
The Lamp That Saved Coal Miners' Lives - Hooke
http://mentalfloss.com/article/71969/show-tell-lamp-saved-coal-miners-lives
======
hoppi
It is sad reading the impact section at
[https://en.wikipedia.org/wiki/Davy_lamp](https://en.wikipedia.org/wiki/Davy_lamp)

"The introduction of the Davy lamp led to an increase in mine accidents, as
the lamp encouraged the working of mines and parts of mines that had
previously been closed for safety reasons."

and

"Another reason for the increase in accidents was the unreliability of the
lamps themselves. The bare gauze was easily damaged, and once just a single
wire broke or rusted away, the lamp became unsafe. Even when new and clean,
illumination from the safety lamps was very poor, and the problem was not
fully resolved until electric lamps became widely available in the late 19th
century."

Seems like it wasn't as successful as it is made out to be in this article.

~~~
TeMPOraL
An extreme example of
[https://en.wikipedia.org/wiki/Risk_compensation](https://en.wikipedia.org/wiki/Risk_compensation).
I was somewhat disturbed when I first learned that this is what actually
happens.

------
po
I don't understand how a methane/oxygen reaction, once ignited, cannot travel
through a metal cage… I'm sure it works but the "absorb the heat that caused
the explosions" explanation doesn't make sense to me. Does anyone know in more
detail how this works?

~~~
cma
more details here:

[https://en.wikipedia.org/wiki/Flame_arrester](https://en.wikipedia.org/wiki/Flame_arrester)

[https://en.wikipedia.org/wiki/Davy_lamp](https://en.wikipedia.org/wiki/Davy_lamp)

[https://www.youtube.com/watch?v=u-GeraWUP6E](https://www.youtube.com/watch?v=u-GeraWUP6E)

The wire mesh drops the temperature below ignition temperature and also drops
the pressure. Since the outer air remains relatively cool, the mesh presumably
continues to shed some heat through contact with the outside air, and so
doesn't itself reach the ignition temperature on the outside. Maybe sort of
like how you can hold a flame to a paper cup full of water and even though the
paper is dry on the outside, it won't catch.

------
jgrahamc
Sir Humphry Davy (the inventor of the lamp) had an awesome honeymoon:
[http://blog.jgc.org/2008/09/ultimate-nerd-
honeymoon.html](http://blog.jgc.org/2008/09/ultimate-nerd-honeymoon.html)

------
nateguchi
_The chemist received a medal from the Royal Society and was made a baronet;
he even “designed his own coat of arms, showing the safety lamp encircled with
a Latin motto which announced: ‘I Built The Light Which Brings Safety.’”_

Excellent!

------
gambiting
From the article on Wikipedia:

"The introduction of the Davy lamp led to an increase in mine accidents, as
the lamp encouraged the working of mines and parts of mines that had
previously been closed for safety reasons"

