#6 Thomas Edison: Cocaine

Thomas Alva Edison was an American inventor and businessman. He developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and a long-lasting, practical electric light bulb.

Edison's name always gets thrown around at the mention of any interesting conversation about sleep. Supposedly he only slept four hours a night. This very likely had something to do with his love of Vin Mariani, which was essentially wine with cocaine in it.

#7 Carl Sagan: Marijuana

Carl Edward Sagan was an American astronomer, astrophysicist, cosmologist, author, science popularizer and science communicator in astronomy and natural sciences. Sagan is known for his popular science books and for the award-winning 1980 television series Cosmos: A Personal Voyage, which he narrated and co-wrote.

Carl Sagan kept his casual marijuana use secretive, writing an essay extolling the plant's virtues under the pseudonym Mr. X for a 1969 book called "Marihuana Reconsidered." He wrote, "the illegality of cannabis is outrageous, an impediment to full utilization of a drug which helps produce the serenity and insight, sensitivity and fellowship so desperately needed in this increasingly mad and dangerous world.”

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