38 THE MICROSCOPE. 



creasing the soil of every land, and laying anew 

 the foundations of every sea ! 



3. The Naturalists of the United States' recent 

 exploring expedition brought up thousands of 

 Diatomacece by every cast of the deep-sea sound- 

 ing apparatus, alike in the Atlantic, Pacific, and 

 Australian oceans. According to Dr. "W. J. 

 Hooker, these Microscopic vegetables abound 

 throughout the South Polar Sea, between the 

 parallels of 50 and 70 S. Diatomacece exist 

 everywhere, stain the ice of a brown colour, 

 or when put into water, render it cloudy like 

 inilk, and take hours to subside. A deposit of 

 mud, 400 miles long, and 200 miles in breadth, 

 stretches along the shores of the Victoria Bar- 

 rier, and wherever soundings were here made, 

 the average depth of the water being 1800 feet, 

 they were invariably charged with diatomaceous 

 remains the immense deposit being thus 

 proved to consist chiefly of these Microscopic 

 organisms. 1 The Paris Basin, 180 miles long, 

 and 90 miles in breadth, abounds in infusoria 

 (so called) and other silicious remains. 2 



1 Dr. Hooker's Flora Antarctica, vol. ii. pp. 503-505. 



2 Hogg on the Microscope, p. 156. 



