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POrULAR SCIENCE REVIEW. 
pressure of the superincumbent water kept the valves closed, 
and the water which last passed into the bottle was retained 
there. That “ bottom water ” really was brought up, the 
A B 
Water-bottle as seen at A externally, and at B^in section ; drawn to 
a scale of one-eighth the actual size. 
writer had ample evideiye, as from the greatest depths it~was 
cloudy with suspended mud, minute Grlobigerinae, and other 
Foramenifera. 
The dredges with which the expedition was provided were 
the ordinary form of “ naturalist’s dredge ” introduced^by Ball 
and Forbes. They were made of wrought iron, the scrapers 
being pitched at a very low angle, and the arms being 
moveable. One of the arms was in two pieces, terminating in 
rings, which were fastened together by a few turns of spun 
yam, so that, when the dredge got fouled by rocks, as occasion- 
ally happened in depths less than 500 fathoms, the strain upon 
the dredge broke the “stop,” the dredge changed its position, 
and freed itself. The loss of several dredges was avoided by 
this simple precaution. For very deep dredging, the weight_of 
