Flashing its Brilliant Rays!
Candlelight
As visitors marvel their way through Jenolan’s underground wonders, they point to a little box of candles, strategically placed next to the path, and ask, “You don’t still use candles do you?”
The answer, strange as it as it may seem, is “yes”. The humble candle, whose fitful spluttering light first lit the stygian gloom of the Caves, can still be called into action today. Should the most modern lighting system in the cave world fail, out come the candles to provide enough reassuring light until, in a matter of minutes, a huge diesel powered electrical generator comes on.
Of course today, the emergency flames of candles can be augmented by mobile phones. But it’s a curious thing that something centuries old, there at the very beginning of European visitation to the Caves, still plays a vital role today.
Yet the candle, which the first intrepid cave explorers easily carried, with spares and plenty of matches, has distinct disadvantages. A strong breeze can blow out the flame. Wax can drip on clothes and crystal features. Worst of all a candle and matches could be dropped into a pool of water. The result – disorientation and despair in the total darkness. This happened to the famed Jeremiah Wilson, the 'Crown Prince of Guides'. Visit the spot where this happened in the Jubilee Cave, and realize why it’s aptly called ‘Wilson’s Despair’.
The earliest visitors would stoop and sometimes crawl through narrow gaps, clutching their precious candle. One said,“Great care should be taken about candles as owing to the lack of space it would be very easy to set oneself on fire and very difficult after to extinguish” (J.J. Foster 1890)
Jeremiah Wilson made special candle holders that had a saucer shaped receptacle to catch the dripping wax. A spring loaded shaft pushed the melting candle up through the burn hole, ensuring that the flame continued to burn.
Magnesium Lamps
An improvement was the magnesium wire lamp, which used a clockwork mechanism to wind the burning wire off a drum into a large reflector dish. Then, cave features could be individually illuminated to everyone’s satisfaction. In 1887, an innovation that was remarked on was the ‘electric searchlight of 120 candle power’. "Carried through the Imperial Cave, it can be connected to all the important points, brings out every detail of the marvelous formations and fully puts the magnesium lamp in the shade." (SMH 17/2/1887)
In our Guides Office you can see a photograph of guiding staff, taken early in the 20th century, showing them holding both the electric searchlight light and candle holders, with the magnesium lamps at their feet.
First Cave in the World to have Electric Lighting
In November 1879, Thomas Edison patented his new invention, the vacuum light bulb with carbon filament. Less than a
year later, in July 1880, on the other side of the world, Lieutenant Colonel E.C. Cracknell,
Superintendent of Telegraphs, conducted an experiment in what is now the Chifley Cave, then known as the Left Imperial Cave. A firm believer in electric light and president of the Electric Society of Sydney, Cracknell had already demonstrated the power of electric illumination by mounting a searchlight on top of the General Post Office tower. The light was seen not only from the Blue Mountains, but out at sea!
A cave environment, with its hitherto impenetrable gloom, would provide the perfect setting to show what electric light could do. The chamber, at the top of the present day stairs to the Chifley Cave, was chosen because it had the most concentrated profusion of crystal features in the smallest area of the caves discovered up till then. The 40 yard (18 metre) climb involved dragging 18 zinc and cast iron Maynooth or Callan cell batteries, up to the cave.
“Each set of six cells weighed 96 pounds, the whole together with the acids and the generating apparatus exceeding 15 hundredweight” (Sydney Morning Herald 14/9/1880)
The equipment was manhandled up dry, and filled with charging acid in the chamber. This was no real obstacle to Cracknell and his assistants Ludovico Hart and a young man named Carruthers, for they were going to show the way of the future. Not so futuristic were the fumes given off, as as the batteries charged. The toxic cloud caused Cracknell and company to flee the chamber! The results were photographed by Hart and shown at the Melbourne Exhibition later that year.
You can still see an indication of the kind of lighting that Cracknell and Hart produced in that first chamber (called the Margarita Cave after Cracknell’s wife). The solitary bulb still used today, with a carbon element, dates from around 1920. This light would be augmented by a magnesium lamp. As the power supply improved, a hand-held electric lamp could trained onto a cave feature.
Everyone was so impressed by Cracknell’s experiment, that it was decided to light the Left Imperial Cave and the cave below it, the Right Imperial, with electricity. This was completed by 1887. The Lucas Cave, because of its immense size, presented particular problems and was left until 1893. Cracknell was the supervising engineer on the project and work began in 1884.
“ Arrangements are now being made in connection with the Superintendent of Telegraphs for the lighting of the caves by electricity, which will not only enable the natural beauties of the caves to be seen to greater advantage, but will also prevent them from being discoloured by the smoke from the numerous candles that now have to be used. It is proposed to utilize the waterfall in the creek close to the caves as the means of providing the motive power for the electrical apparatus” (Mines Department Report 1884).*
The waterfall referred to appears to be the one directly above the swimming hole downstream from today’s Blue lake.
An Interesting Curio
‘A interesting curio is the use of coloured lights. In 1890, the Sydney Morning Herald quoted photographer Ludovico Hart as saying “ It would be very difficult to find language that would adequately render justice to this fairy spot as we 
beheld it but to convey the faintest notion of what the scene was like when lit up by the light is quite impossible, more particularly when different coloured glasses rendered the walls and stalactites red, blue , yellow ect” (SMH 1/1/1890).
Coloured lights were used to illuminate the Devil’s Coach House Cave for the visit of the Earl of Jersey , Governor of New South Wales, in January 1893, and the tradition was carried on for many years. There was even a “Coloured Waterfall” feature in the Dragon’s Throat of the Temple of Baal Cave. Now, the only areas lit in colour are in the Bone Cave of the Lucas and the Architect’s Studio in the Chifley Cave. In both cases, we have made extensive use of the latest advancements in coloured lights. The coloured lights are fondly remembered by some older visitors, but derided by those who seek a more naturalistic cave setting.
