Once a upon a time someone invented the clock.

For years we had been using the sun to tell the time –

Midday when the sun was highest in the sky each day

Midsummer when it was the highest in the sky in the year

Summer and winter solstice being highest and lowest points of the year

We split up the day and years with the help of sundials

Small ones like you see in the garden or big ones such as Stonehenge.

The inventors of the clock thought they could help people tell the time

– it would be especially useful when the sun was not out such as rainy days or at night

This worked very well for years – until someone noticed

that the clocks were no longer matching the sun

Investigations ensued to find out why

And then a solution needed to be found

And corrections made

Why

The sun year, based on the earth’s orbit around the sun, is 365.2422 days long (365 days, 5 hours, 48 minutes and 46 seconds)

The human created calendar is exactly 365 days long

Solution

Add in extra day(s) in February

E.g. one every 4 years – hence 29^th February

But this is not quite accurate enough

You also need to leave one out about every 100 years

Fix

Roman calendars had eleven months of 29 or 31 days, plus February with 28 days or 23 days if a thirteenth month of 27 or 28 days were added to try to keep in line with the solar calendar. All very