How do we know?
↻ One of the pages with a moving picture
The first long-distance voice call was made over a wire in 1876.
- You talk. The microphone picks up the vibrations of your voice and turns them into electricity.
- The phone’s computer turns your message into binary code, a string of 0s and 1s.
- The phone sends it as radio waves through the air to the nearest cell tower.
- Towers pass it along, often through underground cables, to the tower closest to your friend.
On 10 August 1876, voices spoken in Brantford, Ontario, reached Alexander Graham Bell in Paris, Ontario, 13 km (8 miles) away, travelling by wire.
In Bell’s own words, it was the first time a voice traveled over a telegraph line between telephones that were miles apart.
That 1876 call was one-way: he could hear, but not answer.
Wow number
01101000 The letter h in binary code. So “hi” is 01101000 01101001.
Myth or fact?
Places with cell coverage are divided into areas called cells. Fact. Each cell has a cell tower in the middle.
Phone messages travel only through the air. Myth. Between towers, they often zoom through cables buried underground.
Think about it
Bell’s 1876 call was one-way: he could hear, but not answer. What would you need to add to talk back?
Where in the world?
Brantford, Ontario, Canada where, on 10 August 1876, voices spoken here reached Alexander Graham Bell in Paris, Ontario, 13 km (8 miles) away — 43.1394° N, 80.2644° W.
Where these facts come from
Every number on page 95, and who measured it
This page tells us how phones turn messages into 0s and 1s and send them to cell towers.
How do cell phones work? — Ask Dr. Universe, a science-answers site from Washington State University
askdruniverse.wsu.edu/2025/08/14/cell-phones-work
We checked it on 31 October 2026
This page tells us that on 10 August 1876 voices travelled by wire from Brantford to Paris, Ontario, a distance of 13 km.
Milestones:First Distant Speech Transmission in Canada, 1876 — IEEE, a big group of electrical engineers, which marks famous moments in invention history
ethw.org/Milestones:First_Distant_Speech_Transmission_in_Canada,_1876
We checked it on 5 November 2026
This page tells us about Bell's one-way call on August 10, 1876.
The Bell System - This Month in Business History — The Library of Congress, the U.S. national library
guides.loc.gov/this-month-in-business-history/august/bell-system
We checked it on 31 October 2026
This page tells us about Bell's family home in Brantford and how sound is a vibration.
History — The City of Brantford in Ontario, Canada, home of the Bell Homestead
brantford.ca/things-to-do/arts-and-culture/museums-and-galleries/bell-homestead/history
We checked it on 31 October 2026
This page tells us how a phone's microphone and radio waves work.
How do cellphones work? — Explain That Stuff, a science-explaining website by writer Chris Woodford
explainthatstuff.com/cellphones.html
We checked it on 31 October 2026
Has this changed?
How phones carry your voice is not going to change in the basics.
Phones themselves keep changing fast, and what is built into towers and networks changes too.
Words from this page
- binary code
- A way to write messages using only 0s and 1s.
- radio waves
- Invisible waves that carry messages through the air.
- cell tower
- A tall antenna that sends and receives phone messages.
Try it!
Send a message in binary.
1. Agree with a friend: a clap means 1, a tap on the table means 0. 2. Send “hi”: 01101000, pause, 01101001. 3. Your friend writes down each 0 and 1, then checks the code.
What happens: you sent a message in 0s and 1s, a bit like your phone does with radio waves!
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