How to put different template types into one vector

I'd like to construct a message with unknown length or number of arguments. I took a simple template like

template <typename T> class Argument {
public:
    int size;
    int type;
    T data;
};

and with some overloaded

addMessage (int value) {
    Argument<int> *a = new Argument<int>;
    vec.push_back(a);
}

(same for string and so on) I try to push it all into one vector. I tried

std::vector<Argument* > vec;
std::vector<Argument<typename T>* > vec;
std::vector<Argument<>* > vec;

but nothing of this seems to work. Is there a way to do this? Thanks in advance.