58 waltee shellshear. on the treatment of 



Discussion. 



Mr. Russell — I am one of those who admire the ingenuity 

 and perseverance displayed by Mr. Hargrave in his attempts to 

 produce a perfect flying-machine. I congratulate him upon the 

 production of those ingenious models intended to copy the methods 

 followed by nature to produce motion in various animal organiza- 

 tions. I think it is greatly to his credit that he now willingly 

 admits he finds after experiment that he can attain far better 

 results with a simple form of mechanism than with that of a com- 

 plex nature. He has introduced several important inventions in 

 connection with his scheme, which in the case of most men would 

 have been taken to the Patents Office without delay, but which 

 he from pure love of science freely gives to the world as part of 

 his flying-machine. I have much pleasure in proposing a vote of 

 thanks to Mr. Hargrave for his interesting paper. 



The President — Mr. Hargrave has my best wishes for the 

 success of his experiments. It would be a very gratifying thing 

 if a really practical flying-machine were invented by an Australian. 

 They say the proof of the pudding is in the eating, and the success 

 of this invention will be proved when we see him fly across to 

 North Shore (Laughter). I wish him every success. 



ON THE TREATMENT OF SLIPS ON THE ILLAWARRA 

 RAILWAY AT STANWELL PARK. 



By Walter Shellshear, Assoc. M. Inst., C.E. 

 [With One Diagram.] 



[Read before the Royal Society of N.8.W., June 4, 1890.'] 



In locating a railway the engineer often finds himself forced to 

 carry his line through country of a more or less treacherous and 

 rotten nature, where the difficulties of maintaining the earthworks 

 become a very formidable problem, and perhaps few illustrations 

 of this could be found where the difficulties have been more serious 

 than on the Illawarra Line, between Otford and Bulli. In this 

 case there was no choice between carrying the line through almost 

 a continuous tunnel or facing the difficulty of carrying it over 

 ground of the most treacherous nature. At Stanwell Park the 



