In the late fifties to increase capacity for buses the idea of 1 1/2 deckers occurred in Germany. The reason was that articulated buses and trailers were not permitted and true double deckers were in general not feasable because of their height. The back end of an 1 1/2 decker was similar to a low floor double decker while the front end was a standard single decker. As far as I know Ludewig was about the only body builder that built such buses.
The picture shows an 1 1/2 decker adapted to the standard requirements
of VÖV (Verband Öffentlicher Verkehrsbetriebe, the union of
public transport companies) as codified in 1966.
Ludewig built them from 1969 until the mid-seventies.
London has also had its 1 1/2 deckers, but they were not built
to increase capacity for passengers.
This picture shows one of the batch of eight 1 1/2 deckers
(C 106 - C 113) London Transport introduced in 1936 for
London Interstation service.
They had an extensive luggage compartment below the raised rear part.
They saw service until 1950.
This is an 1 1/2 decker purchased by London Transport on behalf of British European Airways. The design is similar to the bus shown above, although the roof was made higher over the front part. They were used to provide service from Gloucester Road to London Airport, and entered service in 1952/53. They are now withdrawn (around 1966/67?).
Although formally of class RF they never got a number
in that range as they were owned by BEA.
These were buses from the RMF class, again purchased by LT
on behalf of BEA, with numbers BEA 601-665.
They entered service in 1966.
The smallish odd-looking trailer is (of course) for luggage.
These too are withdrawn by now (when?).
When buses grew longer in the twenties it was thought in Amsterdam that they would give problems with the high hump-bridges in the city. To enable easy negotiation of such bridges an articulated bus was designed. Three of them were built in 1924, and almost all photographs I have seen of them picture them on such a hump-bridge.
Alas, the idea was perhaps good, but it did not serve.
The articulation was unreliable, and most bus-routes did not pass such
bridges.
In 1927 the three buses received a rigid chassis.
This picture shows an Dutch articulated bus from 1924.
Contrary to the bus from Amsterdam, this one has a more normal appearance.
I do not know how many were built, where they did run, etc.
This foto shows an early postwar articulated bus in Freischütz, Germany,
in 1954.
Although the bulbouse nose had gone out of the picture for nearly all buses
except touringcar, this one still had it.
Because of the extreme shortage of buses in the Netherlands after WW II
(almost no working bus remained in the Netherlands), quite a few vans
were rebuilt into buses.
They ran from about 1944 for a few years.
The second group of emergency buses had trucks from Crossley (UK) and trailers built by DAF. There were 240 trucks and 250 trailers. They ran until the late fifties, although in the later years they were not used in normal operation. (I remember having sat in one on a school trip as a boy.)
At one time this kind of bus was not so very exceptional, and indeed I
have a book that contains a much older photograph of such a bus in
Antwerp, Belgium, alas, that photograph is extremely unclear.
Although advertised as a double-decker this is not really one. Most remarkable is the lay-out of the windows.
Inside this bus had compartments alternating on the lower and upper floor.
One reached those compartments by either climbing down or up from the
gangway in the middle.
London had its famous double deckers (although I do not really understand it, there have been many more cities with double deckers), Paris was famous because of the buses with an open balcony at the end where you entered and left the vehicle, in most cases in the middle at the rear end.
Here we see an old version of such a bus (they actually did run until
1971).
But this one has another interesting feature, it has three axles with
a steering rear axle (as can be seen if you look closely).
This is one of a batch of 51 "Schreiner H6", a longer version of the
very successful (1269 "Schreiner H") standard series.
This version was introduced around 1920.
To stress its impact, here a photograph of an open balcony of a Paris
bus.
The conductor is just giving a signal to the driver.
When the open balcony buses were retired in 1971 there was a huge
outcry.
By 1976 the Paris municipal transport authority introduced a new batch
of buses with open balcony, but this time they could only be entered
from the inside.
And I must say that the times I was in such a bus the balcony was
pretty crowded, and not only by tourists.
These buses were commisioned by the Dartford Tunnel Authority to carry
bicycles through that tunnel.
The batch consisted of TT 1-5, and entered service on
18 November 1963.
Service was already replaced on 31 October 1965, due to lack of traffic,
by Land Rovers, operated by the Tunnel Authority.
The lower floor was for bicycles, passengers could sit on the upper floor.
There were special platforms to enable the passengers to enter the bus.
A similar service (with trailers for bicycles) has been operated in
Amsterdam during a short time, but I have not yet been able to find
a photograph of such a combination.