Michael Koblic wrote:

"J Burns" wrote in message
...


After I pressed SEND, I saw that I'd misread you. Well, a sundial
takes more than two pieces of wood. A shadow clock is easy to make
and mark.

Not true. An equatorial dial can be made from a flat board and a stick.
It is inherently more accurate than the said stick and considerably
easier to "calibrate".

Putting sticks together with right angles and measuring millimeters to
make four marks is easier than inscribing and marking arcs on a board
and setting a gnomon at a particular angle.



However, it looks excellent for dividing the daylight into 12 hours.
That was what people wanted before mechanical timers and neon
lights. The shadow clock handled "daylight savings" beautifully. In
Cairo, summer hours were 70 minutes and winter hours 51 minutes,
changing gradually through the year.

Yes. And you can also discuss Babylonian hours, Italian hours etc.
You can measure anything with anything if you define the quantities
any way
you want. If you want to measure recognized quantities, however, you
have to follow
some constraints. This shadow stick does not do that.

In that case, I think a clock must have a digital display, a stopwatch
with 99 lap times, a countdown timer, a calendar, and an alarm. Your
sundial does none of that.

No, all it has to do is measure time in equal increments . The shadow
stick *shown* does not do that.

I'm talking about *real* shadow clocks, used to this day.


The Jewish calender used equal increments: lunar months. They Egyptian
calendar used a 365-day year. Our calendar does not have equal months
or years. Does that mean it's not a real calendar?


A shadow clock would show hours as mentioned in the Bible: divisions
of the time between sunup and sundown.

Egyptian monuments had east-west walls. All you had to do was spot
such a landmark, move until you were looking along an east-west
wall, shim your card table so your wine jug didn't roll off, put
your shadow clock on the table, and aim it at the landmark. The
shadow would tell you the time of day (accurate within minutes
throughout the year) and if the livestock dealer who had agreed to
show you his ass was late.

Depends which side of the east-west wall you park your table. You
could be
out of luck on the north side. Also you calculations above do not really
support the accuracy statement.

If you were on the north side of an east-west wall, you wouldn't be
looking along it, would you?

I calculated the accuracy of a shadow clock marked for 60-minute hours
in Cairo at equinox.

summer solstice: day length 838 minutes, mean hour 70 minutes

dawn first second third fourth fifth sixth noon
62 66 69 74 73 75

winter solstice: day length 604 minutes, mean hour 50 minutes

dawn first second third fourth fifth sixth noon
57 54 51 49 42 49

So even at the solstices, the hours are within 8 minutes of 1/12th of
a day.

Are you saying that these figures correspond to the equal divisions on
the shadow stick? I do not think so.

You're catching on. Although you answered several of my posts where I
showed the calculated measurements, apparently you did not read them.

Furthermore, for the stick to show
"6 o'clock" correctly the stick would have to be several yards long to
even catch the end of the shadow.

That's why I said "counting direct observations of the sun." A farmer
doesn't need a shadow clock to see when the sun rises and sets.

Sun's altitude in Cairo at summer
solstice is about 11 degrees (various calculators give slightly
different results).

You lost me there.

Given that on the same day at noon the sun is about
84 degrees high the noon to 6 interval is whopping 43 times that of noon
to 1.

Counting direct observations of the sun, the hours were numbered from
sunup to sundown, which would suit an ancient farmer. It was far
easier to make and set up than a sun dial. The shadow of the edge of
a T on a bar could probably be read more precisely than a sundial.

Why? Which sundial?

The edge of a T casts a shadow through an angle of less than 90 degrees.
A gnomon casts a shadow as the sun moves more than 180 degrees. That
sounds like a source of error.


As I said before, you can measure anything if you make up your own
definitions.


I believe you're making up your own definitions. The Egyptians used a
10-hour day and a 12-hour night. At night they used celestial
observations. If you want time in equal divisions, hourglasses synced
with celestial observations is much better than sundials. If you want
to divide the day into 10 hours, a sundial won't do it.


Finally, here is what I take to be the artifacts themselves:

http://members.aon.at/sundials/berlin-egypt_e.htm

The labeling is somewhat confusing in places but I think in general the
pictures and the description are fairly conclusive.

Here's a page for you.
http://library.thinkquest.org/C00817...ichistory.html

" The Egyptians were the first people who created a twenty-four hour
day. Time was a little bit different in those days. The night was
divided up into twelve hours, which were designated by the position of
stars in the sky. The day was divided into ten hours and a shadow clock
was used to keep track of these hours. The twilight hours were the
hours before dawn and after sunset."

