ANIMAL PRODUCTS 153 



irritating substance which causes them discomfort. 

 Linnaeus, the Swedish naturalist, was the first to 

 make this fact known, and for the purpose of 

 establishing the truth of his discovery he inserted 

 some pieces of wire through the shells of some 

 oysters, with the result that, in due course, they 

 became covered with a calcareous and pearly 

 deposit. The Chinese have taken advantage of 

 this discovery, and make a practice of introducing 

 little metal figures (usually representing Buddha in a 

 sitting position) between the shells of oysters, which, 

 when coated with the pearly substance, are sold to 

 the populace as charms. The pearl-oysters also 

 yield the material known as ' mother-of-pearl,' 

 which is used largely in the manufacture of buttons ; 

 and the large transparent shells of a certain oyster 

 form a substitute for glass in Southern China and 

 India. Mr. Simmonds tells us that the shells of 

 oysters, mussels, and snails are used as drinking 

 vessels, spoons, etc., by many savage people, and, 

 in New Zealand, they are sharpened and employed 

 as razors. The natives of the South Sea Islands 

 convert them into fish-hooks, and, in North America, 

 harpoons are often tipped with sharp pieces of 

 mussel shell. Cowry shells take (or used to take) 

 the place of money in many parts of Southern Asia 

 their value being roughly estimated in comparison 

 with our coins at the rate of 4,000 to the shilling. 

 It is recorded that a church, which cost 4,000 to 

 erect in the East Indies, was entirely paid for with 

 cowry shells, of which about 36,000,000 were re- 

 quired to pay the wages of the workmen. 



