Are all types of let bindings in classes private ?

I have a simple class with some let bindings:
-----Sample class -------------------
#light
namespace JustToTest

type Foo() =

// is compiled as private
let myVar = "sdfas"

/// is compiled as public
let add(a,b) = a + b
------------------------------------------

When I compile this example to a DLL and reflect over it in Visual Studio´s Object Browser I see that the function add() is public. Furthermore it has a strange name: add@10 :

------- Visual Studio`s Object Browser -------------
public int add@10(int a, int b)
Member of JustToTest.Foo
--------------------------------------------------------------

Is it OK?

How can I make this value private?
The compiler refuses to declare this function as private:
/// does not work
let private add(a,b) = a + b