Why is it called a Bubble

[BobB]

Today is a public holiday in South Africa (reconciliation day so we have some friends around. Showing a non (model) railway person my new Dapol class 121 I called it a "Bubble", the name which we applied to the 121's and the 122's.

Immediately the conversation turned to how did it get that name. In fact the question was how could such a small train have been given a name at all. Thinking on my feet (actually I was sitting) I suggested that the train was the smallest and it was christened after the smallest cars on the road, the bubble cars.

It had the effect of deflecting the question because we had to describe the bubble cars of the time. But is this why the trains were christened ?

[poliss]

The Goods and Not so Goods website says it's because of their extensive glazing.
http://www.igg.org.uk/gansg/00-app3-4/ap3-dmu.htm

[Newportnobby]

Wickedpedia doesn't seem to know the reason, although there is a picture of one in NSE that will make Tank happy.
http://en.wikipedia.org/wiki/Class_121
I always remember that us spotters used to call the early DMU's 'bog carts'. I don't know why 'cos they never had one on the ones I travelled on.

[edwin_m]

Is it a reference to the (road) cars that were briefly fashionable in the 60s? 

http://en.wikipedia.org/wiki/Bubble_car

[Jerry Howlett]

Don't think its ref to the cars as like NewportN I was train spotting in the 60's - 70's and called them bog carts. I worked at Swindon loco (ok it was just a one road tin skack by then) in 1974/5 and never heard the term. I wonder if it came about after they were used for route learning. Overtime etc was always "bubble" . Your views especially any real train crew out there ?

[Mustermark]

I always remember that us spotters used to call the early DMU's 'bog carts'.

That's funny... I'd forgotten that. I now recall calling them both bog cart and bog unit.

[thos]

We called DMUs 'bug carts'.

[Donkey]

Wickedpedia doesn't seem to know the reason, although there is a picture of one in NSE that will make Tank happy.
http://en.wikipedia.org/wiki/Class_121
I always remember that us spotters used to call the early DMU's 'bog carts'. I don't know why 'cos they never had one on the ones I travelled on.

We called them boggies up here in Teesside, no idea why though 

[EtchedPixels]

Also historically 'Widowmakers' - because in their early days they were deployed to try and make closing lines profitable so their appearance usually heralded a closure.

Not sure where bubbles came from, possibly from the railbuses ?

The Butetown bubble still seems top be going in Cardiff though. I think its a plot to increase patronage