" The Egyptians thought they were the first to invent the shadow
clock, but they were mistaken. At the same time, the Chinese,
Babylonians, Greeks and the Romans were using instruments to tell time.
Sundials were used in some of these groups, not because they work
better, just because that's how they decided to tell time."

On Aug 11, 1:10*am, J Burns wrote:
Michael Koblic wrote:

"J Burns" wrote in message
...

After I pressed SEND, I saw that I'd misread you. *Well, a sundial
takes more than two pieces of wood. *A shadow clock is easy to make
and mark.

Not true. An equatorial dial can be made from a flat board and a stick.
It is inherently more accurate than the said stick and considerably
easier to "calibrate".

Putting sticks together with right angles and measuring millimeters to
make four marks is easier than inscribing and marking arcs on a board
and setting a gnomon at a particular angle.







However, it looks excellent for dividing the daylight into 12 hours.
That was what people wanted before mechanical timers and neon
lights. The shadow clock handled "daylight savings" beautifully. *In
Cairo, summer hours were 70 minutes and winter hours 51 minutes,
changing gradually through the year.

Yes. And you can also discuss Babylonian hours, Italian hours etc.
You can measure anything with anything if you define the quantities
any way
you want. If you want to measure recognized quantities, however, you
have to follow
some constraints. This shadow stick does not do that.

In that case, I think a clock must have a digital display, a stopwatch
with 99 lap times, a countdown timer, a calendar, and an alarm. *Your
sundial does none of that.

No, all it has to do is measure time in equal increments . The shadow
stick *shown* does not do that.

I'm talking about *real* shadow clocks, used to this day.

The Jewish calender used equal increments: lunar months. *They Egyptian
calendar used a 365-day year. *Our calendar does not have equal months
or years. *Does that mean it's not a real calendar?







A shadow clock would show hours as mentioned in the Bible: divisions
of the time between sunup and sundown.

Egyptian monuments had east-west walls. *All you had to do was spot
such a landmark, move until you were looking along an east-west
wall, shim your card table so your wine jug didn't roll off, put
your shadow clock on the table, and aim it at the landmark. *The
shadow would tell you the time of day (accurate within minutes
throughout the year) and if the livestock dealer who had agreed to
show you his ass was late.

Depends which side of the east-west wall you park your table. You
could be
out of luck on the north side. Also you calculations above do not really
support the accuracy statement.

If you were on the north side of an east-west wall, you wouldn't be
looking along it, would you?

I calculated the accuracy of a shadow clock marked for 60-minute hours
in Cairo at equinox.

summer solstice: day length 838 minutes, mean hour 70 minutes

dawn first * second *third fourth fifth sixth noon
* * * 62 * * * 66 * * 69 * *74 * * 73 * *75

winter solstice: day length 604 minutes, mean hour 50 minutes

dawn first * second *third fourth fifth sixth noon
* * * 57 * * * 54 * * 51 * * 49 * *42 * *49

So even at the solstices, the hours are within 8 minutes of 1/12th of
a day.

Are you saying that these figures correspond to the equal divisions on
the shadow stick? I do not think so.

You're catching on. *Although you answered several of my posts where I
showed the calculated measurements, apparently you did not read them.

Furthermore, for the stick to show
"6 o'clock" correctly the stick would have to be several yards long to
even catch the end of the shadow.

That's why I said "counting direct observations of the sun." *A farmer
doesn't need a shadow clock to see when the sun rises and sets.

Sun's altitude in Cairo at summer
solstice is about 11 degrees (various calculators give slightly
different results).

You lost me there.

Given that on the same day at noon the sun is about
84 degrees high the noon to 6 interval is whopping 43 times that of noon
to 1.

Counting direct observations of the sun, the hours were numbered from
sunup to sundown, which would suit an ancient farmer. *It was far
easier to make and set up than a sun dial. *The shadow of the edge of
a T on a bar could probably be read more precisely than a sundial.

Why? Which sundial?

The edge of a T casts a shadow through an angle of less than 90 degrees.
* A gnomon casts a shadow as the sun moves more than 180 degrees. *That
sounds like a source of error.



As I said before, you can measure anything if you make up your own
definitions.

I believe you're making up your own definitions. *The Egyptians used a
10-hour day and a 12-hour night. *At night they used celestial
observations. *If you want time in equal divisions, hourglasses synced
with celestial observations is much better than sundials. *If you want
to divide the day into 10 hours, a sundial won't do it.



Finally, here is what I take to be the artifacts themselves:

http://members.aon.at/sundials/berlin-egypt_e.htm

The labeling is somewhat confusing in places but I think in general the
pictures and the description are fairly conclusive.

