Old Tech thread

Back in mid seventies I was a trainee in a UK coalmine. In one area of older workings there was a row of lights giving off a strange blue glow.
As far as I recall each light had an enclosed turbine/dynamo that was powered by compressed air.
I remember some old collier saying they'd been operating since the fifties in that area.
Might be one of these, @Danny McG:

Compressed air lamps​

Compressed air powered lamps were designed for use in gassy mines. The lamp is powered by compressed air, which drives a turbine wheel contained within the lamp body. The turbine produces electricity to power the lamp bulb. These are for use in mine transport and fixed installation. Not much info on the page it might be a a lead?
 
It can't be a lead: the whole point is that the electricity was generated inside the lamp body....

;):)
Not sure about that, Ursa Major... The article says the lamp is powered by compressed air, which drives a turbine wheel contained within the lamp body [that] then produces electricity to power the lamp bulb. Danny McG says "As far as I recall each light had an enclosed turbine/dynamo that was powered by compressed air". Where do you see a contradiction?
 
That's just one of Ursa's puns.

They are safety lamps - the modern day equivalent of the Davy Lamp as the article says.

I don't understand exactly how they work, but the electricity is enclosed to prevent any spark or heat, resulting in the ignition of any Methane (aka marsh gas, swamp gas or bog gas.) There is a lot of heavy machinery working in mines, so cables on walls or on transport could get damaged and wires frayed.

But why is it "a strange blue glow"? Is that some kind of safe filament or fluorescent tube too? Wouldn't any enclosed lamp be as safe as any other?
 
Here's a classic bit of old tech, my wife spotted this fridge from 1956 online not long ago.
She's very enamoured of it and keeps saying she wants one!

Short video, just over a minute:-

 
Last edited:
Here's a classic bit of old tech, my wife spotted this fridge from 1956 online not long ago.
She's very enamoured of it and keeps saying she wants one!

Short video, just over a minute:-

I can see where she is coming from.
 
I remember the refrigerator from when I was a kid.

Even the ice cube trays were built like tanks.
 
Last edited:
Judging from the price CDs are in our local charity shops - one I frequent sells CDs five for a pound, another four for a pound, and they both consider anything that looks like a box set to be a single item. I think a lot of people would agree with you.

I buy a LOT of CDs.
But I'm getting ready to pre-order a forthcoming set of Bob Dyland CDs for about $140.
 
An idea seriously put forward to increase the safety and numbers of cross-Atlantic flights in 1929...
2901_fc1.jpg

29010002.jpg

29010003.jpg
 
Interesting read (and idea), @Pyan. I assume it was never developed because it was anticipated that the rate of aviation advance would soon make the scheme redundant.
 
edit: Reading the small print I see that they say "floating". So I removed the comment.
I am reassured that the structure has been tested on a pond though.
:giggle:
 
Last edited:
I rather like the anticipation that each one will cost about £300,000 - less than a 2-bed semi in Slough. Mind you, allowing for inflation, that £300k is about fifteen million pounds today, or a 6-bedroom house in Fulham. o_O
 

Back
Top