There has developed within the city limits of Pittsburgh, and the adjoining territory that rounds out the boundaries of Allegheny County, and for more than a score of miles along the three rivers that converge at the Point, a region that is known as “the workshop of the world.” The tremendous industrial and commercial expansion of this area in recent years is well known, but “the roots of the present lie deep in the past” and the origin or background of this development is somewhat shrouded in obscurity.