26 CRAB, SHRIMP, AND LOBSTER LORE. 



Avho are disposed to grapple with the subject for its 

 own sake. 



The change of colour wliich takes place in many of 

 the Crustacea during the process of boiling, has long 

 been a subject of remark. The common and edible 

 Crabs of this country have their tints far less affected 

 than the lobster, the peculiarly rich blue shade of 

 whose shell when in a living state is too well known 

 to need any lengthened description ; this, as is well 

 known, changes to a bright red in the cooking-pot, and 

 the uniform of the police is exchanged for that of the 

 line regiments. This strange metamorphosis, researches 

 have shown to be entirely dependent on chemical laws. 

 The pigment on which the blue shading and tint de- 

 pend, is a peculiar fat-like substance, which possesses 

 the singular property of becoming scarlet when sub- 

 jected to 70 degrees of heat shown in the centigrade 

 thermometer. A colouring matter of very similar 

 properties was some time since discovered in the beaks 

 and legs of certain birds. 



The lobster pigment is soluble in spirits of wine, by 

 which agent it can be extracted from the shell ; but the 

 colour changes at once from blue to red. And on add- 

 ing either nitric or sulphuric acid, the charged spirit is 

 changed to a green of a remarkably fa&t or permanent 

 character. Who shall say, as fresh discoveries are 

 made and new solvents brought to light, that lobster 