Here's a page for you.http://library.thinkquest.org/C00817...ichistory.html

" * The Egyptians were the first people who created a twenty-four hour
day. *Time was a little bit different in those days. *The night was
divided up into twelve hours, which were designated by the position of
stars in the sky. *The day was divided into ten hours and a shadow clock
was used to keep track of these hours. *The twilight hours were the
hours before dawn and after sunset."

" * The Egyptians thought they were the first to invent the shadow
clock, but they were mistaken. *At the same time, the Chinese,
Babylonians, Greeks and the Romans were using instruments to tell time.
* Sundials were used in some of these groups, not because they work
better, just because that's how they decided to tell time."

Well, its not rocket science, but if you google "shadow clock" you get
some very good pictures and websites discussing them. So either
everyone out there is wrong, or a couple of folks here are.

--riverman

riverman wrote:
On Aug 11, 1:10 am, J Burns wrote:
Michael Koblic wrote:

"J Burns" wrote in message
...
After I pressed SEND, I saw that I'd misread you. Well, a sundial
takes more than two pieces of wood. A shadow clock is easy to make
and mark.
Not true. An equatorial dial can be made from a flat board and a stick.
It is inherently more accurate than the said stick and considerably
easier to "calibrate".
Putting sticks together with right angles and measuring millimeters to
make four marks is easier than inscribing and marking arcs on a board
and setting a gnomon at a particular angle.







However, it looks excellent for dividing the daylight into 12 hours.
That was what people wanted before mechanical timers and neon
lights. The shadow clock handled "daylight savings" beautifully. In
Cairo, summer hours were 70 minutes and winter hours 51 minutes,
changing gradually through the year.
Yes. And you can also discuss Babylonian hours, Italian hours etc.
You can measure anything with anything if you define the quantities
any way
you want. If you want to measure recognized quantities, however, you
have to follow
some constraints. This shadow stick does not do that.
In that case, I think a clock must have a digital display, a stopwatch
with 99 lap times, a countdown timer, a calendar, and an alarm. Your
sundial does none of that.
No, all it has to do is measure time in equal increments . The shadow
stick *shown* does not do that.
I'm talking about *real* shadow clocks, used to this day.

The Jewish calender used equal increments: lunar months. They Egyptian
calendar used a 365-day year. Our calendar does not have equal months
or years. Does that mean it's not a real calendar?







A shadow clock would show hours as mentioned in the Bible: divisions
of the time between sunup and sundown.
Egyptian monuments had east-west walls. All you had to do was spot
such a landmark, move until you were looking along an east-west
wall, shim your card table so your wine jug didn't roll off, put
your shadow clock on the table, and aim it at the landmark. The
shadow would tell you the time of day (accurate within minutes
throughout the year) and if the livestock dealer who had agreed to
show you his ass was late.
Depends which side of the east-west wall you park your table. You
could be
out of luck on the north side. Also you calculations above do not really
support the accuracy statement.
If you were on the north side of an east-west wall, you wouldn't be
looking along it, would you?
I calculated the accuracy of a shadow clock marked for 60-minute hours
in Cairo at equinox.
summer solstice: day length 838 minutes, mean hour 70 minutes
dawn first second third fourth fifth sixth noon
62 66 69 74 73 75
winter solstice: day length 604 minutes, mean hour 50 minutes
dawn first second third fourth fifth sixth noon
57 54 51 49 42 49
So even at the solstices, the hours are within 8 minutes of 1/12th of
a day.
Are you saying that these figures correspond to the equal divisions on
the shadow stick? I do not think so.
You're catching on. Although you answered several of my posts where I
showed the calculated measurements, apparently you did not read them.

Furthermore, for the stick to show
"6 o'clock" correctly the stick would have to be several yards long to
even catch the end of the shadow.
That's why I said "counting direct observations of the sun." A farmer
doesn't need a shadow clock to see when the sun rises and sets.

Sun's altitude in Cairo at summer
solstice is about 11 degrees (various calculators give slightly
different results).
You lost me there.

Given that on the same day at noon the sun is about
84 degrees high the noon to 6 interval is whopping 43 times that of noon
to 1.
Counting direct observations of the sun, the hours were numbered from
sunup to sundown, which would suit an ancient farmer. It was far
easier to make and set up than a sun dial. The shadow of the edge of
a T on a bar could probably be read more precisely than a sundial.
Why? Which sundial?
The edge of a T casts a shadow through an angle of less than 90 degrees.
A gnomon casts a shadow as the sun moves more than 180 degrees. That
sounds like a source of error.



