Previously for about three years,  Brian and Fred, a Science and a Medicine undergraduate at the University of Sydney, had discovered and mapped many unexplored caves around New South Wales, most often under the beautiful white snow-gum tall trees of the Yarrangobilly plateau. They set and held world record concentration of "foul air" excessive concentrations of carbon dioxide to provide Professor Coffee with medical data he needed in research into safety of high-altitude balloon expeditions. 

We were assured by Professor Cotton via Denis Burke that in laboratory experiments you could easily survive concentrations of 20 to 30 per cent of carbon dioxide.  We were referred to a book by Smith and Fiddes “Forensic Medicine” 9th Edition, 1949, which on page 282 assured us:

 “Air containing 20% CO2 can be breathed with no noticeable effects.  When the concentration reaches 40% interference with the oxygen supply causes dyspnoea [difficulty in breathing], discomfort and muscular weakness. If there is any considerable excess of CO2, eg 60-80%, there may be immediate unconsciousness with or without convulsions and death occur rapidly unless the victim is removed at once.”

 I would add  now my comment and Fred's, "That book is wrong."

With Dennis Bourke and Ben Nurse, they pioneered in very, very primitive high-risk underwater exploration in caves before scuba gear was available in Australia. But at Yarrangobilly this time, Brian was as alone as anyone can ever be. In a talk to the Australian Speleological Foundation 50 years years later,(see O'Brien, 2003 in Publications) Brian said:

"There is an infinite difference between being lost yet being comforted by knowing for certain that people are searching for you, and being lost not knowing.

In the first you can have Hope in others. You are not really lost, just temporarily misplaced.

 In the second, you have only yourself and what you are.

You have only yourself and your memories. Fortunately, I knew a fair amount of poetry, and books I had already read, whose fragments in memory saved my sanity. In the cave the essential truth I found was that ultimately each individual is absolutely alone. I was as alone as is possible to be on this planet because I did not know if anyone was searching for me."

Brian, in the absolute silence of the cave, focussed in listening for a caller to answer Brian shouts in a series of 4 or 5 with minutes between, every hour or so, Cooee or BIK. He  also listened for a soft whisper of the underground creek that had made the cave, which in flood could bring down a fall in the roof whose jumbled rocks surrounded him.

He held his breath, so the only sound was his heart-beat of “whoosp, whoosp”.  He kept the bogeyman away by memories of beloved poetry and books. This first epiphany removed any of his fear of his death. It made him also very intrigued in risk management issues of many varieties in many fi elds, including strategic analyses.

Colour photos taken by Deborah Johnston of SUSS at East Deep Creek.

It was possibly his Yarrangobilly experiences that caused or matured Brian to be such a determined and long-term pursuer of the facts and the truths in his science career. His cultures insisting on Total Systems Analyses are clearly the resulting enveloping experimental methodologies.

His Injun 1 satellite in 1961 was one outcome, by his determination to know immediately the actual time the measurements were made, thus giving him the exact location in space. And so he fixed a time counter irrevocably to his stream of data by the first use of digital telemetry in a satellite. Also he guessed that the sharp digital telemetry would cut through noises bedevilling analogue signals.

In 1966, for Apollo and the ALSEP experiments, Brian thought it bloody stupid for NASA Manned Spacecraft Center (MSC) engineers and managers and myriad engineers of two aerospace companies to insist he put a dust cover on his CPLEE thereby increasing its risks, without requiring also a dust detector to measure the hypothetical problem dust. The others argued against any dust detector because (i) nobody had a very lightweight dust detector and, (ii) most important, they must not require any precious astronaut time. At the time, neither the USSR Lunar 9 nor the US Surveyor 1 had made the first photographs on lunar soil, so any arguments were ignorant about details of dust sizes.

So Brian invented the same night (12 January 1966) the DDE which was deployed by Apollo 11, 12, 14 and 15. Brian attributes the DDE invention to his frontal lobe doing its homework, once he had primed it with informed anger then relaxed before dinner. His frontal lobe, he suggests, remembered that 5 years earlier he had used solar cells to cool the temperature of his beloved Injun1 satellite. That trick had been superbly successful by accident, when Injun 1 solar cells survived the intense radiation from thermonuclear device Starfish but 8 other satellites had died prematurely. The DDE simply combined the vital jobs - his DDE is the only Apollo experiment to measure both cause (change in dust coating of a solar cell) and effect (change in temperature of the solar cell). The Total System for each DDE and the total system for each ALSEP. One further detail was that because nobody knew about sizes of individual dust particles, Brian's DDE simply measured all dust particles. Whereas previous dust detectors, and many later ones, measured momentum of individual dust particles one by one, the DDE measured the effects of billions to trillions of dust particles collectively, because they would be the cause of any overheating of ALSP components on the Moon.

Similarly, Brian applied Total Systems Analyses in only the second of  his 21st century conferences on lunar science, when he reviewed all three Apollo dust detectors, two of which were not mentioned in the widely-respected review by Colwell et al in 2007. As a result, he published O'Brien 2011 Review and discussed the likelihood that the forthcoming lunar orbiter LADEE would not measure the fine levitated dust that was its major objective. In that review, he drew attention to Tommy Gold's discovery, forgotten for 40 years, of cohesive forces of lunar dust. He also reviewed the popular interpretation for about 30 years that the unexpected electronic events registered by the Apollo 17 Lunar Ejector and Meteoroids Experiment (LEAM) were caused by a previously undiscovered species of levitated dust. Instead, he suggested the events were caused by electromagnetic noise in the Apollo 17 system.  

Three years after his Yarrangobilly adventure, Brian was elected first President of the Australian Speleological Federation. He challenged various speleological teams to find his carbide lamp where he had hung it before his fall over an overhang of a 12-foot cliff. He looked for the lamp on various return trips., including one with Avril,  before they were formally engaged.

The East Deep Creek cave has been locked against anybody except authorised speleologists. It has been mapped several times. The glorious tall coloured crystalline structures that enticed Brian to be the first to see them have been photographed many times. In 2016, a team involved in previous mapping became lost for some time, but found their own way out.

Colour photos taken by Deborah Johnston of SUSS at East Deep Creek.

We were assured by Professor Cotton via Denis Burke that in laboratory experiments you could easily survive concentrations of 20 to 30 per cent of carbon dioxide.  We were referred to a book by Smith and Fiddes “Forensic Medicine” 9th Edition, 1949, which on page 282 assured us:

 “Air containing 20% CO2 can be breathed with no noticeable effects.  When the concentration reaches 40% interference with the oxygen supply causes dyspnoea [difficulty in breathing], discomfort and muscular weakness. If there is any considerable excess of CO2, eg 60-80%, there may be immediate unconsciousness with or without convulsions and death occur rapidly unless the victim is removed at once.”

 I would add  now my comment and Fred's, "That book is wrong."