Birds in a domestic state do not readily become fat, if allowed to go at large; for this purpose, they should be confined in coops, and supplied with as much wholesome food as they can eat. Poulterers even cram them with food. Domestic water fowls, must, while fattening, be kept from the water, otherwise they will acquire a strong fishy taste, and besides, will always remain lean. In general, over fatness may be considered as a sort of oleagenous dropsy, and seldom or never is met with in a state of nature. All the soft parts of fish contain gelatine and fibrous substance, and are, consequently, in the edible sorts, nutritious. The fibrous portions are not, except in a few species, red, like the muscular flesh of land animals, but white and opake when dressed. If cooked fish looks bluish and semi-transparent, it is not in season. It is fortunate for us, that few if any poisonous fish are found in our seas, being chiefly confined to the tropics. The roe of the greater number of fishes is eaten: caviar is the roe of the sturgeon. Cods sounds, or the swim bladder of the larger cod, are reckoned a great delicacy when properly preserved. It is not usual for the skin of any animal to be eaten, though the skin of some sorts of fish which are pulpy and gelatinous are relished--as the skin of calves head is used for mock turtle soup. The flavour of fish depends greatly on their food, which, it is supposed, is the main cause of the difference between fresh and salt water fish, and between the same sorts of fish taken in different lakes and rivers, and on different parts of the coast. Some shell fish, such as muscles and cockles, are occasionally found to disagree with some particular constitutions, but it is not true that this arises from their feeding on copper banks; some say, that it is from the persons eating the beard or fibres, by which the muscles attach themselves to the rocks, which is not, we think, probable. The limpet (_Patella vulgata_), the periwinkle (_turbo littoreus_) and whilk (_murex antiquus_), are used as food, boiled by the common people in various districts of this country. The crustaceous shellfish of sufficient size, are very generally esculent. These chiefly belong to the family of _Cancer_. Hence, several species of crabs, both short and long tailed, are eaten. The lobster, the crawfish, the shrimp, and the prawn belong to this class. OBSERVATIONS ON THE VARIOUS KINDS OF VEGETABLE SUBSTANCES COMMONLY USED FOR FOOD.