170 Coral Reefs and the Glacial Period. [April, 



A few words more before concluding on the management 

 of existing railways as they stand. It has been taken for 

 granted that, where high speeds are adopted, no substantial 

 change can take place in the strength of the vehicles or the 

 weights of the engines ; but why should not express stock 

 be kept distinct, and a considerable reduction be made in 

 that which is meant for ordinary service ? Such an eco- 

 nomy is being effected on the South London Raifway by 

 the present locomotive superintendent, Mr. Stroudley, who 

 has constructed some light and neat carriages, with central 

 buffers, drawn by small engines weighing only 23 tons ; 

 these trains are worthy imitation — they are a step in the 

 right direction, and if more fully adopted would give better 

 dividends and reduced fares. The real fact is, that great 

 obstacles are placed in the way of railway officials, in con- 

 sequence of the division of their responsibility. The loco- 

 motive superintendent thinks little about the permanent 

 way — which is not under him, but adopts great strengths 

 and weights, whereby he increases the "life" of his stock. 

 The engineer who has charge of the permanent way com- 

 plains, but has no remedy. No real improvement is possible 

 until some ruling mind governs each system, and insists 

 upon comprehensive reforms and the adoption of those 

 inventions which guarantee sure economies. 



III. CORAL REEFS AND THE GLACIAL PERIOD. 



By J. Clifton Ward, F.G.S. 

 Of the Geological Survey of England and Wales. 



HERE is nothing which so much helps forward geo- 

 logical science as the study of our globe as it now is. 

 Every fresh discovery in physical geography helps to 

 explain some hitherto mysterious geological fact. The 

 greater part of the world has yet to be travelled over 

 scientifically, and when this is done, the geological science 

 of that day will probably be as much in advance of our 

 present knowledge as our to-day's science is of that of 

 twenty years back. 



Geology made a great advance when Darwin explained 

 the mystery of coral reefs, for by their accurate study, 

 geologists learnt how slowly and gradually large tracts of 

 land were submerged, and' in what way great thicknesses 

 of limestone could be formed — not by the preservation so 



