Spinifex and Sand/Part III/Chapter II

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12289Spinifex and Sand — Part III, Chapter IIDavid Carnegie

Part III: Second Prospecting Expedition

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Chapter II: Granite Rocks, "Namma Holes", and "Soaks"

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At this point it may not be amiss to give a short description of these peculiar outcrops of granite, without which the track from York to Coolgardie could never have been kept open, nor the place discovered, nor could its early inhabitants have supported life before the condensing plant came into general use.

The interior of the Colony, between the coast and a point some hundred miles east of Coolgardie, is traversed by parallel belts of granite, running in a general direction of north-north-west and south-south-east. This granite crops out above the surface, at intervals of from ten to twenty or thirty miles, sometimes in the form of an isolated barren rock, and sometimes as low ranges and hills several miles in extent. From them small creeks, and sometimes larger watercourses, run down, to find their way into the stony and gravelly debris which usually surrounds the rocks. Much of what little rain does fall is absorbed by the trees and scrub, and much is taken by the sun's heat, so that a very small proportion can sink below the surface soil, and only when there is some underground basin in the rock beneath will water be found by sinking, except immediately after rain.

Round the granite base a belt of grass of no great extent may be found, for the most part dry and yellow, but in places green and fresh. It is in such spots as these that one may hope to tap an underground reservoir in the rock. To these shallow wells has been given the name of "Soaks." They seldom exceed fifteen feet in depth, though similar subterranean basins have been tapped by a well perhaps a hundred feet deep, sunk some distance from the foot of the outcrop. A good soak will stand a heavy drain for perhaps months, but not having its origin in a spring the supply ultimately ceases.

The soil, being alluvial, is in most cases easy to dig, and when the bed rock is reached it becomes an open question whether to go deeper into the decomposed rock or to be content with what supply has been struck. Many a good soak has been ruined by a too ambitious worker, who, after infinite toil, may see his priceless fluid disappear down some hidden crack beneath. Native soaks dug out with sticks and wooden "coolimans" — small troughs used as spades or as a means of carrying seeds, water, or game — are by no means uncommon, and, when holding water, are easily made more serviceable by throwing out a few shovelsful of sticks, stones, and sand, with which they are generally choked. Often the weary traveller has no such lucky help, and must set to work to dig a soak for himself and his thirsty beasts — against time, too, in a blazing sun, without the comforting knowledge that there is any certainty of finding water. I do not know of any case when a party has actually perished at the mouth of a waterless soak, but in many instances water has been struck when all hope had been given up. The skeletons and carcasses of camels and horses tell a tale of suffering that no man who has travelled can look at unmoved, and go to show that many a beast of burden has been less fortunate than his masters.

With what eager anxiety the shovelsful are watched, when the expected "bottom" is nearly reached, by man and beast alike, who, utterly weary and absolutely parched, know that they are soon to learn their fate. The horses snort and plunge in eager and impatient expectation, whilst the patient camel contents himself with grunts and moans, though, as his knees are probably strapped beneath him, he cannot protest more forcibly. At length, perhaps, all are rewarded by the welcome sight of a tiny trickle in one corner, or perhaps the hole turns out a "duffer," and the weary, weary work must be commenced again in a fresh spot.

In many cases these granite rocks have been utilised as a catchment area for tanks, into which the water is led by drains, which encircle the foot of the outcrop. Before the railway was built, such tanks, sunk by Government along the Southern Cross-Coolgardie track, enabled teamsters to bring their horses through with safety, which would otherwise have been impossible at some seasons of the year.

I append a table showing cost and contents of Government tanks excavated at the base of granite rocks between Southern Cross and Coolgardie: —

Name of Reservoir. Cost Contents in Gallons Cost per Million Gallons (pounds).
Reen's Soak £3,246 900,000 3,607
Kararawalgee 2,947 1,250,000 2,858
Boorabbin 3,025 900,000 3,461
Woolgangee 3,825 1,2501000 3,100
Bullabulling 4,118 1,250,000 3,294
Coolgardie (No, 1) 1,167 800,000 1,454
Coolgardie (No. 2) 2,110 1,400,000 1,503
Halgoorlie (half-way) 1,266 500,000 2,532
Kalgoorlie... 1,554 500,000 3,108
Twenty-five Mile Tank 1,881 500,000 3,762
Forty Mile Tank 1,546 500,000 3,092
Colreavy's Tank 2,193 997,000 2,199

The above table will give some idea of the enormous expense entailed by the opening up of the interior. In addition to these, wells and bores were put down, many of which failed to strike water.