As I said before, you can measure anything if you make up your own
definitions.
I believe you're making up your own definitions. The Egyptians used a
10-hour day and a 12-hour night. At night they used celestial
observations. If you want time in equal divisions, hourglasses synced
with celestial observations is much better than sundials. If you want
to divide the day into 10 hours, a sundial won't do it.



Finally, here is what I take to be the artifacts themselves:
http://members.aon.at/sundials/berlin-egypt_e.htm
The labeling is somewhat confusing in places but I think in general the
pictures and the description are fairly conclusive.
Here's a page for you.http://library.thinkquest.org/C00817...ichistory.html

" The Egyptians were the first people who created a twenty-four hour
day. Time was a little bit different in those days. The night was
divided up into twelve hours, which were designated by the position of
stars in the sky. The day was divided into ten hours and a shadow clock
was used to keep track of these hours. The twilight hours were the
hours before dawn and after sunset."

" The Egyptians thought they were the first to invent the shadow
clock, but they were mistaken. At the same time, the Chinese,
Babylonians, Greeks and the Romans were using instruments to tell time.
Sundials were used in some of these groups, not because they work
better, just because that's how they decided to tell time."

Well, its not rocket science, but if you google "shadow clock" you get
some very good pictures and websites discussing them. So either
everyone out there is wrong, or a couple of folks here are.

--riverman

Wrong about what?

"J Burns" wrote

Wrong about what?

What is really wrong is that nobody in this thread over the past several
posts has taken the time to trim out all the totally unnecessary previous
posts. Sombody please step up, next time?

8 kb for a three word reply? Really?
--
Jim in NC

These are usually the ones that whine about their reader not understanding
top posting.

Just plain laziness.


"Morgans" wrote in message
...
What is really wrong is that nobody in this thread over the past several
posts has taken the time to trim out all the totally unnecessary previous
posts. Sombody please step up, next time?

8 kb for a three word reply? Really?
--
Jim in NC



"J Burns" wrote

Wrong about what?



--
Have your accounts been removed by other's complaints?
Do you like to force your opinions on others?
Do you need to use multiple names due to shame and fear?
Better rates for those requiring anonymity to survive!
******** easynews.com, trolling made easy **********

On 08/11/2010 10:13 PM, Josepi wrote:
These are usually the ones that whine about their reader not understanding
top posting.

Just plain laziness.

Congratulations. That far and away takes the cake as the stupidest post I've read all day.

--
Free bad advice available here.
To reply, eat the taco.
http://www.flickr.com/photos/bbqboyee/

Josepi wrote:
These are usually the ones that whine about their reader not understanding
top posting.

Just plain laziness.
....

More like plain rudeness... (including top-posting)

--

Morgans wrote:
"J Burns" wrote

Wrong about what?

What is really wrong is that nobody in this thread over the past several
posts has taken the time to trim out all the totally unnecessary previous
posts. Sombody please step up, next time?

8 kb for a three word reply? Really?

I did not know what Riverman's remark had to do with the topic.
Something about everybody with a web page agreeing on something and two
unnamed people being wrong. I left the material he quoted so he could
point it out.

Your trimming leaves no connection to the topic. You really should have
started a new thread and marked it OT.

On Aug 12, 8:56*am, J Burns wrote:
riverman wrote:
On Aug 11, 1:10 am, J Burns wrote:
Michael Koblic wrote:

"J Burns" wrote in message
...
After I pressed SEND, I saw that I'd misread you. *Well, a sundial
takes more than two pieces of wood. *A shadow clock is easy to make
and mark.
Not true. An equatorial dial can be made from a flat board and a stick.
It is inherently more accurate than the said stick and considerably
easier to "calibrate".
Putting sticks together with right angles and measuring millimeters to
make four marks is easier than inscribing and marking arcs on a board
and setting a gnomon at a particular angle.

However, it looks excellent for dividing the daylight into 12 hours.
That was what people wanted before mechanical timers and neon
lights. The shadow clock handled "daylight savings" beautifully. *In
Cairo, summer hours were 70 minutes and winter hours 51 minutes,
changing gradually through the year.
Yes. And you can also discuss Babylonian hours, Italian hours etc.
You can measure anything with anything if you define the quantities
any way
you want. If you want to measure recognized quantities, however, you
have to follow
some constraints. This shadow stick does not do that.
In that case, I think a clock must have a digital display, a stopwatch
with 99 lap times, a countdown timer, a calendar, and an alarm. *Your
sundial does none of that.
No, all it has to do is measure time in equal increments . The shadow
stick *shown* does not do that.
I'm talking about *real* shadow clocks, used to this day.

