Cloning members of a hierarchy

I've got various classes derived (directly or indirectly) from a
single base, and want a function to make a copy of a given object. My
code is along the following lines:

class Base {
  public:
  int b;
  virtual Base *clone() = 0;
  };

class Derived : public Base {
  public:
  int d;
  Base *clone() { return new Derived(*this); }
  };

Am I right in thinking that I need to include a definition of the
"clone" function for every class that I want to be able to clone
objects of? And that this would be true even if I didn't make it a
pure virtual function? And that there is no easy way round this, short
of using macros to "tidy" the code up? But conversely, am I right in
thinking that the automatically-generated copy constructors will do
the actual donkey work of making a copy of all the members at all the
levels for me?

(I was also going to include a question about a potential bug in VC++,
in which it complained about not being able to instatiate an abstract
class - but it turned out that the problem was that one declaration
was declared "const" and the other wasn't, so it was my fault.)

Thanks.
Paul.