Alexander Graham Bell s Telephone Prototype The Genius Of Invention Earth Science

The telegraph network alerted the world to the benefits and opportunities of global communication. But the technology had gone as far as it could. If we were to be truly connected, what was needed was a form of telegraph which could do more than just transmit dots and dashes. We needed something that could carry the full majesty of the human voice. We needed the telephone. Yes, the telephone, an invention cloaked in controversy. And we're going to look at the work of the man most famously associated with it, Alexander Graham Bell. Now, in the 1870s, electricity was cutting-edge technology. And Bell and his assistant Watson, well, they were young men in their 20s and they wanted in on this cool new technology. And telegraph was here, that could send messages. So what else could they send via this new technology? Well, they thought, human speech, why not? But how would you do it? You've got to turn the human speech patterns into an electrical pattern that exactly matches it. And nothing existed at the day that could do that. So they knew they'd have to invent it. And they weren't the only ones working on this. In the end, this contraption here, which looks very odd, is a replica of one of their first goes at the problem. It's called a liquid telephone. And it involves a cone which goes down to a membrane. Now, when you speak down the cone, the membrane vibrates. And that's connected to a needle which is dipped in acid. When the parchment vibrates, the sound of your voice, that changes the depth of the needle in the liquid and changes the current being transmitted. So in theory, it should be able to give you that continuous variation in current that you need in order to mirror the human voice. So we've connected this up to an oscilloscope to see if that actually does work. Let's see. It's actually not bad. And it's, you know, you get something out of it. And that first recognition must have been really promising. But although it looks like an electrical signal, it doesn't, perhaps, we haven't proved that it sounds like one. So now what we need to do is connect this into our sound system. And Paul, our sound guy, is doing that right now. So if I speak through this system, the question is, can he hear it? You ready? Hello, hello, hello, hello. I could definitely hear something. It's not very clear. That is just incredible that something so rudimentary like this can do that. It was crazy. It was weird. But it worked. And it was the start of the telephone. But it's not practical to have a liquid transmitter having acid just sort of sloshing around in containers. It's dangerous. So Bell did what good inventors do. He tinkered and he made incremental improvements until that prototype had been turned into a fully functioning system for transmitting voice over a wire. It was called the centennial phone. And this is how it works. Now, the sound waves travel in through the mouthpiece, hit the diaphragm, which vibrates, and makes contact with an electromagnet inside an iron cylinder. This turns the vocal vibrations into a changing electrical signal, which flows through the wire to be turned back into sounds at the other end. This formed the basis for how telephones would work for the next 100 years and introduced one of the greatest revolutions in communications history. Bell patented his work under the bracket improvements in telegraphy. And although the phone itself would take years of refinement, a little over a year later, the Bell Telephone Company was born.