Recently purchased a, a few days ago, a “nach Meyer” flute made by Wihelm A. Johnsen Christiania. I was perfectly aware of the dangers of buying such a flute. As it turns out, I was quite fortunate. It is a nice flute for the “German” type, no cracks or repairs, plays at 440 throughout and has been well cared for. It has 11 keys and, of course is made of Blackwood, and a B foot. I would like to find some information on this maker; perhaps someone could direct me to a source.
Don, I’m pretty sure we’ve come across this maker or dealer from Oslo before on this forum. Maybe the search tool…? And I’m sure Langwill holders will check up for you. Good news on the playing pitch’ then. 
Sorry, nothing in Langwill.
My recollection from another board is as follows. Wilhelm A Johnsen was most likely a dealer or re-seller of instruments. Christiana is very likely the location of his dealership. Kristiana or Christiana was the name of the city we know today as Oslo during the period that the flute was sold. So from that we might conject that the flute is a nach Meyer type of flute, probably German in origin, sold in the later 19th century in Oslo, Norway.
Photos?
Hope that is useful to you.
Feadoggie
Feedogie: makes a lot of sense. I have included some photo’s, my first try at such an endeavor, hope they turned out okay. Thanks to all for the feedback.
AHA!
Just given this a little surf time… First, looks like my recollection of a previous online encounter was with this very same flute on Earlyflute a couple of years ago.
Second, Google finds various things, like & primarily this in the Norwegian Biographical Encyclopedia (I used Google translate from the Google search). Seems Wilhelm Johnsen/William Johnson was the same person as William Farre (changed name in 1915) and that he was a shop-owner and dealer (amongst other things), not necessarily a maker, though the article refers to his business having workshops. Also his dates (b1874-d1950 and starting in retail in 1896 and going bankrupt in 1925 though with some ongoing activity thereafter) would push this flute firmly back into my usual suggested period bracket for the bulk of nach-Meyers of c1870-c1940! (He was also something of a folklorist/collector.)
I also found this link mentioning Farre in these terms “The last two photos below show an Eb soprano Swedish cornet made (or at least sold originally) in Oslo, Norway by William Farre in the 1930s. Farre was known to be a dealer and likely had instruments made to his design in Germany.”
It seems the Christiania spelling of Oslo’s then-name continued in popular use well after the official change (in 1877, so in WJ’s infancy!) to Kristiania, so no useful dating evidence on that score from the stamp. We don’t thus far have any evidence as to which form of his name he used as a stamp at what period, so that doesn’t allow for clear dating either - he may well have carried on using pre-existing stamps at least for a while after changing his name to Farre in 1915, but if it has any applicability/reliability, it does tentatively suggest a pre-WW1 origin for the flute. We also still can’t determine whether he was having flutes built in his own workshops or importing them from Germany. I guess we’d need a Norway based researcher with access to trade directories and journals and advertisements and maybe even company records from the period to learn more.
So, there we have it for now. A (very) late C19th or early (1st 1/4) C20th flute, probably made/sold between 1896 and 1915, possibly made in either Norway or Germany, the latter marginally more likely on evidence to date.
Langwill had very little on William Farre. Brass Instruments, flourished Oslo 1896-post 1950. Dealer, music publisher; a helicon reported. That’s it.
Wow!!! many thanks to all for the information and time involved. Jem, I think you’ve hit it right on the head, makes all kinds of sense. Frankly, I just don’t know where to begin in terms of thanking you. Your assistance has proven invaluable, not only do I have a nice flute that plays well (440!!!) through the 3rd octave (based upon your suggestions on hold and use of keys to vent), I also have the provenance. It may not have the Irish sound that we love, but I’m having a blast learning about it and playing it! It’s like Christmas in July here at my place. In addition, my chops are tightening up and the breath control is in the process of improving. 
Thanks many times over.