The earliest European explorers plying the California seaboard noticed colorful slicks and little balls of tar floating on the surface of the coastal waters. At times the odor of tar wafted from the coast to the seafarers, one explorer noting that "the scent [is] as strong as that perceived in a store of tarred ropes." Native Californians used tar found in natural seeps to calk their canoes. Little could those explorers or natives foresee that California would become one of the leading oil producers in the world. California's historic place in oil production would probably surprise many baby boomers, too. Edward L. Doheny first tapped the large oil fields in Los Angeles, but the real story of California oil goes to a small hill rising east of Long Beach, Signal Hill, and one intrepid entrepreneur, Samuel B. Mosher.