Clark, Alvan (18041887), a United States maker of astronomical lenses. Five times his firm, Alvan Clark & Sons, made the then-largest telescope lens in the world. The fifth one, completed 10 years after his death, is the 40-inch (102-cm) refractor at the Yerkes Observatory at Williams Bay, Wisconsinstill the world's largest. Clark was born in Ashfield, Massachusetts.
Clark, Alvan
You Might Also Like
How Stephen Hawking Works
He's ventured to the abyss of black holes, wagered on the information paradox and floated around in zero gravity. Meet the man, the legend, the super scientist: Stephen Hawking.
How Isaac Newton Worked
The man immortalized on the left was behind the three laws of motion and the universal law of gravitation. He was also competitive, temperamental and fascinated with alchemy. How well do you know Newton?

