ANIMAL STRUCTURE. 527 



Dr. Andrew Clarke, after having carefully studied the 

 appearances of sputa from patients under his care, says, 

 " that the microscopical inspection of expectoration affords, 

 at a very early period of consumption, definite information, 

 not otherwise attainable, regarding the nature of the 

 malady; and at all times must furnish valuable aid in 

 forming a prognosis regarding the cause of the complaint." 



The expectoration generally shows pus cells, lung tissue, 

 blood corpuscles and moleculo-granular material, mixed 

 with, at times, a small amount of fat corpuscles. 



The space allotted to this division of our subject enables 

 us to give only a short and imperfect sketch of a few of 

 the fundamental tissues of the animal body. First, enu- 

 merating merely the elementary substances recognised by 

 chemistry as entering into the formative processes, we shall 

 proceed to inquire into that most interesting and wonderful 

 starting-point of life, the cell; admitted to be, and indeed 

 demonstrable as, the common centre alike of animal and 

 vegetable organisms. 



THE HUMAN BODY, ITS PHYSIOLOGICAL COMPOSITION AND 

 CHARACTER. 



The elementary substances found in the human body are 

 oxygen, hydrogen, carbon, azote, phosphorus, sulphur, 

 chlorine, fluorine, iron, manganese, titanium, and lime. 

 Silenium is found in the hair, and fluorine in combination 

 with lime forms the enamel of the teeth. Iron is the 

 colouring-matter of the blood, the black pigment of the 

 choroid of the eye, and in the skin. 



Manganese is found in the bones, hair, blood ; titanium 

 in the salts from the supra-renal capsule. Other substances 

 and gases are found distributed throughout the body. 



Azotised and mw-azotised substances constitute the 

 proximate organic principles. The azotised are, protein 

 and its compounds, albumen, fibrin, casein, and pepsin ; 

 extractive matters, gelatine, hsematine, cholestrine or bile 

 matters, urea, and uric acid. The ^oft-azotised are, lactine, 

 or sugar of milk, and fatty matters. 



Cells. All animal and vegetable structures, the micro- 

 scope has revealed to us ; are developed from cells ; the 



