Hi all,
We are in Broken Hill and we will be home in about two weeks, but this email will show you excerpts from our trip down from Tennant Creek to Port Augusta.
Travelling from Darwin to Tennant Creek (990 km), we were retracing our northward journey, but after Tennant Creek we were in new territory.
The Devils Marbles is an amazing collection of rocks about 100 km south of Tennant Creek. It is a National Park, we camped there, it was very hot with very little shade. You can just see the edge of the campsite in the right edge of the picture.
This close-up shows rocks about 20 to 30 metres high. The colours change depending on time of day and direction of the sun and camera. This is late afternoon with the sun behind the camera. Alice Springs is another 400 km south. We are sitting in Studio 1 of ASSOA (read the logo) having a private internet lesson with Cameron, Lee's student 1,100 km away at Nutwood Downs. Cameron's teacher showed us around the school then offered to arrange the lesson. It was great. The studio has a big glass wall so tourists can see and hear the lessons. We were on display for a bus load of American tourists, who could also see and hear Cameron on their monitor.
The West Macdonnell Ranges are breathtaking. We camped at Ormiston Gorge, seen here looking up the canyon from a walking track. The large pool in this photo can be seen in the next one.
Here we are looking nearly in the opposite direction out the mouth of the gorge. The redness of the rock walls had to be seen to be believed.
If you get to Standley Chasm right on midday you can take a picture like this. The white floor of the chasm reflects the sun onto the walls, which are just on the edge of the sun's rays. The whole thing glows, but it lasts for less than an hour.
This Spinifex Pigeon was in the Alice Springs Desert Park, a botanic garden on the edge of Alice Springs. We spent a whole day there. 
We passed the Greyhound Bus several times as we travelled south (not the same bus). It goes every day from Adelaide to Darwin, 3000 km, in 43 1/2 hours, stopping for meals and to swap drivers four times. It stops for passengers and mail at every roadhouse and station mailbox on the way. The Station people depend on it. This was how people from Nutwood Downs got to Katherine, Darwin, etc. As we travelled south from Alice Springs we saw several wedgetail eagles. We stopped and I was able to get these close-ups before he flew away.
His wingspan is about 2.2 metres.
Another 680 km south of Alice Springs is Coober Pedy, the centre of Opal mining for the world, with over 90% of world opal production from this area.
There are no big mines, all claims are between one and four persons. The miners buy or lease large machines mounted on trucks, with a generator, a cutting machine and a huge blower, capable of throwing rocks the size of cricket balls (and larger) to the surface. hence the mounds. If they find the right strata, then they dig by hand so as to not destroy any opal. Dirt mounds like the above cover an area 30 km north and south of Coober Pedy.
The town has about 3,000 people but they are transient. About 60% live underground. There are three underground churches, this is the entrance to the Anglican. The rector's house is also underground, to the left. Look closely and you will see white poly pipes on the RHS of the hill above the church. These are for ventilation. All underground buildings have wet areas at the front and it is best if they slope slightly uphill.
This is the inside of the church. Surface conditions can be very hot and dusty. It is real desert. Underground the climate doesn't change much. The walls are sealed to avoid dust, and the texture and colour is very attractive, a pinkish texture. 
Just east of Coober Pedy is a section of the Dog (dingo) fence. It stretches 5,300 km through South Australia, NSW and Queensland. it aims to keep wild dogs on the north-western side away from grazing lands. You can also see the flat landscape and stony desert conditions of this area.
The southern part of our journey (south of Alice Springs) comprised mainly desert, the northern part was in the tropics so had more rain and vegetation.
This picture is looking directly at the sun as it sets, at Lake Hart, a salt lake between Coober Pedy and Woomera where we bush camped for the night. We didn't go into Woomera, it is off the main road. We reached Port Augusta the next evening. Port Augusta calls itself the crossroads of Australia, you can go north to Darwin, west to Perth or east to Sydney, Melbourne, Adelaide by road or rail. We had travelled 2,700 km almost due south from Darwin. The days had been very hot all that way. The weather changed at Port Augusta, we went from hot to cold in one night. . We were ready to turn east for home, planning to go via Broken Hill, Mildura, Wagga and then to Sydney.
Till then,
Goodbye and God Bless,
Peter and Lee.
