David McDonald wrote:
>
> With the advent of the Birds Australia Alas, GPS receivers have become
> as important a piece of birding equipment as binoculars and field
> guides. Well, almost, anyway. Probably I am not the only person who
> finds it a pain to identify accurately my latitude and longitude from
> the AUSLIG 1:100,000 maps, the type I usually use, when I do not have
> my
> GPS receiver with me. Having used grid references on these maps (and
> the
> 1:63,360s before them) for most of my life I find the switch to
> lat/long
> a bit of a pain. (Yes, I have and sometimes use the Excel spreadsheet
> provided by AUSLIG for for converting between grid refs and lat/long,
> but it is all a bit tedious.)
>
> One thing intrugues me. With grid references we conventionally cite
> the
> easting followed by the northing. There is no choice in the matter.
> But
> with latitude/longitude we conventionally do it the other way round:
> nn
> degrees/minutes/second South (latitude) followed by nn
> degrees/minutes/seconds East (longitude). The GPS receivers' readouts
> also deal with them this way.
>
> Does anyone know how we came to have these differing sequences?
>
> David McDonald
>
Don't know how or when or why the grid and geographic inversion
occurred, but I remember feeling a preference for GRID when the first
atlas project was running; then I contemplated the 7? zones involved and
the fact that only those with copies of Australian maps would be able to
locate the sites whereas Lat/Long can be found in an atlas. And the
1:1,000,000 Aeronautical maps don't have the grids anyway.
We used to rule the Lat/Long grid on the maps before setting out on a
trip.
One of the favourite sports on trips run by the LandRover Owners Club of
Vic is to compare GPS readings at the lunch stops! And if the US
military is playing with the signals you can get VERY silly results.
Brian Fleming
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