Click! How the lights go on
We have had electric light in our homes for more than a century. The light switch and the light bulb now seem inseparable.
LIFE Photo Collection
The first practical electric light bulb was developed in about 1880 by the American inventor Thomas Edison.
In the years that followed, more and more cities installed a power grid. At first, many houses had only one electrically lit room.
Of course, a light does not need to be on all the time. To turn it on and off, Edison included a rotary switch in the light fitting.
A rotary switch worked well for a single light bulb, but a lever or knife switch was more common to turn several lights on and off at the same time. This worked by pulling a lever up or down.
One problem with early switches was that sparks could fly if you moved the knob or lever too slowly. This rotary switch, patented by John Holmes in 1884, solved that problem. It has a spring system, which ensures that the light is turned on or off immediately.
Miscellaneous switches (1920/1929) by unknownNEMO Science Museum
The rotary switch had some advantages: it was safe and there was no way it could come into contact with live parts, as was the case with the knife switch.
Table lamp (ca. 1900–1902) by Pierre-Adrien DalpayratThe Metropolitan Museum of Art
Another early type was the pull switch: the light goes on or off when you pull a cord. This 1900 table lamp has several of these cords.
Miscellaneous switches (1920/1929) by unknownNEMO Science Museum
Eventually, another type became the standard: the wall-mounted toggle or tumbler switch.
Even in the dark, this is not hard to operate.
Rotary switches are still used in some places, such as on ships and in factories. There, toggle or rocker switches are too easy to turn on or off by accident if you bump into them.
It is striking how many different materials have been used for switches over the years.
Porcelain was common in the early days.
More elegant houses had metal, ...
...and in the 1920s the brownish-black plastic Bakelite was widely used.
From the 1960s onwards, other plastics came into use and the design also changed. Most of the parts and the wiring are now fitted in the wall rather than mounted on it.
Power sockets are often found close to switches, and over the years they have followed exactly the same trends in materials and positioning.
Miscellaneous plugs (1925/1970) by unknownNEMO Science Museum
Many countries had their own socket designs until the 1920s.
The Netherlands, along with much of the rest of Europe, eventually adopted a standard type originally developed in France.
This kind of standardisation did not extend much further than continental Europe. Around the world, there are no fewer than 15 different standards for power sockets.
When it comes to light switches, though, the world is united: the rocker switch is now the international favourite.
Object of the Month – December 2021
Each month, NEMO Science Museum spotlights one item from its collection of 19,000 special objects. These objects, which were once part of people’s everyday lives, show us how technology changes over time.
This story was written with the help of the Museum of Industry in Ghent.
