Not so much household

[keithinuk]

I little thing I picked up today, it's made by Griffin & George Ltd, its a little coil setup. It's a nice curiosity piece, I don't think its all that old, but still a nice toy and still works.

[McMurdo]

Probably from a school, that is what Griffin & George were into.

[wireful3]

I agree. It looks like a demonstration induction coil. The sort of thing that was supplied in the 1930s. Perhaps it was used along with a Wimshurst machine to show how high voltages could be produced.

Are there insulated handles on the rods? Adjusting them for maximum spark while running might entertain the class.

[Peter.N.]

Its obviously been kept dry!

Peter

[Herald1360]

Originally Posted by wireful3

Are there insulated handles on the rods? Adjusting them for maximum spark while running might entertain the class.

I'd be inclined to run it on floating battery power and just tweak one rod!

[mike_newcomb]

Hi Keith,

Griiffin and George are now part of Fisons Scientific. Suggest email them a photo or two asking if they can provide any details including, year, price etc.

McMurdo is correct in that they supplied schools with scientific equipement.

I worked for quite a time in the G+G computer department when they were at Park Royal.

Please advise back on progress.

Goods Luck - Mike.

[julie_m]

I remember the name "Griffin & George" from my school's science labs. Beautifully-made equipment, all polished hardwood and gleaming brass, which conveyed an impression of scientists taking immense pride in their work.

Your coil is a fantastic piece. Does it have its own interruptor, or does it require an A.C. supply?

[keithinuk]

Thanks guys, it's in pretty good condition. I was told it runs off 6v, as I have some small 6v gel batteries about; they work it fine.

The little controllers on the bottom left have a knob missing and they should be strapped together so they move as one, but it has not wired to them inside.

I will have to find some wiring information and put it back to fully working order.

All the brass parts seem to have a red coating to them, maybe some type of lacquer, so may leave it as is, rather than polish anything.

It has its own adjustable interrupter.

A better picture for you.

[Herald1360]

Originally Posted by ajs_derby

Does it have its own interruptor?

See pic- the interruptor is pointed at by the red line.

[ekcopyephilips]

Is it some sort of surgical diathermy or hyfecator ? These used to have spark gaps that needed setting up well into the 1970's

[keithinuk]

No, I think its just a school display model, the company was well known for this type of science display equipment.
It's not a top end model of the Ruhmkorff coil but it was a nice cheap boot sale find and I think I will just clean it up and put it back as it was originally, as it is essentially a display model.

http://www.museumoftechnology.org.uk/expand.php?key=690

[Ed_Dinning]

Hi Keith, the swivelling contacts were used to reverse the primary supply and possibly as an on/off switch.

Ed

[keithinuk]

Only asking as I don't know, what would reversing the primary supply do?

[Breton56]

When I worked in a COFE most of our physics and chemistry equipment came from Griffen and George. We needed a new kettle for our tea breaks-this was ordered as a steam generator. Completely irrelevement to the thread but just a light-hearted comment.

[Ed_Dinning]

Hi Keith, it would alter the polarity of the output terminals; possibly useful in sone physics experiments. I know the one at our school had this facility as well (but I don't think it was ever deliberatly used)

Ed

[OscarFoxtrot]

The Science Museum have quite a collection of Griffin & George stuff

http://collectionsonline.nmsi.ac.uk/...=3539&t=people

[JBRobinson]

When I was at school in the early 1960s there was a spate of my fellow pupils bringing in somewhat similar (but minus the fine woodwork) 'shocking machines' for their evil pleasure rather than our edification. Having never seen one before I was 'got' only once - once bitten twice shy - but thereafter I was quite happy to encourage others to experiment!

[paolo]

I had one of those shocking machines in the 70s. Very similar to the device pictured in this thread but with two silver tubes that the victim - sorry - willing participant would be asked to hold on to. Once cranked up, the willing participant was unable to release his or her grip causing much mirth and hilarity for all (actually mostly just me).

I think it was powered by a 9v battery but it may have just been a C or D cell.

Doubt such things would make it out to children these days!

Paul

[broadgage]

Originally Posted by keithinuk

Only asking as I don't know, what would reversing the primary supply do?

Reduce or even out the wear on the interuptor contacts, as well as reversing the output polarity.

[kalee20]

Originally Posted by Ed_Dinning

...it would alter the polarity of the output terminals; possibly useful in sone physics experiments...

...such as cold-cathode discharge tubes - you can see the bands and dark spaces change positions from one end of the tube to another. Or the sort of asymmetric tubes with things like fluorescent ends, or Maltese crosses in, which are polarity-critical.