Samuel Andrews

Kerosene is packaged, transported, and sold, and it's offered opportunities to someone who believed that cost could be controlled within this kind of staple technology.

So in 1863, Rockefeller, Clark, and an English-born chemist named Samuel Andrews enter refining.

Andrews possessed this very deep technical expertise, and Rockefeller increasingly supplied more commercial discipline.

So in 1865, after this kind of tension between the partners, the refinery was auctioned among them.

And he did this by scrutinizing the cost of barrels, chemicals, storage, freight, financing, and the overall handling of these materials throughout that process.

And that preference for kind of extracting value from the whole process would eventually develop into what most scholars and business professionals call vertical integration.

As his partnership structure evolves, Samuel Andrews, who is that kind of very deep technical expert, remains increasingly more important on the refining side.

Rockefeller's brother, William, also joins the enterprise at this point.