I make machines talk to each other so that people can talk to each other through the machines from really far away. Like, you know that brand new thing called the telegraph? Well now we call those optical telegraphs because ours are made of pieces of lightning called electricity, and I work on even better versions of that. You can talk to anyone you know instantly with the machines I work on, no matter where in the world they are.
Optical telegraphs, also called semaphores, were invented in 1684, and first experimented in 1767. The most popular system was invented in 1792. There are a lot of hills around the US and Europe named “Telegraph Hill” because they used to be where an optical telegraph station was set up.
You’re thinking of the electric telegraph, which was indeed invented in 1837, and very quickly supplanted optical telegraphs. We now use the term telegraph almost exclusively to describe the electric telegraph, but someone from the 1700s wouldn’t know that.