XXIV. J. IIAYDON CARDEW. 



Places has compiled a large amount of useful data respect- 

 ing our resources in underground water, but in perusing 

 the reports of some of the observers referred to we find 

 complaint of the lack of reliable data and indirectly a plea 

 for what the author advocates in order to make the reports 

 more complete and definite. 



The Government Astronomer says, in his Rain and River 

 Report of 1895, "In attempting to measure the quantity 

 of rainfall which the Darling carries off we are still met 

 with the want of necessary data as to the velocity of the 

 current and the area of the river channel." Again in 

 speaking of the estimates of the water passing down the 

 western rivers, he says, " Before accuracy can be obtained 

 detailed surveys are absolutely necessary, also daily records 

 of the velocity of the current." He repeats this in his 

 1899 report and adds the following significant statement, 

 44 At present we have only old sections of the river and an 

 approximate velocity of current, and I assume that the 

 Murray catchment in Victoria receives the same quantity 

 of rain as that in New South Wales, and that the Queens- 

 land portion of the Darling catchment receives the same 

 quantity of rain as that in New South Wales." Again in 

 his last published report of 1899, he says in referring to 

 the discharge of the Darling, "In the absence of a river 

 section at the weir it is impossible to estimate the percen- 

 tage of rainfall which passes Bourke." Also in pointing 

 out the effect of altitude upon rainfall, which he states is 

 a very material factor in the quantity received, he says, 

 44 for the great majority of stations this (the elevation) is 

 an unknown quantity," and in another place, 4 'I am fully 

 convinced that a complete record of the rainfall will enable 

 us to forecast the seasons with some show of success." 

 Nothing could be stronger than the foregoing evidence as 

 shewing the necessity and importance of a systematic and 

 comprehensive study of hydrography. 



