SYSTEMATIC ANALYSIS OF ORGANS. 131 



488. THE STUDENT WILL CONCLUDE, as he glances 

 over the large number of organs and their uses, that 

 they must be composed of a great number of substances. 



489. HE WILL BE SURPRISED AND DELIGHTED TO 



LEARN that only six kinds, modified as circumstances re- 

 quire, with their inherent properties, are necessary. 



490. IF HE CAREFULLY INSPECTS ALL THE ORGANS, 



he will perceive that whatever their forms, textures, at- 

 tachments, or uses, they are only required to form fluids, 

 or to contract, or to excite, or to be tough and flexible, 

 or to be firm and elastic, or to be rigid or several of 

 these at the same time. 



491. Illus. The Heart is a pouch that requires to 

 be formed of a substance tough and flexible, of one that 

 can contract, of one that can excite contraction, and of 

 one that can form a fluid to keep its surfaces glairy and 

 free from friction four substances, having four properties. 



492. THE STUDENT CANNOT NAME an organ the use 

 of which requires more or other than the six substances 

 with the properties mentioned. 



493. TISSUE is the name given to the substances of 

 which the organs are composed. 



494. PROPERTY is the name given to the peculiar char- 

 acteristic that renders a tissue serviceable in an organ. 



495. The names of the Tissues and Properties are 



as follows : 



PROPERTIES. 



{Bony or Osseous, Rigid. 



Gristly or Cartilaginous, Firm and Elastic. 



Sinewy or Fibrous, Tough and Flexible. 



( Nervous, To Excite. 



(^ Active < Muscular, To Contract. 



( Secretory, To Secrete. 



The composition of the organs and the character of 

 the tissue will be, perhaps, made more impressive by 

 the subjoined synopsis of the Tissues composing each 

 organ. The figures refer to the number of varieties of 



488. What ? 489. What ? 490. What ? 491. What is the heart ? 492. What 

 ? 493. What is ? 494. Define . 495. What ? Write and explain table. 



