The advanced scientific treatment of disordered, and diseased liver in the human subject, by administering fresh animal extracts procured from the prepared healthy livers of sheep, the ox, and other such animals, is discussed elsewhere under their several headings. Pate de foie gras, compounded for nutritive purposes from the livers of specially fattened geese, is a case in point, as it has been described with reference to those domestic birds. It was Sydney Smith who gave us his notion of heaven, as: "eating foie gras to the sound of trumpets".

"The liver of the Hare," told Cogan, in his Haven of Health (1589), "when dryed, and made in powder, is good for those that be liver-sick." Again, the liver of an edible Tortoise, or Turtle, is a special delicacy (the taste for it being an acquired one), when eaten with lemon, pepper, and salt, after the gall bag has been first removed. This delicacy is much appreciated by many invalids when they cannot take other kinds of food, and it serves to assist biliary digestion.

Animal liver, and kidneys, resemble one another in being structurally compact solid organs, which contain but little connective tissue. This physical property renders them somewhat difficult to be digested unless they have been minced before cooking, or are thoroughly masticated when eaten. Chemically they both consist chiefly of proteid, together with a small amount of fat; but this proteid is quite different from that of ordinary meat, consisting as it does to a large extent of nucleo-proteid, which yields nuclein during digestion. Now it has been recently proved that nuclein is an important source of uric acid; and therefore it must be the more prudent course for persons goutily disposed to avoid the dietetic use of these articles of food. Moreover, "sheep's liver furnishes over 6 per cent of xanthic acid, a uric, or gouty element;" thus teaches Dr. Haig. As long ago as 1710, in Solomon, Matthew Prior bade his readers "try if life be worth the liver's care"; and Mr. Punch has more lately borrowed the play of words: "Is life worth living?" he asks, and replies humorously, "that depends on the liver".

The good city of Liverpool gets its name not from the bile-making organ, but from the Ibis (Falcinellus igneus ), a bird which when adult has its plumage mainly liver-coloured, or hepatic. Curative preparations, and methods for making them, from liver of the calf, sheep, and domestic fowl are described at length in Kitchen Physic. The help afforded against active bleeding from the lungs in consumptive disease by giving fresh, healthy animal liver daily as a food, in small quantities, three or four ounces, lightly cooked, and because of its ferment as coagulating the blood, has been definitely explained. The same liver dried and powdered, if administered as a medicament, is similarly of efficient service, though in a less degree.