2 THE HUMAN BODY. 



by pressure proves that internally there are harder and softer 

 solid parts; while the blood that flows from a cut finger shows 

 that liquid constituents also exist in the Body. The concep- 

 tion of complexity which may be thus arrived at from exter- 

 nal observation of the living, is greatly extended by'dissection 

 of the dead Body, which makes manifest that it consists of a 

 great number of diverse parts or organs, which in turn are 

 built up of a limited number of materials; the same material 

 often entering into the composition of many different organs. 

 These primary building materials are known as the tissues^ 

 ,and that branch" of anatomy which deals with the characters 

 t of the. tissues -.amd their arrangement in various organs is 

 known as. Histology j or, since it is mainly carried on with the 

 aid of the itik-rc^oope, as Microscopic Anatomy. If, with the 

 poet, we compare the Body to a house, we may go on to liken 

 the tissues to the bricks, stone, mortar, wood, iron, glass and 

 so on, used in building ; and then walls and floors, stairs and 

 windows, formed by the combination of these, would answer 

 to anatomical organs. 



Zoological Position of Man. External examination of the 

 human Body shows also that it presents certain resemblances 

 to the bodies of many other animals: head and neck, trunk 

 and limbs, and various minor parts entering into them, are 

 not at all peculiar to it. Closer study and the investigation 

 of internal structure demonstrates further that these resem- 

 blances are in many cases not superficial only, but that our 

 Bodies may be regarded as built upon a plan common to them 

 and the bodies of many other creatures: and it soon becomes 

 further apparent that this resemblance is greater between the 

 Human Body and the bodies of ordinary four-footed beasts, 

 than between it and the bodies of birds, reptiles or fishes. 

 Hence, from a zoological point of view, man's Body marks 

 him out as belonging to the group of Mammalia (see Zoology), 

 which includes all animals in which the female suckles the 

 young ; and among mammals the anatomical resemblances 

 are closer and the differences less between man and certain 

 apes than between man and the other mammals; so that 

 zoologists still, with Linnaeus, include man with the monkeys 

 and apes in one subdivision of the Mammalia, known as the 

 Primates. That civilized man is mentally far superior to 

 any other animal is 010 valid objection to such a classification, 

 for zoological groups are defined by anatomical and not by 





