One hundred fifty years ago today, the great Centennial Exhibition was underway in Philadelphia, and Alexander Graham Bell decided to go. “Dear Mama," he wrote.

"Here I am in New York on my way to Philadelphia…. It will be of extreme importance to me to meet Sir William Thomson [Lord Kelvin] and other prominent electricians—so as to interest them in my inventions.”
#telephone

https://around.com/8170-2/