48 On the Supply of Water 



The first, or forty feet contour level, is about half the 

 annual rain-fall, and which would be equivalent to two and 

 a half years' consumption of double the present population, 

 at the Melbourne standard modicum of twenty-five gallons 

 per diem. Even after taking into account the probable maxi- 

 mum waste arising from absorption, decomposition, leakage, 

 and evaporation, on the one hand, and of no rain-fall what- 

 ever for the above period on the other. 



This, be it remembered, is without taking into account any 

 portion of the evaporation returned to the reservoir during 

 the two and a half years' assumed drought in the shape of 

 dew precipitated on the surface of the quiescent waters of the 

 reservoir, which of itself alone would yield nearly another 

 month's supply, exclusive of the ten feet depth of subsiding 

 space at a lower level, left untouched. 



In the absence of all meteorological observations to be 

 depended on, in times past, for this locality, I must per force 

 draw my conclusions from facts founded on those of the nearest 

 adjoining districts where a known careful register of the 

 quantities of rain falling has been kept for a series of years, 

 as indicated by the pluviameter. I grant, however, it is 

 difficult to calculate the rain-fall in any given district, even 

 to an approximation by data resting on observations taken 

 elsewhere ; yet, at the same time, in the absence of such 

 valuable and necessary local information, I must say that, in 

 proper hands, the former will approximate nearer the truth 

 than by quoting authorities from another hemisphere, it 

 being exceedingly doubtful, in the present state of meteoro- 

 logical science in the colony, how far it would be safe to rely 

 on such analogy, besides affording no guide in estimating the 

 proportion of rain-fall in so favorably circumstanced a locality 

 as that of Wormbete Forest. Besides, I prefer dealing with 

 facts, when to be had ; and, whilst on this subject, I will here 

 record one, not generally known either in the colony or 

 the mother country — a fact regarding the great amount of 

 difference existing between the rain-fall of Melbourne and 

 that of London, and several other cities of Europe. (See 

 Table No. V.) 



The synopses of several of the places enumerated are com- 

 piled from authentic documents kindly forwarded to me by 

 order of His Excellency Sir William Thomas Dennison, 

 Governor-General of the Australian Colonies ; also from W. 

 H. Freeling, Esq., Capt. R.E. ; Surveyor-General of South 

 Australia ; and the Corporate body of Launceston, Tasma- 

 nia ; A. J. Skene, Esq., District Surveyor of Geelong ; to 



