Description and Notes:
The inscription on the cover of the case are written in Chinese characters, which reads: "Army Artillery Engineering School." Established at 1889, this school was one of the institutes of the Imperial Japanese Army until 1941. The number 39 below the inscription may indicate that this set was belonging to someone of the thirty-ninth term of the school, the graduation year of this term, according to this page, is 1933.
This rare set is unique in that it contains an innovative dotted line pen (or simply dotting or wheel pen) and a dual head ruling pen (or road pen) for drawing parallel curves, the handle of these two pens are made of ivory. It also has a special ruling pen which can be used for drawing both straight lines and arbitrary freehand curves, as the head of which can be adjusted to be either fixed or swirled freely along the curve to be drawn, by tightening or loosening the screw knob at the top of its handle.
It is interesting to note that the top end of the handle of the dotted line pen is actually a compartment which concealed three additional pattern wheels (or rowels). In addition, the front end of the pen can be opened for cleaning or exchanging pattern wheels. A similarly constructed wheel pen can be found on page 16 of Stanley's book A Descriptive Treatise On Mathematical Drawing Instruments, but which does not have the pulley above the wheel to regulate the ink distribution. However, in the same book Stanley does have proposed an innovative idea to regulate the ink by constructing an ink chamber above the rowel, but I have yet to see a working example. It should also be noted that a dotting pen which is exactly of the same design as this one can be found in a set of the Andrew Alpern Collection, pp. 86-87, and that set is identified to be of India origin.
Finally, this set appears to be custom made for the Army Artillery Engineering School, as the Chinese initials of the school are stamped on the dotted line pen and also at the end of the handle of the compass.