The Jewish calender used equal increments: lunar months. *They Egyptian
calendar used a 365-day year. *Our calendar does not have equal months
or years. *Does that mean it's not a real calendar?

A shadow clock would show hours as mentioned in the Bible: divisions
of the time between sunup and sundown.
Egyptian monuments had east-west walls. *All you had to do was spot
such a landmark, move until you were looking along an east-west
wall, shim your card table so your wine jug didn't roll off, put
your shadow clock on the table, and aim it at the landmark. *The
shadow would tell you the time of day (accurate within minutes
throughout the year) and if the livestock dealer who had agreed to
show you his ass was late.
Depends which side of the east-west wall you park your table. You
could be
out of luck on the north side. Also you calculations above do not really
support the accuracy statement.
If you were on the north side of an east-west wall, you wouldn't be
looking along it, would you?
I calculated the accuracy of a shadow clock marked for 60-minute hours
in Cairo at equinox.
summer solstice: day length 838 minutes, mean hour 70 minutes
dawn first * second *third fourth fifth sixth noon
* * * 62 * * * 66 * * 69 * *74 * * 73 * *75
winter solstice: day length 604 minutes, mean hour 50 minutes
dawn first * second *third fourth fifth sixth noon
* * * 57 * * * 54 * * 51 * * 49 * *42 * *49
So even at the solstices, the hours are within 8 minutes of 1/12th of
a day.
Are you saying that these figures correspond to the equal divisions on
the shadow stick? I do not think so.
You're catching on. *Although you answered several of my posts where I
showed the calculated measurements, apparently you did not read them.

Furthermore, for the stick to show
"6 o'clock" correctly the stick would have to be several yards long to
even catch the end of the shadow.
That's why I said "counting direct observations of the sun." *A farmer
doesn't need a shadow clock to see when the sun rises and sets.

Sun's altitude in Cairo at summer
solstice is about 11 degrees (various calculators give slightly
different results).
You lost me there.

Given that on the same day at noon the sun is about
84 degrees high the noon to 6 interval is whopping 43 times that of noon
to 1.
Counting direct observations of the sun, the hours were numbered from
sunup to sundown, which would suit an ancient farmer. *It was far
easier to make and set up than a sun dial. *The shadow of the edge of
a T on a bar could probably be read more precisely than a sundial.
Why? Which sundial?
The edge of a T casts a shadow through an angle of less than 90 degrees.
* A gnomon casts a shadow as the sun moves more than 180 degrees. *That
sounds like a source of error.

As I said before, you can measure anything if you make up your own
definitions.
I believe you're making up your own definitions. *The Egyptians used a
10-hour day and a 12-hour night. *At night they used celestial
observations. *If you want time in equal divisions, hourglasses synced
with celestial observations is much better than sundials. *If you want
to divide the day into 10 hours, a sundial won't do it.

Finally, here is what I take to be the artifacts themselves:
http://members.aon.at/sundials/berlin-egypt_e.htm
The labeling is somewhat confusing in places but I think in general the
pictures and the description are fairly conclusive.
Here's a page for you.http://library.thinkquest.org/C00817...ichistory.html

" * The Egyptians were the first people who created a twenty-four hour
day. *Time was a little bit different in those days. *The night was
divided up into twelve hours, which were designated by the position of
stars in the sky. *The day was divided into ten hours and a shadow clock
was used to keep track of these hours. *The twilight hours were the
hours before dawn and after sunset."

" * The Egyptians thought they were the first to invent the shadow
clock, but they were mistaken. *At the same time, the Chinese,
Babylonians, Greeks and the Romans were using instruments to tell time..
* Sundials were used in some of these groups, not because they work
better, just because that's how they decided to tell time."

Well, its not rocket science, but if you google "shadow clock" you get
some very good pictures and websites discussing them. So either
everyone out there is wrong, or a couple of folks here are.

--riverman

Wrong about what?

I was reading an unspoken inference that this thing wasn't really for
telling time, as it would be too inaccurate to be useful.

--riverman

riverman wrote:
On Aug 12, 8:56 am, J Burns wrote:

Wrong about what?

I was reading an unspoken inference that this thing wasn't really for
telling time, as it would be too inaccurate to be useful.

--riverman

I like what library.thinkquest.org said, that the sundial wasn't
necessarily better.

For centuries, longitudes in the New World were unknown because ships
didn't know the "real time." Still, sailors turning hourglasses
maintained watch schedules.

When I was a kid in Rutland VT, the fire whistle blew daily at 8:50 AM
and 8:50 PM. The morning whistle told every kid it was time to get to
school. The evening whistle said it was time to get home. I'd say
those whistles functioned like marks on a shadow clock.