I got the inspiration for this timepiece from my days as a student, and then, for 36 years, as a high-school teacher. One type of test questioning was called “MATCHING”, with two columns, A & B.
The student had to match the correct answer from column B with the question or statement from column A. Thus, the “Matching Test” timepiece.
The time-telling method is really simple, although a study of the diagram below will help greatly to understand it.
On the left side of the dial is a vertical column of numbers representing hours. On the right side is a vertical column representing the mints, in intervals of 5. A stright line (red) connecting a given hour in the left column to a given minute in the right column, represents the time to within 5 minutes. To get the exact time, a vertical line (blue) running the length of the dial will intersect the line connecting the hours and minutes column. The left-right position of the vertical line represents the additional 1-4 minutes that have to be added to get the exact time.
No vertical blue line means that no additional minutes must be added.
Pressing a button on the side of the case chnages the display from time mode to date mode. The date telling method is the same as time-telling, with the hours column changing to months, and the minutes column chnaging to days of the month.
The display can be LCD (less energy use) and constantly displayed, with a press of a button changing the display to date mode; or it can be LED, and displayed ply with the press of a button (once for time, twice for date)
Design by Barry [via]