•62 



154 Transactions of the Royal Society of Victoria. 



Transactions of the Institute of C.E. England, 1883, on 

 Improvement of River Broye. Mr. Gangnillet gives the 

 form as 



h 



discharge = c x ^ K for floods 



and the maximum discharge is said to vary as a curve of an 

 equilateral hyperbola. 



Lieutenant P. P. L. O'Connell, Associate of Institute of 

 C.E., in January 1868, argued that the maximum discharge 

 from similar water-sheds varied as the curve of a common 

 parabola. 



On the whole, I think it may be agreed that a simple 

 formula can only be a rough approximation. 



For tolerably impervious surfaces, such as clay, a useful 

 simple approximate formula for the sectional area of a 

 waterway, is the following : — 



area of culvert in square feet == (area in acres) 

 only a rough approximation. 



In conclusion, I supply a few facts which have come under 

 my own observation, a list kindly supplied by Mr. Gordon, 

 and also a list that I have acquired from time to time from 

 various sources. I would also direct attention to a list in 

 Mr. Beardmore's Hydrology, and pages 94 and 95, Vol. XX. 

 Transactions of the Victorian Royal Society 1883 ; and hope 

 that some experienced in Hydrology may supply information 

 at some future date on this, to me, interesting subject. 



Some years ago, a borough was founded with a creek 

 through its centre. It was found to be a considerable detri- 

 ment. The local Council decided that it would be advisable 

 to remove two bridges and cover over a considerable part of 

 this creek. Their surveyor prepared a design with about 

 190 feet area waterway for 10,000 acres, and application 

 was made for a Government grant ; the grant was allowed 

 subject to approval of the Government Engineers. The 

 Government Engineers reported that the waterway was 

 excessive, and recommended that it should be reduced by J. 

 That surveyor was an obstinate man and would not cede 

 the third. Ultimately, the plan was approved and the 

 creek was covered, and I have seen floods over that many 

 times a year. I pulled that culvert up and put down a new 

 one 370 feet area. Since the time I refer to, a culvert was 



