The person sitting next to me on a flight was a woman. Ever the charmer, I used one of my pick-up lines on her.
I asked, “Does the airline charge you extra for sitting next to good-looking men?”
“Yes,” she replied, “but I wasn’t willing to pay.”
Crystal rectifierIn 1874, a paper by Ferdinand Braun (1850-1918) was published in the Annalen der Physik und Chemie describing his discovery of the electrical rectifier effect. He observed that certain crystals of metal sulphides have a larger or smaller resistance to an electric current, depending on its direction of flow. He used a galena crystal, a semiconductor material composed of lead sulfide. He found the rectifying effect especially true if at least one of the electrodes was a pointed wire. Thus, he had discovered the point-contact rectifier effect, the first semiconductor device. This effect wasn't used until over 30 years later in the form of the “cat's whisker”crystal radio detector which ultimately led to the point-contact transistor first produced in 1948. |
