268 OYSTERS, AND ALL ABOUT THEM. 



this is a cruelty which should be avoided wherever sea- 

 water can be obtained, because it is neither the salt nor 

 the water which sustains the oyster's life, but the spores of 

 vegetation which abound in the sea, and by mixing salt 

 with fresh water we destroy even the life of the incipient 

 fresh-water plants which the latter contains. It is as great 

 a mockery as when Grumio proposes to give the famished 

 Katherine the mustard without the brawn, and need no 

 longer exist if oyster dealers, who cannot obtain sea-water, 

 would provide themselves with the prepared salts for the 

 instantaneous production of artificial sea-water, the recipe 

 for the preparation of which is as follows : 



" For ten gallons it requires sulphate of magnesia, 7^- 

 ounces ; sulphate of lime, 2f ounces ; chloride of sodium, 

 43^ ounces ; chloride of magnesia, 6 ounces ; chloride of 

 potassium, i^ ounce ; bromide of magnesium, 21 grains; 

 carbonate of lime, 21 grains." 



This should be allowed to stand exposed to the air in 

 a strong sunlight for a fortnight before it is used, during 

 which time a few growing plants of enteromorpha, or ulva % 

 should be introduced to throw off spores. These plants 

 cost about one shilling each in London. The water then, 

 when under the microscope, will be found to contain a 

 confervoid vegetable growth, which forms as nourishing a 

 food for the oyster as the spores of sea-weed in its ocean 

 bed. Oysters laid down in a large trough, and covered 

 with water, will continue to live and thrive for months ; 

 and it was to some such method as this that the Romans 

 were indebted for the preservation of their oysters in inland 

 stews. On no account should oatmeal, flour, or any such 

 dead stuff, be added, which only serves to make the water 

 foul and the oyster sick. 



