See Peary's measurements of depth on page three:
http://www.northpole1909.com/davies.html
gl
--- On Mon, 3/5/12, Lu Abel <luabel@ymail.com> wrote:
From: Lu Abel <luabel@ymail.com>
Subject: [NavList] Re: About time - Antarctica
To: "NavList@fer3.com" <NavList@fer3.com>
Date: Monday, March 5, 2012, 11:29 AM
Good question. Or, for that matter, when they say the Marianas Trench is 35,000 feet deep, how did they measure that? Too far, I would presume, for
sonar.
Lu
From: Bruce Pennino <bpennino.ce@charter.net>
To: NavList@fer3.com
Sent:
Monday, March 5, 2012 10:49 AM
Subject: [NavList] Re: About time - Antarctica
They were measuring 1000s of feet of depth. How
could they "feel" when the object touched or bounced off the
bottom?
Bruce J. Pennino, P.E.
----- Original Message -----
Sent: Monday, March 05, 2012 12:27
PM
Subject: [NavList] Re: About time -
Antarctica
Very much like using a hand lead line except it was a
much heavier weight on a long wire which was on a motorized reel. This
device was called a "deep sea lead."
gl
--- On Mon,
3/5/12, Bruce Pennino <bpennino.ce@charter.net>
wrote:
From:
Bruce Pennino <bpennino.ce@charter.net>
Subject:
[NavList] About time - Antarctica
To:
NavList@fer3.com
Date: Monday, March 5, 2012, 7:50 AM
Just finished reading The Storied Ice by
Joan Boothe. A very good overview book about all
major explorations of Antarctica; many references.
Anyway, Antarctica explorers had a
longitude problem. In 1926-27 the Discovery "was the first vessel in
these waters capable of receiving Greenwich time signals directly, and
her men used the signals to check longitudinal positions on the
maps." Only Deception Island was properly
located.
Also,as the early explorers headed south
,they measured water depth for various reasons. How did they measure
depths of several thousand feet with a drifting ship, angle of cable,
flexibility(springiness)?
Boothe gives a brief overview of Cook's
explorations....she says he was an extraordinary
man.
Bruce Pennino
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