Author Topic: information on British thompson houston carbon bulbs  (Read 2184 times)
Rrdd123
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information on British thompson houston carbon bulbs « on: August 08, 2017, 11:25:19 AM » Author: Rrdd123
Hi all

I am new to the forum having come across you whilst researching two bulbs I bought at a car boot sale (swap meet) They are marked 8  240 BTH carbon. They both work.

I would appreciate any information including a possible date, (The test equipment they came with is 1950's but I am sure the bulbs are much earlier.) and as I intend to sell them your opinions on value.

I hope the photos come out ok. I had great trouble downsizing the file size to meet the 2048kb limit.
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Roi_hartmann
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Re: information on British thompson houston carbon bulbs « Reply #1 on: August 08, 2017, 04:49:17 PM » Author: Roi_hartmann
Welcome to the LG.

I'm not any expert on dating old incandescent. You might have downsized those photos little too much as it hard to make out any details in the photo.

What I could see thou is that these have those things(sorry, don't remember the english name) atop of the lamp that was used to pump the air out and that usually means old lamp. I do remember hearing that those "pump tubes" were passed out in 1930's or so but this is just me guessing. Maybe James or Medved can tell you more about these.
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Aamulla aurinko, illalla AIRAM

hannahs lights
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Re: information on British thompson houston carbon bulbs « Reply #2 on: August 15, 2017, 03:04:28 PM » Author: hannahs lights
Hi the thingy you refer to called a glass pip yes its were they pump air out then pinch it closed don't know how its done but thats what its called
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