74 THE OTSTEK. 



It also contains a great quantity of particles of salt, the 

 same as that of the sea-water in which it lives. 



The oyster-liquor, or, as I have said, more properly 

 speaking, its life's blood, contains a great amount of 

 hydroidum, kali, sulphur of lime, sulphur of magnesia, 

 some organic matter, osmazone, and a very little salt. 

 The shell is composed of a very intimate mixture of 

 salt, carbonic lime, and animal mucus. It exhibits, 

 also, phosphate of lime and magnesia in smaU quanti- 

 ties, as also sulphuretted hydrogen. 



At the moment in which natural death ensues, all 

 animal matter begins to show its chemical affinities by 

 separating again into the elements of which it consists ; 

 and as at such times it is always more or less of a 

 poisonous nature, it is well to study the method by 

 which it may be known whether an oyster was living 

 or dead when its shell is opened. This can be seen at, 

 a glance. If the muscle appears sunk, it is a proofs 

 that the animal was living; but if it appears higher 

 and above the oyster, it was dead before it was opened, , 

 and the animal is, consequently, unwholesome and unfit 

 for food. 



