  In a previous paper, I found that the Weyl group $W(F_4)$ and Barns-Wall
Lattice $BW_{16}$ can be constructed using the rank $2$ tensor of the
quaternion. In the present paper, I describe how I were able to construct an
algebra, which is the subalgebra of the direct product of Hurwitz Quaternionic
integers $\mathscr{H}^4$, isomorphic to the automorphism $\text{Aut}(BW_{16})$
order $2^{21} \cdot 3^5 \cdot 5^2 \cdot 7$ of Barns Wall Lattice $BW_{16}$ by
functionally extending the rank of the tensor product of quaternions to $4$.
