gauge, wo ii If, surely he just died when its importance in com- 

 parison with other Meteorological Stations is considered. 



The sheets taken from the barrel of this instrument were 

 regularly sent to the Observatory at Sy.lm -y, where they 

 have been filed for reference. With the help of these 

 records from 1885 to 1907, and the previous information 

 supplied hy Mr. Russell, I completed his diagram and have 

 shown it on mine in full black. This represents all that is 

 positively known about the condition of the lake, and on 

 comparing it with the residual mass curve, constructed from 

 the Sydney rainfall record (Plate 2, fig. 1) the value of the 

 new system I have adopted of showing tin: cumulative effect 

 of the rainfall, as exemplified in the Sydney residual curve, 

 became apparent to me, and all doubt as to the correctness 

 of the earlier Sydney register of rainfall was at once 

 removed. I then plotted on the diagram the Adelaide, 

 Horsham, Bathurst, and Hobart curves, and, making allow- 

 ance for local circumstances, there appeared to me to be 

 evidence of periodicity which, although it was not in strict 

 accordance with the nineteen years theory, still I felt con- 

 vinced that a marked change at that interval was clearly 

 observable in all the curves. 



Devoting my attention to the Lake George curve, it 

 occurred to me that it closely resembled a complete period, 

 rising, as it does, out of the dry bed of the lake to a maxi- 

 mum of 21 feet of water in 1875, and returning again to 

 the dry bed after a period of 57 years. Working on that 

 assumption I extended it backwards into the past from the 

 year 1820, in the manner you see on the diagram. I also 

 wrote in the general character of the weather in New 

 South Wales, as obtained from Mr. Russell's paper of 187G, 

 from the date of arrival of the first colonists in 1788 up to 

 the time when the rainfall began to be registered in 1831. 

 On comparing this with the assumed level of the water in 



