Subject: Re: [BoundaryPoint] 49th Parallel FunFacts<br/>
Date: Nov 26, 2001 @ 23:31<br/>
Author: Brendan Whyte (&quot;Brendan Whyte&quot; &lt;brwhyte@...&gt;)<br/>
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<div id="ygrps-yiv-877948136">Jones, &quot;Boundary-making&quot;, Carnegie endowment, 1945.<br/>
fig.24 on p154 maps pillars 46 to 58. The bundary is the &#39;mean astronomic <br/>
parallel&#39;. it does not coincide with the geodetically determined 49th due to <br/>
the effect of gravitational anomalies on the levelling of instruments.<br/>
If someone has a list of lats and longs for the pillars, why not convert the <br/>
dms to decimals, and plot them all in Excel as a graph. Then we can see how <br/>
sinusoidal the pillars are compared to the 49th itself.<br/>
Perhaps someone can develop a fourier series to describe the path of the <br/>
boundary joining the pillars which must be rather wave-like?<br/>
<br/>
BW<br/>
<br/>
<br/>
<blockquote><span title="ireply"> &gt;Any opinion as to why Monument 490 is as accurate as it is with respect to <br/>
&gt;latitude?  I assume that monumentation of the 49th is as varied as it is <br/>
&gt;due to the limitations of older astronomical surveys, etc.  Since &quot;once <br/>
&gt;it&#39;s marked, it&#39;s marked&quot; is the general rule, is fair to conclude that <br/>
&gt;#490 was surveyed much more recently than most of the other monuments?<br/>
&gt;<br/>
&gt;Bill<br/>
&gt;<br/>
<br/>
 </span></blockquote>_________________________________________________________________<br/>
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