46 MATERIAL COMPOSITION OF MAN. 



many articles of vegetable and animal food ; in gelatin from bones, for 

 example, in sorrel, chocolate, bread, coffee, succory, madder, and sugar. 

 The ashes obtained from starch sugar yielded 4 per cent, of copper ; 

 those of gelatin, 0'03 per cent.; and those of bread, 0*005 to 0*008 

 per cent. 1 It is now generally considered to be present in the human 

 liver, 2 and M. E. Millon 3 asserts, that human blood invariably contains 

 lead, copper, silica, and manganese. 



11. Silicium. Silica is found in the hair, bones, blood, urine, and 

 in urinary calculi. 



12. Chlorine. In combination with hydrogen, and forming chloro- 

 Jiydric acid, chlorine is met with in most of the animal fluids. It is 

 generally united with soda. Free chlorohydric acid has also been found 

 by Dr. Prout 4 in the stomach of the rabbit, hare, horse, calf, and dog ; 

 and he has discovered the same acid in the sour matter ejected from 

 the stomachs of those labouring under indigestion. Mr. Children, and 

 Messrs. Tiedemann and Gmelin, 5 made similar observations ; and Pro- 

 fessor Emmet and the author 6 found it in considerable quantity in the 

 healthy gastric secretions of man. 



13. fluorine. This simple substance has been found combined with 

 calcium -fluoride of calcium in the enamel of the teeth, bones, and 

 urine. 



14. Sodium. Oxide of sodium, soda, forms part of all the fluids. 

 It has never been discovered in a free state ; but is united (without an 

 acid), to albumen. Most frequently, it is combined with chlorine, and 

 phosphoric acid; less frequently, with lactic, carbonic, and sulphuric 

 acids. Chloride of sodium is contained in most of the animal secre- 

 tions ; and from its decomposition may result the chlorohydric acid of 

 the gastric juice, and a part the soda of the bile and other fluids. 



15. Potassium. The oxide, potassa, is found in many animal fluids, 

 but always united with acids sulphuric, chlorohydric, phosphoric, &c. 

 It is much more common in the vegetable kingdom ; and hence one of 

 its names vegetable alkali. 



16. Magnesium. The oxide, magnesia, exists sparingly in bones, 

 and in some other parts ; but always in combination with phosphoric 

 acid, and appears to be always associated with calcium. 



17. Aluminium. Alumina is said by Morichini to exist in the ena- 

 mel of the teeth. Fourcroy and Vauquelin found it in the bones ; and 

 John, in white hairs. According to Schlossberger, it is in the flesh of 

 fishes. 7 



18. Titanium. Dr. Eees affirms, that he detected it in salts ob- 

 tained from the supra-renal capsules. 



1 Lond. Med. Gaz., Dec. 1, 1843, from Gazette Medicale de Paris, and Mr. Paget,Rep. on 

 Anatomy and Physiology, 1843-4, in Brit, and For. Med. Rev., Jan., 1845, p. 249. 



2 Kirkes and Paget, Manual of Physiology, Amer. edit., p. 29, Philad., 1849. 



3 Comptes Rend us, Paris, 1848. 



< Philosoph. Transact, for 1824, p. 45. 



5 Recherches Experimental, &c., sur la Digestion, trad, par A. G. L. Jourdan. Art. 4, p. 

 94, Paris, 1827. 



6 See under the head of " Digestion," and the author's Human Health, p. 19*1, Philadelphia, 

 1844. 



7 Henle, Allgemeine Anatomic, s. 4. Leipz., 1841, or Jourdan's translation, i. 2, Paris, 

 1843. 



