AN OBJECT OF THE BASE CLASS CAN 
ONLY USE BASE CLASS MEMBER FUNCTIONS.
Making a Mammal
A mammal is speaking.
Zzzzzz
I am a Mammal.
Destroying a Mammal


AN OBJECT OF THE DERIVED CLASS
CAN USE BASE CLASS AND DERIVED CLASS
MEMBER FUNCTIONS.
Making a Mammal
Making a Dog
Have pity on me! Please feed a hungry dog.
Zzzzzz
I am a Dog.
Wag, wag, wag!
Destroying a Dog.
Destroying a Mammal


A POINTER TO THE BASE CLASS
THAT POINTS TO AN OBJECT OF THE BASE CLASS
CAN USE BASE CLASS MEMBER FUNCTIONS ONLY.
Making a Mammal
A mammal is speaking.
Zzzzzz
I am a Mammal.
Destroying a Mammal


A POINTER TO THE DERIVED CLASS
THAT POINTS TO AN OBJECT OF THE DERIVED CLASS
CAN USE BASE CLASS AND DERIVED
CLASS MEMBER FUNCTIONS.
Making a Mammal
Making a Dog
Have pity on me! Please feed a hungry dog.
Zzzzzz
I am a Dog.
Wag, wag, wag!
Destroying a Dog.
Destroying a Mammal


A POINTER TO THE BASE CLASS
THAT POINTS TO AN OBJECT OF THE DERIVED CLASS
CAN USE MEMBER FUNCTIONS DEFINED IN THE BASE CLASS.  
**BUT** IT WILL USE THE VERSION DEFINED IN 
THE BASE CLASS FOR NON-VIRTUAL FUNCTIONS
AND THE VERSION DEFINED IN THE DERIVED CLASS
FOR VIRTUAL FUNCTIONS, IF ONE EXISTS.
Making a Mammal
Making a Dog
A mammal is speaking.
Zzzzzz
I am a Dog.
Destroying a Mammal