3 86 THE OCEAN WORLD. 



scrapes up, detaching the oysters, and throwing Jhem into a net 

 attached to the dredge. In this process oysters, large and small, are 

 torn from their native bed, some going into the net, but a larger 

 number are buried in the mud. It would be difficult to imagine a 

 more destructive process ; and when the habits of the oyster are 

 considered, it is evidently one admirably contrived to destroy the 

 race. 



In France oyster dredging is conducted by fleets of thirty or 

 forty boats, each carrying four or five men. At a fixed hour, and 

 under the surveillance of a coast-guard in a pinnace bearing the 

 national flag, the flotilla commences the fishing. In the estuary of 

 the Thames the practice is much the same, although no official 

 surveillance is observed. Each bark is provided with four or five 

 dredges, each resembling in shape a common clasp purse. These 

 dredges are formed of network, with a strong iron frame, as repre- 

 sented in Fig. 171, the iron frame serving the double purpose of 

 acting as a scraper, and keeping the mouth open, while giving it a 

 proper pressure as it travels over the oyster-beds. When the boat is 

 over the oyster scarp, the dredge is let down, and no more attractive 

 sight exists than that presented by the well-appointed Whitstable 

 boats on one side of the estuary, or the Colne boats on the other, 

 as they wear and tack over the oyster-beds, bearing up from time to 

 time to haul in the dredge, and empty its contents into the hold. 

 The tension of the rope is the signal for hauling in, and very hetero- 

 geneous are the contents of the dredge sea-weeds, star-fishes, 

 lobsters, crabs, actinia, and stones. In this manner the common 

 oyster-beds on both sides of the Channel were ploughed up by the 

 oyster dredger pretty much as the ploughman on shore turns up a 

 field. The consequence was that, twenty years ago, the French 

 beds were totally exhausted, and France had to look to foreign 

 countries for its oysters. Oyster-farms which had employed 1,400 

 men and 200 boats were reduced to employing 200 men and twenty 

 boats. Similar results from over-dredging would have followed, no 

 doubt, on this side the Channel had the mollusc not been protected 

 by the companies and private proprietors who held the oyster-beds 

 in the large estuaries. This state of things in France led to some 

 important discoveries in the science of oyster culture, which have 

 produced important changes there. 



The name of Sergius Grata has already been mentioned as a culti- 

 vator of oysters. He lived in the fifth century before our era, and 

 according to Pliny he first attempted parking oysters at Baia in the 

 time of the. orator Lucius Crassus. He was the first to recognise the 



