In a Nutshell
I wish you will have so much fun in using this machine as I had in studying it during my short ownership

Introduction:
The life of Willgodt Theophil Odhner [1845-1905] and his inventions are very well documented (ref.1). In 1875 he invented his "Arithmometer", a versatile calculating machine. Driven by its technical director Franz Trinks, the German, Swiss and Belgian licenses were bought (for 10'000 Deutsche Mark) by Grimme, Natalis & Co., in Braunschweig, Germany in 1892, who presented the machines at the 1892 World's Fair (400th anniversary of Christopher Columbus) in Chicago. Advertized as a "Gehirn von Stahl" (brains of steel) the machine was said to familiarize with its new owner within 10 minutes (see also pict.s 25,26). Grimme, Natalis & Co., was renamed "Brunsviga Maschinenwerke AG" in 1927. The Trinks-Brunsviga 1910 model MA pinwheel calculator is highly collectible and quite valuable, since it is a miniature "Midget" version of model A , also called the "Brunsvigula" and has 18 result digits, instead of model B's 13 digits. There were only 3342 machines built, my machine with serial number 26'912 is from early in 1914. The price was 600 DM in 1910, that was about a 10 month's income of a skilled worker. There are numerous operation guides, owners manuals etc. on the internet (free), most of them in German. It is recommended to study these manuals, since they contain tips and tricks, how to accelerate your calculations, that have been developed over a long time by the zillions of users. It were in fact Brunsviga sales representatives, who were trained in speed calculations, and when they didn't hurry, they were fired. Would you believe you can calculate sqrt(455.993316) with full accuracy (5 digits), within one and a half minutes?

Additional information:
ref.1: http://www.crisvandevel.de/bvex.htm
ref.2: www.rechenmaschinen-illustrated.com/timo%20leipala.pdf and .../timo%20leipala_Odhner_Part%202.pdf
ref.3: http://home.vicnet.net.au/~wolff/calculators/Brunsviga/Brunsviga.htm
ref.4: http://www.rechnerlexikon.de/artikel/Brunsviga_A
ref.5: http://www.vintagecalculators.com/html/operating_a_pinwheel_calculato.html
ref.6: http://www.rechenmaschinen-illustrated.com/pdf/Trautschold_part1.pdf, and parts 2 and 3
ref.7: https://www.youtube.com/watch?v=rLblrD825ew&feature=youtu.be

About my Machine:
The machine is in exceptional condition, with the wooden cabinet having only very few and almost invisible scratches. The key escutcheon was missing when I got it, and I made a true-to-scale replica by hand with even engraving the original garland artwork you see in pict.27. The chassis was taken apart, thoroughly cleaned and lubricated with Singer sewing machine oil. It has a little wear of the black paint near the most used lever area, and the various decals are readable but not perfect. By comparing the machine to other instances of this rare model I classify the condition as excellent or near mint. After familiarizing with the machine (it took me more than 10 minutes) I made a youtube video (ref.7 or click on thumbnail 28). Please e-mail me (Kris) for any questions, ich spreche Deutsch, je parle Français.

For the techies only:
Too many techies to even start. Please google "brunsviga" and you'll find it all

Here are the specifications:

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