Notes on the Design of Telescope Tubes. 25 



During the trial the bulging in and bulging out of the 

 extended and compressed sides of Fig. 2 were plainly visible ; 

 but no such distortion of Fig. 1 was to be detected, although 

 its diameter was repeatedly tried with callipers. 



Art. VI. — Notes on the Coast Line Formation of the 

 Western District, and Proofs of the Uniform Condi- 

 tion of Meteorological Phenomenco over long periods of 

 timiC 



By Mr. T. E. Kawlinson, C.E., &c. 



[Read on the 14th June, 1877.] 



Two years ago a very interesting paper, by Mr. R. Etheridge, 

 on the sand dunes of the coast of Victoria, was read before 

 this Society ; and I purpose following up the subject by a 

 few notes of personal observations on the same subject, 

 connecting it with volcanic phenomena of the locality. 



My observations are chiefly confined to the portion of 

 coast line from a few miles east of Warrnambool to a few 

 miles west of Belfast. 



My object in doing so this evening is to bring forward 

 evidence which I consider conclusive in reference to estab- 

 lishing the fact of the permanence in this locality over great 

 periods of time of climatic conditions, and the several 

 changes in the coast line during the same period. 



The present coast line from the Biver Hopkins, east of 

 Warrnambool, to the Yambuk Lake entrance, about ten miles 

 west of Belfast^ is the third and last line of beach, and 

 consists chiefly of pulverised shells ; and, as Mr. Etheridge 

 points out, echini spines and other marine remains, to which 

 I may add enormous quantities of calcareous operculums, 

 which, from their great strength, have borne with impunity 

 the bruising which has mostly destroyed the parent uni- 

 valves, although in places there are many of these univalves 

 yet left on the dunes, together with the helios limpet and 

 more ordinary bivalves of the present sea. 



In all cases where I have tested the so-called sand with 

 acids, 80 per cent, and upwards has dissolved, leaving a 

 small residuum of reddish mud or clay, and the remainder 

 particles of silica (or sand). 



