From the standpoint of legal supervision, consequently, the affairs of such a corporation are divided into a series of compartments, each compartment being determined by certain arbitrary geographical lines--lines which do not, like the boundaries of a municipality, correspond to any significant economic division.

As long as such a method of supervision endures, no effective regulation of commerce or industry is possible.

A corporation is not a commercial Pooh-Bah, divided into unrelated sections.

It is an industrial and commercial individual.

The business which it transacts in one state is vitally related to the business which it transacts in other states; and even in those rare cases of the restriction of a business to the limits of a single state, the purchasing and selling made in its interest necessarily compete with inter-state transactions in the same products.