Alexander Graham Bell letter to parents about telephone sells for $92,000 The letter instructs the Scotland-born Bell's parents on how to ground the telephone to avoid harm from lightning strikes. He instructs them to run a sturdy copper wire from their house to the duck pond and bury it there. "If you have a good connection with a permanently moist stratum of earth, you need never fear lightning and your posts will be safe," Bell wrote. The letter was written two years after Bell obtained the patent on the telephone and made his first call to his assistant, Thomas Watson. Bidding on the letter offered by RRAuction began in December and ended Wednesday, with the top bid coming in at $92,856. RRAuction Vice President Bobby Livingston wouldn't name the top bidder, but he described him as "a prominent document collector in Texas who has an eye for the best stuff." Livingston said the letter came from an archive kept by an associate of Bell's. He said the letter is particularly valuable because of Bell's detailed discussion and drawings. "You're not going to see a better Alexander Graham Bell on the market," Livingston said. Bell and his family moved to North America in 1870 and settled in Canada. Bell moved to Boston the following year, where he taught the deaf and became a professor at Boston University.