The Aladdin model 9 lamp introduced entirely new fonts while retaining
a slightly refined version of the model 7 burner and model 8 wick raiser.
This design carried through models 10 and 11 with a few variations.
The burner base and outer wick tube used on models 9, 10
and 11 remained the same as the model 7 and 8 burners. The
model 8 wick raiser was also used unchanged. There were minor
changes to the construction of the flame spreader and gallery
from the earlier lamps.
The model 9 was in production for two years and was sold
concurrently with the model 10 during the second year.
There are two versions of the model 9 lamp. The early version
has the model 9 designation below the diagonal Aladdin logo
on the wick raiser knob and the table font has a wide flat
bottom flange in the model 6 style.
The late model 9 version, like the models 10 and 11 have
the model designation over the diagonal Aladdin name and a
table font that has a narrower crimped foot flange.
The early model 9 used the same mini wick holder that was
used on the model 8. The mini wick holder disappeared with
the introduction of the reinforced wick that has built in
mounting tabs. This appears to be around or just a little
before the time when the model 10 was introduced.
The model 10 and 11 lamps are basically identical in design
to the late model 9 making them essentially marketing "upgrades"
and not technology upgrades.
I would guess that the early model 9 style was in production
during the first year and the late style was in production
during the second year when model 10 was concurrently produced.
Brass model 9 London wick raiser knob