  In the present paper we argue that the dyonic black hole spacetimes must be
studied within the theory of two electromagnetic potentials, and we use the
dyonic Reissner-Nordstr\"om solution to demonstrate that the field of the
monopole magnetic charge is correctly described by the $t$-component of the
dual electromagnetic potential. As a result, the Dirac string associated with
the $\varphi$-component of the usual electromagnetic 4-potential becomes just a
mathematical object, without any physical content, that arises in some
calculations when one employs unsymmetrical representations of the
electromagnetic field. We use three different, though equivalent, forms of the
electromagnetic energy-momentum tensor to calculate the Komar mass of the
Reissner-Nordstr\"om black hole, and in one case the Dirac string is linked to
the magnetic charge, in another to the electric charge, while the third,
symmetrical case, is string-free.