Ever-thoughtful Nature has provided, on the surface of the "granites," small reservoirs which, after rain, may, in some cases, hold many hundred gallons of water. The Rock — or Namma-holes (I presume "Namma" is a native name, but of this I am uncertain) are usually more or less conical in shape, and vary in depth from a few inches to twenty feet, and in diameter from half a foot to several. Their sides are smooth, and slope down to a rounded bottom, where stones are often found which would suggest that they have had something to do with the formation of these peculiar holes. Beneath a hard surface layer the rock becomes decomposed and comparatively soft; and doubtless the rain of countless ages collecting round the stones, once on the surface and now found at the bottom of the holes, has at length weathered away the rock, and so by slow degrees the stone has ground out an ever-increasing hollow. I am neither geologist nor dentist, but I have often likened in my mind the formation of the Namma-holes to the gradual hollow formed by decay in a tooth. Whatever their history, their use is unquestionable — not so the flavour of their contents; for every bird or beast coming to water will leave some traces behind, and the natives, to prevent evaporation, throw in sticks, stones, and grass. Such a collection of rubbish and filth might naturally be supposed to render the water unhealthy, but apparently this is not the case, for we have often been forced to drink water, which, in civilisation would be thought only fit to be used as manure for the garden, without any injury to health or digestion. Patient search over the whole surface of the rock is the usual method for finding rock-holes, though sometimes the pads of wallabies, kangaroos, or emus, may serve as a guide to them, but game is so scarce that a man must usually trust to his own observation. Sometimes their existence may be detected from a distance by the patch of rock round the mouth showing white, owing to its being worn by the feet of birds and animals.

A typical rock was the high, barren "Cowarna," and one that after rain would store in its depressions a plentiful supply of the life-giving water. Thankful for small mercies, I made the best of a bad job, and, having no dish or bucket from which to give Satan a drink, I was obliged to make him lie down close to the narrow hole, whilst into his willing throat I poured the water which at arm's length I scooped up with my quart pot. This tedious process finished, I still had a potful at my disposal, so, taking a long drink myself, I stripped off my clothes and indulged in a shower bath, Not a luxurious bathe certainly, and a larger supply would have been acceptable, but every little helps, and even a few drops of fresh water have a pleasant effect on one's body made sticky by the salt of the water from the lakes, and serve to remind the traveller that he has once been clean.

Condensing water on a salt lake

Leaving the rock at sundown I travelled well into the night, for progress was slow through the scrub and trees in the darkness, but little relieved by the light of a waning moon. Feeling sure that I had gone far enough, I was preparing to rest awhile and find our camp in the morning, when the welcome glow of a fire shot up through the branches. Jim and Paddy, with characteristic thought and resource, had climbed to the top of two tall and dead gum trees and there built fires, fanned by the fierce draught through the hollow trunks, knowing well at what a short distance a fire on the ground is visible in this flat country. During my absence they had found no gold, but, as they liked the look of the country, we decided to return to our condensers for a fresh supply of water. Having obtained this, Egan and I revisited our previous prospecting ground, leaving Jim behind to "cook" water against our return; and a more uninteresting occupation I cannot well picture. Camped alone on a spit of sand, surrounded by a flat expanse of mud, broiled by the sun, half blinded by the glare of the salt, with no shade but a blanket thrown over a rough screen of branches, and nothing to do but to stoke up the fires, change the water in the cooling-trough, and blow off the salt from the bottom of the boilers, he was hardly to be envied. Yet Jim cheerfully undertook the job and greeted us on our return, after four days, with the smiling remark that his work had been varied by the necessity of plugging up the bottom of one of the boilers which had burned through, with a compound (a patent of his own) formed from strips of his shirt soaked in a stiff paste of flour. That night we were astonished by the passage of a flight of ducks over our heads, which Egan saw, and I and Conley heard distinctly.

A detailed account of our wanderings would be as wearying to the reader as they were to ourselves, a mere monotonous repetition of cooking water and hunting for "colours" which we never found. Christmas Eve, 1894, saw us in the vicinity of Mount Monger, where a few men were working on an alluvial patch and getting a little gold. A lucky storm had filled a deep clay-hole on the flat running north-west from the hills, and here we were at last enabled to give the camels a cheap drink; for over six weeks we had not seen a drop of fresh water beyond what, with infinite labour, we had condensed, with the one exception of the small rock-hole I found at Cowarna. My entry in my journal for Christmas Day is short and sweet: "Xmas Day, 1894. Wash clothes. Write diary. Plot course." We had no Christmas fare to make our hearts glad and but for the fortunate arrival of my old friend David Wilson, who gave us a couple of packets of cornflour, would have had a scanty feast indeed.

Even in the remote little mining camp Santa Claus did not forget us, and spread his presents, in the form of a deluge of rain, on all alike. What a pleasant change to get thoroughly wet through! The storm hardly lasted twenty minutes, but such was its violence that every little creek and watercourse was soon running, and water for weeks to come was secured and plentiful in all directions; but so local is a summer storm that five miles from the camp, no water or signs of rain were to be seen. Our provisions being finished, nothing remained but to make all speed for Coolgardie, some fifty miles distant by road. Unencumbered by the condensers, which were abandoned as useless since the bottom of both boilers had burned through, we made fair time, reaching a good camping-ground two miles from the town on the evening of the second day, the 30th of December.