HOW DID ANCIENTS KNOW & CALCULATE THE EQUINOX

[r6r6]

BigJohn--As already discussed several times, how can a sundial be used after the sun 'sits'?

Dont know that you need a night time piece.


Moon dial and hour glass are other possible ways to reference time to celestial events.

[BigJohn]

Originally Posted by r6r6r

Dont know that you need a night time piece.


Moon dial and hour glass are other possible ways to reference time to celestial events.

I think you forgot part (b) of the question. How did the ancients know that each day there is more or less daylight and darkness each day and it totals 24 hours? So how could they tell on the equinox's, the daylight and darkness were equal length. If they could not measure the length of darkness, they could have concluded the length of each day is different from the previous day.

[r6r6]

BigJohn--I think you forgot part (b) of the question. How did the ancients know that each day there is more or less daylight and darkness each day

Observation, sundials, hourglass time pieces and whatever other time clocks that could have been used.

and it totals 24 hours? So how could they tell on the equinox's, the daylight and darkness were equal length. If they could not measure the length of darkness, they could have concluded the length of each day is different from the previous day.

Ditto my above and all of my previous posts adn here is link to others that we know of.

https://en.wikipedia.org/wiki/Histor...eeping_devices


Sun Clocks

..'The Sumerian culture was lost without passing on its knowledge, but the Egyptians were apparently the next to formally divide their day into parts something like our hours. Obelisks (slender, tapering, four-sided monuments) were built as early as 3500 BCE. Their moving shadows formed a kind of sundial, enabling people to partition the day into morning and afternoon. Obelisks also showed the year's longest and shortest days when the shadow at noon was the shortest or longest of the year. Later, additional markers around the base of the monument would indicate further subdivisions of time.

[BigJohn]

Gee.... the Sumerians are noted for using the base 60 number system. It is a toss up which came first: base 60 or base 10. In some parts of the World, base 60 is still used by some merchants. At times, I enjoy using base 60.

Remnants of base 60 are found in time and navigation. If a person goes to 5 places, using time and navigation based on base 60, a person can calculate how to get from the last place to the start place and if they travel at a constant speed, how long it will take to get back to the starting location.

At one time, I was fascinated with base 60 but then I have worked with numerous other number bases. For example, one project I did, I worked with octal, tri-octal, binary and hexadecimal. A nice exercise is to try working with numbers in one base and then convert them to another base.

[Gem]

Originally Posted by BigJohn

Without a time piece, how do you find the longest and shortest day?
Besides, how did they realize the hours of day light were not the same every day?
For me, it is a very difficult question.

The simplest way would be to note where the sun sets and rises everyday, and realise there is a pattern of the sun swinging from right to left, and it draws high and low arcs on the sky. It's relatively easy to establish the equinoxes in this way, within a few days at least, without having a counting system to measure number of days or hours therein. People would notice the days became longer and shorter without time pieces, and it's likely the chronology by which time was perceived would have been different to our modern method of counted time intervals. No doubt the old peoples' representations of time was less accurate than our modern use of atomic clocks etc, but they did not need accurate measures back then.

Originally Posted by BigJohn

Without a time piece, how do you find the longest and shortest day?
Besides, how did they realize the hours of day light were not the same every day?
For me, it is a very difficult question.

I live in north east Scotland in a small town that's traditionally fishing and farming, so most folks around here take notice of things like daylight hours and weather patterns, the changing of the seasons.... At the summer Solstice we have a handful of hours of darkness and winter Solstice gives a handful of hours of daylight. There's a noticeable difference even just after the Solstice when the days become either shorter or longer and no timepiece is needed. Perhaps megalithic man noticed the changes in daylight hours and devised a way to measure them more accurately, in the same way as he noticed the sun creeping across the sky over the course of the year.

