1314 AUSTRALASIA ILLUSTRATED. 



its way to the ocean. The comparative abundance of rain on the east coast-range is 

 due to the situation of the high land with reference to the direction of the rain-bearing 

 winds, many of which come from the tropics and travel in an easterly or south-easterly 

 direction over Australia, and, as they rise over the mountains, are compelled to deposit 

 their moisture by the elevation they have to make in getting over. 



Up to the present time little or nothing has been done by the Colonial Governments 

 to conserve water, except for towns and stock, but abundant evidence has been collected 

 to show that so soon as the natural facilities for irrigation are made use of, the 

 colonies will be enormously enriched by a greatly extended agriculture ; for the western 

 slopes of the Main Range on the east coast, with their ample rain-fall and numerous 

 half-formed natural reservoirs, wait only the magic touch of the engineer to convert them 

 into valuable farm-lands. 



How far subterranean water may be available for irrigation and other purposes, is a 

 question that is being slowly answered in the various colonies by sinking wells, and the 

 answer, so far as it goes, is exceedingly encouraging. Very many wells yield an abun- 

 dant supply of artesian water ; the last finished at a depth of 1,073 feet, is in the 

 Bourke District, and yields 350,000 gallons per day. The study of the rain and river 

 statistics for the Darling River shows that it carries off less than one per cent, of the 

 rain-fall, taking the average over eight years, and that, therefore, there must be enormous 

 quantities of water passing through the porous strata into under-ground drains to feed 

 these artesian wells ; and measures of one of the rivers the Macquarie show that its 

 bed is porous in this way to a very unusual extent, and that it allows the water, which 

 finds its way into it from the hills, to sink rapidly down. The deepest well yet made is 

 near the centre of Australia, and is 1,220 feet deep. 



The simplest and least expensive system of conserving water has been in use for 

 years in large areas which have neither rivers nor other natural surface-water. This is 

 the construction of tanks, or artificial hollows, in places suitable to collect the rain-water 

 which runs off the surface, and experience shows that if these are made fifteen or twenty 

 feet deep, they will conserve sufficient water for cattle and sheep through the worst 

 drought, even when they are not covered in to prevent evaporation. 



In the existing water-courses and lakes are to be found abundant proof that at a 

 time long past the rain-fall was enormously greater than it is in the present day. At that 

 time, in all probability, the great east coast-range was- very much higher than it is now, 

 and was one of the causes of that greater rain-fall, but those very rains which it helped 

 to produce, gradually cut away its elevation by denudation, and destroyed its power of 

 rain-making, but rain-records do not go back to that extremely remote period when 

 rain was so abundant. Within the last twenty years, rain observers, encouraged by the 

 astronomers in the colonies, are springing up in all directions, and from their combined 

 labours we have statistics showing the rain-fall of the whole of the coast, except the 

 extreme north-west, and of a considerable portion of the interior, and we have the 

 records from a few places on the overland telegraph line in the very heart of Australia. 

 These records show that the average rain-fall of the colonies is as follows : South 

 Australia, 20 inches; Victoria, 32 inches; New South Wales, 25 inches; Queensland, 27 

 inches; Western Australia, 23 inches; a few observations taken at intervals in the central 



