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Subject: Re: Logs
From: Mitch Burrill (MBurrill@XXX.XXX)
Date: Tue Jun 10 2003 - 15:29:19 EDT
The book "Latitude Hooks and Azimuth Rings" has a basic version with how-to. I constructed the weatherglass and it worked well. From Amazon.com
-----Original Message-----
From: Vic Fraenckel [mailto:vfraenc1@XXX.XXX]
Sent: Tuesday, June 10, 2003 3:21 PM
To: NAVIGATION-L@XXX.XXX
Subject: Logs
As anyone who has read Patrick O'Brien's Aubrey/Maturin novels knows, the
use of a log line is often mentioned. It is essentially a board with a
bridle and a long knotted line on a reel. I surmise that the bridle was used
to keep the face of the board perpindicular to the water flow in order to
maximize the drag on the log. It was the midshipman of the watch to use the
log to ascertain the speed of the vessel at periodic intervals. I am sure I
am not telling members of this list anything they do not know! I would like
to duplicate this speed log for my own sailboat. I understand that the log
was tossed overboard and a 30 second sandglass was turned. The board pulled
the knotted line off the reel and the mid counted the knots that passed thru
his fingers during the 30 second interval. He then nipped the line which
caused the board to become more streamlined (parallel to the flow) in the
water and the line was reeled in. The number of knots counted equalled the
speed.
Is there a description somewhere that would tell me how to duplicate such a
log?
Any enlightenment will be appreciated.
TIA
Vic
________________________________________________________
Victor Fraenckel - The Windman vfraenc1@XXX.XXX
KC2GUI www.windsway.com
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