[BigJohn]

Originally Posted by Gem

The simplest way would be to note where the sun sets and rises everyday, and realise there is a pattern of the sun swinging from right to left, and it draws high and low arcs on the sky. It's relatively easy to establish the equinoxes in this way, within a few days at least, without having a counting system to measure number of days or hours therein. People would notice the days became longer and shorter without time pieces, and it's likely the chronology by which time was perceived would have been different to our modern method of counted time intervals. No doubt the old peoples' representations of time was less accurate than our modern use of atomic clocks etc, but they did not need accurate measures back then.

You are right.

Then the idea was added of the importance of the equinox: equal daylight and darkness which also brings up the point that the length of daylight per day are different for each day except for on the 2 equinoxes. How could the ancients resolve this? They would need to be able to calculate time. As for calculating time, one method was mentioned in post # 28.

Ever once in a while, I would become fascinated with time. For example, I almost bought a 18th century watch: only one hand. Then there was my interest in solar time which the railroads use to go by till we got the form of counting time we have today: time zones. Lets not forget that the second and minute are based from base 60 which also gave us the 12 used in 12 hours and another 12 hours. If you become familiar as to how some merchants of today use base 60 in sale transactions: 12 plays a major role.

[BigJohn]

Originally Posted by Greenslade

I live in north east Scotland in a small town that's traditionally fishing and farming, so most folks around here take notice of things like daylight hours and weather patterns, the changing of the seasons.... At the summer Solstice we have a handful of hours of darkness and winter Solstice gives a handful of hours of daylight. There's a noticeable difference even just after the Solstice when the days become either shorter or longer and no timepiece is needed. Perhaps megalithic man noticed the changes in daylight hours and devised a way to measure them more accurately, in the same way as he noticed the sun creeping across the sky over the course of the year.

NICE COMMENT

On post # 28, a workable method of time was given.

Were I live, the Apaches built structures that are aligned by the equinoxes. The Jews knew about it so they
could calculate their New Year's first month, Nisan, in which they derived when the Passover would occur.

[John32241]

Originally Posted by BigJohn

At one time, I was fascinated with base 60 but then I have worked with numerous other number bases. For example, one project I did, I worked with octal, tri-octal, binary and hexadecimal. A nice exercise is to try working with numbers in one base and then convert them to another base.

Hi,

I have done my fair share of assembler programming. Binary concepts are important to appreciate when dealing with electronics.

The place for base 12 math is in physics. I was not aware there was a base 60 system. In physics there is the need for matching the number of elements and concluding the relationship. Since nature works in base 12 math with a lot of 3's, 4's, and 6's it only seems reasonable to me we would want to think in those terms instead of base 10 like we do now. In my mind the ancients were closer to nature and understood things better than we do today.

As far as computers are concerned, our 64 bit processors of today are not effective. The registers these chips use are 1 byte, 2 byte, 4 byte, and 8 bytes mostly. There is no effective way to deal with storage sizes of 3, 5, 6, & 7 bytes. Not to mention the great liability that all boolian data must be stored 2 byte fields of information. A great deal of programming logic is yes/no boolian dependant. Yet we do not have really good ways to work with it.

I first worked with assembler in 1965-1966. It was called FAP. Fortran Assembly programming. Then again in 1975-1976 with BAL. Basic assembler language. My most recent experience has been with FASM. That runs on the current x86 chip sets. I mostly use the higher level languages because assembler does not have a user friendly interface. However the day it can work directly with a browser like front end I will be a big advocate for it.

John

[BigJohn]

I can relate to what you are saying.

In my playful moments, I talk about 2 bits which can also be a quarter (25 cents)
and in 1881 you could get two glasses of whiskey for 2 bits (quarter)

Then there is 4 bits which is a nibble (binary).

2 nibbles, which is 8 bits, makes a byte.

2 bytes, which is 16 bits, is a word (binary)

Do you remember how data was "packed"

Interesting you brought up the x86 chip sets which it seems most programs are compiled using that chip set instructions. The 8086 microprocessor came out in the 1970's.... and apparently most of our programs are still using that limited instruction set.