fathom*has three steps. - 3
^{2} - A
*rod*has three fathoms. - 3
^{3} - A
*chain*or*shackle*has three rods. - 3
^{4} - A
*sprint*has three chains. - 3
^{5} - A
*fur*has three sprints. - 3
^{6} - A
*lee*has three furs. - 3
^{7} - A
*mile*has three lees, about one statute mile. - 3
^{8} - A
*league*has three miles, about 5 km. - 3
^{9} - A
*mart*has three leagues. - 3
^{10} - A
*distance*has three marts.

### Area[]

- 3
^{0} - A
*square*is a square step. - 3
^{1} - A
*cord*has three squares. - 3
^{6} - A square chain.
- 3
^{7} - A
*rood*has three square chains. - 3
^{8} - An
*acre*has three roods, is a square sprint.

### Volume[]

- 3
^{0} - A
*pipe*or*butt*is a cubic step. - 3
^{−1} - A
*barrel*is one third of a pipe. - 3
^{−2} - A
*firkin*or*bushel*is one third of a barrel. - 3
^{−3} - A
*ken*is one third of a firkin. - 3
^{−4} - A
*gallon*is one third of a ken. - 3
^{−5} - A
*pottle*is one third of a gallon. - 3
^{−6} - A
*pint*is one third of a pottle. - 3
^{−7} - A
*cup*is one third of a pint. - 3
^{−8} - A
*gill*is one third of a cup. - 3
^{−9} - An
*ounce*is one third of a gill. - 3
^{−10} - A
*spoon*is one third of an ounce. - 3
^{−11} - A
*dram*is one third of a spoon. - 3
^{−12} - A
*spit*is one third of a dram.