Having studied all catalogues from Optimus available at CPL I see a connection between the telex codes used for ordering and the later letters to be added to certain models (I have listed these codes on my website). The Optimus 100, for instance, could be ordered as Nalle or Nelma, depending on wether you wanted it without or with a gauge. Later, the 100 N was launched. The Optimus 200 could be ordered as Opett, Ettma, Opben, Benop - the significant letter here (though not 100% consistent) being the P, and later a 200 P was launced. Similar for the model 300. Well, I know that these letters have been discussed before but as I read it, without any conclusion. Could there be something in what I suggest? The G is the obvious Gauge-variety, and the A simply the wide-globed variety table lamp. Which other models with a letter exist? Do they match the pattern? And, btw., I cannot see the N and P models listed in the catalogs. Where can I find out when each of them was introduced and again dismissed?
When the N and P models were introduced and finished is a lot easier than knowing why they were there. This variation was introduced in the late 1940s and continued until 1956/57. The only difference I have found is where the vaporiser attaches to the valve block (for lack of a better description). Here the previous variations had a narrowing of the diameter of the vaporiser tube. The P models had a straight tube and therefore a larger nut. This would have given fewer steps in production and thereby a cost saving, but otherwise I can't think of a reason for the change.
Thank you - dating is important for many reasons. The reason for the models being there could be (just a theory) that they saw a decreasing sale and wanted to introduce something with a new name, giving the impression that the lanterns had now been improved. A marketing stunt, simply. To back up the stunt technically they changes a few details, and the less expensive production process that you mention could easily have been part of the idea. But for the names - could my suggestion make sense? It would be typical marketing thinking to just add a letter symbolizing the nick name of the thing, thereby speaking to the customers as kind of friends (or fans) of the manufacturer, knowing what this little letter symbolizes.
It's as good a theory as any. I doubt we will ever know why they chose N and P as no documentation has ever turned up.
