NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Silicon Sea charts
From: W Murfin
Date: 1997 Mar 10, 19:55 EST
From: W Murfin
Date: 1997 Mar 10, 19:55 EST
Charts for upcoming legs of Silicon Sea have been posted at the
Ronin ftp site. They can be downloaded by ftp or with a web browser using
the URL ftp://ftp.ronin.com/incoming. This is easy to do with Netscape. It
automatically displays the graphic file and you may be able to print it
directly from Netscape. If you use an ftp program or some other web browser
you may need a program to view and print gif coded files. A freeware viewer
program for Windows is also available at ftp.ronin.com/incoming under
lview.zip. The Silicon Sea chart files are:
egypt.gif - approach to Egypt
portsaid.gif - Masabb Dumyat to Port Said
suez.gif - Suez canal
gulfsuez.gif - Gulf of Suez with charted lighthouses
redsea1.gif - Red Sea, lat 28N to 25N
redsea2.gif - Red Sea, lat 25N to 22N
redsea3.gif - Red Sea, lat 22N to 19N,
Port Sudan and Jeddah
redsea4.gif - Red Sea, lat 19N to 16N
redsea5.gif - Red Sea, lat 16N to 13N
redsea6.gif - Bab el-Mandeb Strait
aden.gif - approach to Aden harbor
These are minimal charts with not much more than a coast outline and
a lat-long grid. They are all derived from the Map Viewer program at Xerox
PARC, http://pubweb.parc.xerox.map, with place names from assorted atlases
and encyclopedias. I don't have any access to the detailed information
usually found in navigation charts and these might better be called
"chartlettes". They are still usefull for providing some geographic
orientation for the Silicon Sea cruise and if printed can be used as
plotting sheets.
For plotting you will need a course plotter or some device for
measuring angles. Each chart has part of the latitude scale graduated for
measuring distance. You need to construct a scale for measuring longitude
but this is easy to do using the method outlined in Bowditch in the
emergency navigation section. You can probably get an accuracy of about 2
nautical miles.
There is also a Windows program to generate and print position
plotting sheets, posplot.zip at ftp://ftp.ronin.com/incoming. These sheets
include a compass rose and are specific for each latitude. Even with the
occasional jagged line of computer graphics they should allow an accuracy
equivalent to universal plotting sheets.
Let me know if you have trouble retrieving any of this.
Wes Murfin email: wmurfin@XXX.XXX
1409 Cando Pl phone: 910-455-8746
Jacksonville, NC 28540
