virtual void Medium(Int_t& kmed, const char *name, Int_t nmat,
Int_t isvol, Int_t ifield, Double_t fieldm, Double_t tmaxfd,
Double_t stemax, Double_t deemax, Double_t epsil,
virtual void Medium(Int_t& kmed, const char *name, Int_t nmat,
Int_t isvol, Int_t ifield, Double_t fieldm, Double_t tmaxfd,
Double_t stemax, Double_t deemax, Double_t epsil,