NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: timepiece history - when did second accuracy become feasible
From: Greg R_
Date: 2007 Oct 28, 09:58 -0800
From: Greg R_
Date: 2007 Oct 28, 09:58 -0800
> The concept of a second of time, a minute of
time as
> fractions of an hour and of a day. I wonder what civilization
> had the thought to breakdown the hour and what reasonable
> technology was available.
> fractions of an hour and of a day. I wonder what civilization
> had the thought to breakdown the hour and what reasonable
> technology was available.
I'll leave the discussion of what technology was
available (and when) to others with more resources (and more time... ;-)).
But as I understand the concept, dividing the day
up into hours was considered to be "accurate enough" for civilization a couple
hundred years ago (i.e. "We're expecting Caroline to arrive on the hour").
Then when it became necessary to divide time
into finer increments, the term "minute" was coined (as in "extremely small"),
and when a further division became necessary it was called the "second minute"
(later shortened to just "second" as we know it today).
Wonder what they'd think of our nano-, pico-, and
femto-seconds (etc.) that are in common use today?
> Among my faults, is a tendency to fall into
survival mode
> thinking. What if no battery powered timepieces, no
> computers (i.e) back to computing by hand trignometric
> tables.
> thinking. What if no battery powered timepieces, no
> computers (i.e) back to computing by hand trignometric
> tables.
What you call a "fault" I'd consider to be an
asset - someone with that "what if" mentality and mindset would be more than
welcome on any crew that I was a part of. :-)
--
GregR
----- Original Message -----From: coralline algaeTo: NavList@fer3.comSent: Sunday, October 28, 2007 7:31 AMSubject: [NavList 3676] timepiece history - when did second accuracy become feasible
This is a multipart question so I hope that I dont leave
something unasked as to the scope.
The concept of a second of time, a minute of time as
fractions of an hour and of a day. I wonder what civilization
had the thought to breakdown the hour and what reasonable
technology was available. My quess is the water clock with
the drip set to 60 per minute but this is pure speculation.
I also have to wonder what drove the person who decided
that subdividing the hour was necessary. Perhaps even
the concept of a second was quite the leap.
Since the length of the day changes throughout the year, some
technology perhaps sundials, or again water clocks made the
observer aware that measuring an hour with some measure
of accuracy was desirable. I know that on ships a sandglass
was used to to time watches.
Although Harrison was among the first to make a timepiece
of sufficient accuracy for use at sea, I wonder how much
earlier land based timepieces were up to the task.
Among my faults, is a tendency to fall into survival mode
thinking. What if no battery powered timepieces, no
computers (i.e) back to computing by hand trignometric
tables.
Peace
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---