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Index of Subjects --part1_297a7.7ef3e4fb.3d2cb3d0_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit A couple of thoughts as an ancient navigator. An Astrolabe measures altitude of a heavenly body and that is all it does. That means that it can be used measure Latitude when the sun is bearing North or South and you are armed with tables giving current declination. As far as local time is concerned, that is apparent noon but does not take into consideration time zones. To determine longitude, accurate time is needed and that wasn't possible until the chronometer was invented by a fellow Lincolnshire poacher. There was another way of determining longitude without time involving lunar observations but it was not within the expertise of most mariners. An appropriate issue the day after seafarers Sunday. Captain Peter Stow Hubbards In a message dated 09/07/2012 6:29:56 P.M. Atlantic Daylight Time, dwebster@glinx.com writes: Hi, July 9, 2012 I noticed on Wikipedia in the astrolabe article (line 4) a statement that appears to be incorrect; namely that an astrolabe can be used to determine "...local time given local latitude". In the above quote should latitude not be longitude ? Yt, Dave Webster, Kentville --part1_297a7.7ef3e4fb.3d2cb3d0_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content=3D"text/html; charset=3DUS-ASCII" http-equiv=3DContent-Type> <META name=3DGENERATOR content=3D"MSHTML 9.00.8112.16446"></HEAD> <BODY style=3D"FONT-FAMILY: Arial; COLOR: #000000; FONT-SIZE: 14pt" id=3Dro= le_body=20 bottomMargin=3D7 leftMargin=3D7 rightMargin=3D7 topMargin=3D7><FONT id=3Dro= le_document=20 color=3D#000000 size=3D4 face=3DArial> <DIV><FONT size=3D4>A couple of thoughts as an ancient navigator. An Astrol= abe=20 measures altitude of a heavenly body and that is all it does. That means th= at it=20 can be used measure Latitude when the sun is bearing North or South and you= are=20 armed with tables giving current declination. As far as local time is conce= rned,=20 that is apparent noon but does not take into consideration time zones. To= =20 determine longitude, accurate time is needed and that wasn't possible = until=20 the chronometer was invented by a fellow Lincolnshire poacher. There was an= other=20 way of determining longitude without time involving lunar observations but = it=20 was not within the expertise of most mariners. </FONT></DIV> <DIV><FONT size=3D4>An appropriate issue the day after seafarers=20 Sunday.</FONT></DIV> <DIV><FONT size=3D4></FONT> </DIV> <DIV><FONT size=3D4>Captain Peter Stow </FONT></DIV> <DIV><FONT size=3D4>Hubbards</FONT></DIV> <DIV> </DIV> <DIV> <DIV>In a message dated 09/07/2012 6:29:56 P.M. Atlantic Daylight Time,=20 dwebster@glinx.com writes:</DIV> <BLOCKQUOTE=20 style=3D"BORDER-LEFT: blue 2px solid; PADDING-LEFT: 5px; MARGIN-LEFT: 5px">= <FONT=20 style=3D"BACKGROUND-COLOR: transparent" color=3D#000000 size=3D2=20 face=3DArial>Hi, &= nbsp;=20 July 9, 2012<BR> I noticed on=20 Wikipedia in the astrolabe article (line 4) a statement <BR>that appears = to be=20 incorrect; namely that an astrolabe can be used to <BR>determine "...loca= l=20 time given local latitude".<BR><BR> In the above quote shoul= d=20 latitude not be longitude ?<BR><BR>Yt, Dave Webster, Kentville=20 <BR><BR></FONT></BLOCKQUOTE></DIV></FONT></BODY></HTML> --part1_297a7.7ef3e4fb.3d2cb3d0_boundary--
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