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Subject: Re: The mil as a unit of angle.
From: Brooke Clarke (brooke@XXX.XXX)
Date: Tue Mar 11 2003 - 20:40:41 EST
Oops,
That should have been 1 yard in 1,000 yards is approximately a mil.
Brooke Clarke, N6GCE
George Huxtable wrote:
> Dour Royer said-
>
> The use of a mil-compass is also needed.Mil does not
> >> stand for military but mil:1,000th of something.The mil-compass is hand
> >> held and has 6,400 seperate & equal segments in 360*.The compasses are
> >> also known as lensatic compasses.You can get great accurecy in
> >> distance,height and position useing the mil.
>
> Response from George-
>
> It's good that we keep on learning new things on this list. I had never
> heard of the mil as a unit of angle, nor had I come across insertion and
> resection in Doug's context.
>
> However, it's rather mind-boggling to discover yet another unit of angle,
> 64,000 in one rotation! Presumably, this is to put compass "points" at
> round-numbers of units. However, this convention shares many of the
> awkwardnesses of our 360 degree system. It makes the heart sink, when
> there's an obvious logical measure of angle just waiting to be adopted, the
> Turn, to be subdivided into 1,000 milliTurns. When you go through one Turn
> you get exactly back to where you started, so calculations involving angles
> exceeding 1 Turn just require dropping the integer part. It's decimal all
> the way, none of these nasty sexagesimals. Of course, it shares with all
> other decimal units the disadvantage of not dividing easily into 8ths and
> 16ths and so on, as were used for compass "points". But we don't use
> compass points much these days, courses and bearings are nowadays
> understood simply as a number.
>
> Of course, there are serious snags about making such a change. It would
> require recalibration of all our charts, compasses, and sextants. Not for
> the faint-hearted!
>
> George Huxtable.
>
> ================================================================
> contact George Huxtable by email at george@XXX.XXX by phone at
> 01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
> Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
> ================================================================
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