Algorithm used to convert coordinates from 1:250,000 miles map to metric AGD66 or GDA94 1:25,000 map

	// The coordinates of a matching point on the old map and new maps used for the conversion process
	double dOldMapOriginE = 438650.0; // Old easting in yards
	double dOldMapOriginN = 878000.0; // Old northing in yards
	double dNewMapOriginE = (m_nOutputDatum==0) ? 348995.0  : 349100.0;  // New easting in AGD66 or GDA94
	double dNewMapOriginN = (m_nOutputDatum==0) ? 6308260.0 : 6308450.0; // New northing in AGD66 or GDA94
	double dYardsToMetres = 1.0/1.09361;

	// Convert the old map coordinates in yards to the new map coordinates in metres
	m_dNewEasting  = dNewMapOriginE + (m_dOldEasting-dOldMapOriginE)*dYardsToMetres;
	m_dNewNorthing = dNewMapOriginN + (m_dOldNorthing-dOldMapOriginN)*dYardsToMetres;