Wilhelm Collath was born in Greifenberg, Pommeren( http://en.wikipedia.org/wiki/Gryfice ) on February 25th, 1838, which was the same year that Georg Teschner founded his firm in Frankfurt an der Oder.
In 1858 Wilhelm Collath began his walkabout and he may have begun in the Danzig area. By 1859 he was employed in the Teschner shop and 11 years later in 1870 he was a partner as well as became a member of the Frankfurt an der Oder gunmaker's guild. Sources give that in the 1890s Wilhelm Collath purchased the Teschner firm. Johann Nikolaus von Dreyse may have laid the foundation with his needle-fire gun and Teschner & Collath built on his design with Berger of Köthen in the mix somewhere. The action is typically referred to as the Collath or Teschner-Collath action. Wilhelm Collath had at least 8 weapons patents with 1 being a needle-fire type patent. His design was an "eccentric" lockup with a tipping barrel breech and really no hinge pin. When the horn underlever is moved to the left, the tubes move forward and then up with the forend/receiver acting like a trough. Evidently Collath, etal, really believed in the action as they didn't really deviate from it and were about the only ones offering it. Even though they sourced other craftsmen, which just makes economic sense, they were makers to the trade. Around 1900 the Teschner-Collath firm was churing out 1000 examples per year and by 1906(Wilhelm Collath expired on June 21st of that year) there were around 100 craftsmen employed for the effort. But from marks on Collath examples, it appears that the firm sourced the craftsmen at Zella-Mehlis as well as Suhl. Seeing your example has "TESCO"(TESchner-COllath) I'd say it passed thru the Frankfurt an der Oder proofhouse, which used Troisdorfer powder and closed in 1939, post 1912 and pre-1923. It just may have been made in the post WWI - 1923 period. Georg Teschner had some odd cartridge designation where a 10 bore was 0 and a 28 bore was 8. It seem to catch on in parts of Europe. Teschner-Collath was in the cartridge development and I'd say most of their examples would only accept their proprietary cartridges. Many times on the sides of the barrel lugs the calibre or number will be stamped there.

On the safety, for now I'll guess it is of the mastermind Collath or Teschner.

Kind Regards,

Raimey
rse