Description and Notes:
None of the instruments in this set has a maker's mark except that there is a "Präzision" mark and an identification code VIIP gilded, respectively, on the center and the upper right conner of the case lid. Präzision means "precision" in German, and it appeared on the cases of many German made drawing instruments, such as the ones by Lotter. However the word also had been a trade mark of the company E. O. Richter, as shown on the case lid of this mechanical dotted line pen. Therefore this set is possibly made in Germany by E. O. Richter at around WWII. It should, however, be noted that there is a very similar unsigned set in the Andrew Alpern Collection, p. 92, and the origin of which is described as "a very close copy of the highly successful 'flat system' design of the E. O. Richter company of Chemnitz, Saxony, probably made following the expirationin 1905 of Richter's patent." So this one may also be an imitation of the original Richter's design by an unknown German maker. Yet imitation or not, the instruments are very well made.
The special feature of the large compass and divider in this set is that they have a slider-crank type self-centering mechanism hidden in the joint, such that the orientation of the handle would independent of the opening angle of the arms and remain virticle, as shown in this photo.