I was reading this wiki entry about the US Balloon Corps, and this part confused me: "From a height of 500 feet (150 m) he telegraphed a message to the President describing his view of the Washington, D.C., countryside."
Now, I don't exactly get how communications in general worked back then, but wasn't telegraph cable-only?
If you look further down in the Wikipedia article^1 you'll see:
On Saturday, 16 June, with his own balloon, the Enterprise, Lowe ascended some 500 feet (150 m) above the Columbian Armory with a telegraph key and operator, and a wire following a tether line to the White House across the street.
It's also worth noting that while not used in this context here the term "telegraph" dates back far further than its use with the electrical telegraph which was first demonstrated by Wheatstone in 1837. The term telegraph was used as early as the late 1700s to describe visual telegraphs which used various visible signals (think semaphores) to transmit information.
^1 As a sidenote I really hate it when people refer to Wikipedia as "wiki". There are many wikis out there. Wikipedia is just the most well known of them. Your usage isn't entirely wrong since you refer to an article in a wiki, but just wanted to point that out.