A GREAT MARINE MUSEUM 



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The collection of biological gear and tackle is much less complete 

 and less advantageously displayed. There are samples of dredges, 

 tangles, trawls, tow-nets, plankton nets, plankton nets of the Hensen, 

 closing-net of Xansen and young-fish net of the Helgoland pattern. 



The oceanographical exhibit in rooms 8 and 9 is original in design 

 and execution and contains unique and instructive displays designed to 

 facilitate by comparative methods the quick and easy comprehension of 

 the fundamental facts of oceanography. Marble blocks are used to 

 represent the relative volumes of the globe, the sea, the land above sea- 

 level, and in the continental blocks (above 2,300 m. belnw sea-level). 

 In a similar way their relative weights and those of the atmosphere 

 and of the dissolved salt in the sea are shown, as are also the quantity 

 of salt and the proportions of the various substances dissolved in sea 

 water. A very striking illustration of the quantity of salt in the sea 

 is shown by a comparison, to scale, of the thickness of the crust left on 

 the sea bottom on evaporation of the sea, with a model of the royal 

 castle at Berlin to the same scale. The relative elevation of the con- 

 tinents and depths of the seas are shown by plastic reliefs. Models of 

 a transatlantic liner on columns of blue glass bring in vivid contrast 

 the conditions as to depth in the North Sea, the Atlantic and the 

 greatest known ocean depths. Movable mechanisms illustrate wave 

 motion, while the effect of breakers on steep and flat coast line is shown 

 by photographs and examples of erosion. 



The biological exhibits are striking in their design and educative in 

 purpose. There is little attempt at a systematic exhibit of marine 



Fig. 3. Biological Exhibit. Coral reef from the Red Sea. 



