It will be seen from many of the above cha racters, that picromel (by which we mean Ber zelius's Gallenstofi) has probably been mistaken for albumen, and that it is not improbable that the only true albuminous part of the bile may be in that equivocal state which is often called mucus, and which is especially distinguished by being precipitable by acetic acid. Berze lius has suggested an analogy between picromel and the peculiar saccharine matter which is contained in liquorice-root; and in many re spects their chemical properties are identical.
In the preceding statement, drawn princi pally from Berzelius, we have endeavoured to give the simplest view of the analysis of the bile; namely, the separation of its muco-albu men by acetic acid or alcohol, and of its picromel, by precipitation with acids and subsequent decomposition of the precipitate by carbonated baryte or alcali ; its saline contents appear closely to resemble those of the serum of the blood ; like which it has an alcaline due to soda. We have also selected such periments, as, with us, have invariably suc ceeded : the following results, therefore, of the analysis of the bile, as given by Berzelius, will now be intelligible.
The details of the other analyses of the bile as given by the authorities to which we have referred above, would be unintelligible if abridged, and are too voluminous, and too ex clusively chemical, to be inserted here; and moreover, we have generally failed in arriving at satisfactory conclusions in our endeavours at a repetition of the various analytical operations which are described; we must therefore rest satisfied with giving, in a condensed a general statement of their results. According to Thenard, human bile contains, water 90.90 ; yellow bitter resin 3.73 ; yellow matter gene rally diffused through the bile (mucus and colour ing matter?) 0.18 to 0.90; albumen 3.82 ; soda, by which the resin is dissolved, 0.51 ; phos phate, sulphate, and muriate of soda, phosphate of lime, and oxide of iron, 0.41. Tiedemann and Gmelin give the following as the compo nents of human bile: 1. fat; 2. brown resin ; 3. sweet principle of bile; 4. salivary matter; 5. mucus; 6. gall-brown (colouring matter?);
7. oleic acid, salts, and minute quantities of other substances. From mherz and !C_;ugert'' have arrived at yet more complicated results: namely, 1. fat ; 2. resin ; 3. sweet principle; 4. osma- zome; 5. salivary matter (Speichelstoff); 6. ca seum ; 7. mucus; 8. margaric and other fatty acids, with phosphate, muriate, and sulphate of soda and potash ; and carbonate, phosphate, and sulphate of lime. The above, and other chemists, have published analyses of bile, taken after death in various diseases, but they present nothing very important. Tiedemann and Gme lin's elaborate analysis of ox-gall deserves the perusal of all chemists concerned in such in quiries : it contains, according to L. Gmelind a substance not to be found in any other bile, and which he has called faurin or Gallenaspa ragin: it may be obtained as follows :--add muriatic acid to ox-gall and filter; after a few days a fatty matter appears, which is separated by filtration; the filtered liquid is evaporated to a small bulk, when it separates into two parts, a resinous mass and a sour fluid : the latter, upon further evaporation, yields more resinous matter, and at length crystals of corn mon salt and taurin, which are to be separated, and the latter purified a second by crystalli sation. Taurin, when purified, is in prismatic crystals, neither acid nor alkaline, not altered by exposure to air, inodorous, of a peculiar taste : soluble in about fifteen parts of cold wa ter, and nearly insoluble in absolute alcohol : it is fusible, and not decomposed by nitric acid.
In concluding this subject, we must again express our conviction that many of the sup posed proximate components of bile are pro ducts of the various operations and re-agents to which it has been submitted, and that the ana lysis of Berzelius, which is the simplest, is probably the most correct : from the uncertain operation of various precipitants upon bile, and from the facility with which the results vary, apparently in consequence of very trifling causes, there seems to be a peculiar tendency in its component parts to undergo hitherto unex plained modifications.