Mornings are 3 deg C with a chilly wind.

Uninviting. We've been inside people rather than setting up table and chairs.

The Thuraya Sat Phone has been a bit iffy.

The satellite is low on the horizon from here. A lot of atmosphere between us and it.

A lot of dropouts and missed calls.

More frustrating has been the unreliability of sms. The phone says "sent successfully". Nothing received at the other end.

Looks like we were incredibly lucky to contact Paul in Melbourne to get spare axle sent.

To compound the problems the phone number to recharge through the phone only appeared on the web page I recharged with. I didn't write it down, and Chrome won't show it to me without internet connection ..... fortunately Jennifer to the rescue, she managed to recharge it for me. Sounds like it was a challenge. I'll get the story later.

This patch of desert is "less alive" than our last dune top in the west.

We are aware of how science has described the desert in regions but it is quite another thing to experience it.

We haven't seen a bird of prey all day. No dingos seen, though a few tracks.

The trees are different. The cane grass more sparse and lower.

We've had to be very observant to see beetles. Few and far between.

With two different droppings adjacent.

We can only imagine what caught it, and why it wasn't completely eaten.

Maybe in wetter times. We also saw evidence of a small kangaroo hopping along the next swale, when the ground was very damp.

We've only seen one track that looked like a passing snake.

Always changing.

This one had conveniently stopped for us.

At last the association between beetles and the tracks they make.

This pic has been a couple of weeks in the making.

Overnight, we are pondering whether there are small droppings (1/5th the size of rabbit) next to our steps. Or just seeds.

The pellets crumble to sand when squashed.

We'll have the torches ready tonight.

Overlooking a dry lake bed.

Our dune is a couple of hundred meters wide. Like a series of waves, narrower dunes, melded together.

We are camped just one rise short of the eastern side.

From the east we have a couple of flags atop the dune as warning.

We observe an interesting mix of vehicles, and equally interesting mix of driving techniques.

This is important as we ask what the track between us and Birdsville is like. So we can estimate how long the round trip will take. Its about 170 km one way. It depends who is telling us about it - typical of descriptions about anything.

At the other extreme are the "bull in a china shop rev the engine take a run at it drivers" who snake and bounce their way up the soft sand with a final mighty engine roar to get over the last little bit in a flurry of sand.

This leaves a series of "scallops" which causes the next vehicle to bounce even more and increase the depth some more.

The scallops are offset, as first one wheel then the other side spin more than the first side.

At times the moguls (for the skiers) are just the right distance apart that if not careful with speed our vehicle can turn into a pogo stick with all four springs engaged in synchronised bouncing.

The pic is of where someone's spinning wheel finally got traction at the top of a dune as the vehicle began its descent on the far side.

While some of the difference is vehicle power and weight dependent we conclude that most of it is differences in tyre pressure and driver technique.

Thus, the track descriptions vary from "this is the hardest one, they are easier from here" to "its tough".

A passing tag along leader seemed to have a well trained group and a credible track description.

We tend to soft tyres and constant speed. A speed/load/tyre pressure chart helps to limit speed so tyres don't overheat.

We think at least 10 hours to Birdsville.

Motor bikes are interesting for different reasons. The techniques and success rates vary but the experts make it look easy.

We've contemplated sitting atop the dune and offering scores out of 10 to each driver.

Around 30 vehicles per day.

The grapevine along the track is working well. Most seem aware of "two broken down vehicles".

We seem to be halfway between campsites that people leave in the mornings.

Towards the end of morning tea we became excited as first one, then another, bird landed on a nearby tree.

More black faced  wood swallows.

Text messages that never get anywhere. From either end.

Including ones sent to us from the sms.thuraya.com web page.

A fundamental flaw in their protocol, or congestion, methinks.

Frustrating as the phone says "sent successfully".

We must have been very lucky connecting with Paul (for new axle). I forgot to ask for a tracking number. Subsequent attempts to phone have ended with the sat phone simply not connecting.

Birdsville post office unfortunately has an answering machine. Hard to know what message to leave.

But we think we have a partial solution to signal strength and consistency .... the pic is during a phone call to daughter Jennifer - doing a brilliant job of understanding our position and helping with messages. And with a call to Birdsville post office.

The spare tyre was comfortable.

Finally, a flood of texts received. One with aus post tracking number from Paul, forwarded to Jen. One with another Peter - Oka - a couple of days behind us we hoped to meet up with. There is no sent date, only receive date time. One with "thanks for the money"! Another from Jen, a couple of days old, saying can't call us.

Obviously technology has expectations and a learning curve. Greatly assisted by sitting on the cab in a bizarre parody of semaphore - that's why the flag is the shape it is?

Now we know (thanks to Jen) that the axle has got as far as Toowoomba.

The mail truck for Birdsville leaves Copley each Tuesday. Reaching Birdsville on Friday.

We are hopeful that Australia Post has a more direct route from Toowoomba than via Copley.

We haven't heard a dingo for a few days. But see tracks along the dune tops.

Lizards and "mice" elude us.

This butterfly stopped for a moment in its endless meanderings.

We ponder what accidents of nature make this dune top so very different to our first dune top.

The colours are different each day.

A mixture of tyre,  wind, and foot tracks.

This is our third.

Graduation to lizards still evades us.

What more can we say.

A Landrover club, wisely separated as group of 9 and group of 7.

This was the oldest.

It went up the dunes just the same as the youngest.

Possibly something burrowing through the sand rather than walking over it.

Or even if it all happened at the same time.

The wind has dropped, almost still at times, and its warmer.

The tracks are sharper, and last longer, which gives the appearance of more.

We turn the heater on briefly each morning.

East and south from the campsite.

A strangely dense patch of gidgee.

We wonder if gidgee are what earlier travelers referred to as cork trees.

Life curtailed before it really started.

No trees near.

And we feel that the axle may just as well be on the moon as in the clutches of Australia Post.

We've only been here four nights.

Different to our previous dune top.

This time we have a pervading sense of waiting for something. Overtaken by events beyond our immediate control.

Previously we could enjoy the dune as long as we wanted to.

A subtle difference really. We can think of worse places to be and its what we came to see.

We heard a few crickets.

Seeing them is less frequent.

This is our first, and only, sighting.

The night air is still. We could see nothing moving apart from ourselves as we blundered around wreaking havoc with our torches.

We suspect our search technique requires substantial refinement.

Many have commented on the stillness of the desert.

Our little patch of the Simpson is as still, and as silent (if that is possible) as anywhere we have traveled.

We have become almost used to it.

Roughly sufficient for 10 days at current rate of consumption, with a bit of margin for error.

The ups and downs are mostly due to "who cooks tonight".

We normally don't have to watch our water this closely. We've had 5 years with no gauges. Knowing when tanks became empty and a rough indication of use was sufficient.

With the flow meter we get better feedback on how changes in our behaviour reduce usage. But really just a useful check.

Looks like heading to Birdsville when mail delivered or we reach 20 litres remaining. Whichever comes first. A roll of life's dice?

We are still in bed. The sun has risen. The first motorbike has passed. The heater is on. The hot water temperature is slowly increasing from its overnight low of 16 deg C. Air temperature rising faster from lower.

We think that today another Peter in another Oka will join us from the west.

Part of a planned trip into Allandale if permission has been granted.