Steam Power Generator
Initially Cracknell’s hydro power scheme was not employed. A substitute was a steam driven generator in the Grand Arch, fed by a plentiful supply of cut timber. Because of its limited generating capacity, banks of 10 lights could be turned on at any one time, and they were liable to dim, due to the fluctuations in power supply.
The steam driven generator is no longer there. But if you would like to see where it was located, look out for a grid in the stream on your right facing away from Caves House, then a water tap next to the pathway. Opposite is where the apparatus stood, and you might spot two small insulators above the road way. This marks the site of the boiler. A concrete ledge on the rock above was built to protect the generating apparatus from rainfall, situated three metres on the roadway towards Caves House. A line of insulators that carried that first power supply can still be seen, high up on the walls of the Grand Arch. The wires led into the Left Imperial Cave, through an area called The Shambles, then down into the Right Imperial Cave, near where the jaw bone of a Tasmanian Devil is on display today.
In the Shawl Chamber of the Imperial Cave, you can see an indication of the difficulties faced when the first lighting was installed. Using a ladder, a hole had to be hand-drilled, high up in the rock wall, with a copper clip cemented in, to hold the cables - all by the light of a hand-held candle.
Still, it was a marvelous innovation! It would be another 20 years before Sydney had street lights, and most domestic dwellings remained lit by gas for many years to come. Even Bathurst Hospital, for example, did not gain electric light until 1924.
The Leffel Wheel - Australia's first hydro power
An article in the Sydney Morning Herald, 10 April 1886, described how Harrie Wood, Undersecretary for Mines (the Government body overseeing the Caves) and C.S. Wilkinson, Superintendent of Caves, measured the flow of water over the ‘Falls’ as “…..the motive power for the electric lighting apparatus which thus may be worked at very small cost”
Another innovation was that “….the water wheel will also pump water to the accommodation house; at present the water required for the house and the horses has to be carried in buckets by hand from the falls as all the creeks in the vanity are dry and the inconvenience is consequently felt”.
In 1888, funds finally became available to carry out the original scheme, albeit in a different location. A water-driven turbine was ordered from James Leffel and Co. in the USA. Commonly called the Leffel Wheel, this was the first example of hydro electric power being used to generate electricity in Australia. The Imperial River was dammed, where it flowed into a swampy area beyond the Grand Arch. Wrought iron pipes, 650 mm in diameter, took the water down 200 metres in a gradual descent, to the site of the Leffel Wheel. You can still see the remains of a section of this pipe in the Blue Lake, close to the pathway, on the roadway side. To spot this, walk along the pathway until you come to a large upturned tree, partially submerged in the water. Just after this is a lamp post, then a set of stairs with stainless steel handrails. Look down to the right and in the water is the Leffel Wheel feed pipe.
When the decision was made to light the Lucas Cave, additional capacity had to be sourced, to drive 6 proposed large arc lamps in the Cathedral Chamber. This was done by simply adding another dynamo, driven off the turbine by a layshaft and flat belt drive.
Hydro Electric Power Station
Although adequate for the existing caves, the discovery of the River Cave, the Temple of Baal Cave, Orient Cave and Pool of Cerberus Cave meant that further power was needed. The 1908 solution was to build another dam, considerably larger than the 1889 one. The turbine and its 2 generators were moved further down the valley, to create a greater head of water. The Jenolan Lake, now more commonly called the Blue Lake, was created.
With the expansion of Caves House to three stories in the middle of the First World War, the Leffel Wheel, having given 27 years faithful service, was decommissioned. The decommissioning was delayed because the ship carrying the new equipment from Britain was torpedoed by a German submarine. A new hydro electric power station was built, with 2 turbines and 2 generators, in their own power house, 900 metres downstream from the Grand Arch. The 20 kW generators were from the Westinghouse Company. The 2 Pelton wheel turbines were from James Gordon & Company. They were all turned on in 1916.
You can still see the remains of the Leffel Wheel, on the 'Working Waters' self-guided tour, below the Blue Lake dam. A sign gives a brief explanation of how it operated, as does the Acoustiguide audio commentary for this trail. The transmission towers, to carry power from the Hydro electric plant into the caves, still stand beside the lake, whilst high up in the Grand Arch is an inverter house that converted the generated current from 240v to 110v to light the caves. (110v was the preferred operating current of the Mines Department.)
The hydro plant was upgraded in 1953, with a back up diesel generator installed in the old coach house located above the lake.
Nowadays, electricity from the state grid powers the Caves and Cave house, while the hydro, using one of its generators, serves some staff cottages.
The original wiring in the caves used cloth covering, which rotted in the damp atmosphere. Knife blade power switches suffered similar problems with corrosion. A gradual program to replace all the wiring and switches was undertaken from the 1950’s onwards.
Most Advanced Cave Lighting System in the World
During the new century, with new technology, it was decided to relight the entire cave system. The Imperial Cave was the first to have the C–Bus system. This is a microprocessor based control and management operating system, triggered by remote control. Diochroic lights and compact fluorecscents (later LEDs) were installed in the caves, on the south side of the limestone belt.
The great advantage of the new system is that it operates at a much reduced voltage thus drawing much less power. The new lights give off very little heat. The old incandescent bulbs encouraged lampenflora (moss) to grow on the crystals. The Carbon footprint of Jenolan Caves, once the size of an elephant, is now the size of a small bird. Eventually all the caves will utilize this technology, which is currently considered the most advanced Cave lighting system in the world.