Time interval measuring instrument

Time interval measuring instrument, comprising:

• elongate marking means defining a row of time intervals limited by marking lines, with a row of figures associated with the time intervals, respectively, and having increasing numerical values, with a lowest numerical value being at a bottom and a highest numerical value being at a top;
• elongate receiving means extending parallel to the marking means for receiving indicator parts which form a row in the receiving means, with a desired quantity of the indicator parts being added or removed;
• and
• a base for supporting the marking and receiving means,
• wherein the marking means comprises flat marking strip means provided with marking lines and figures and arranged sidewise of and adjacent to the receiving means as a functionally separate part thereof,
• wherein the receiving means comprises a transparent guide having a bottom on which the indicator parts are piled up and which lies on the base, and an opening provided at a top of the guide for putting the indicator parts in,
• wherein the indicator parts are formed as standard parts which are put into the guide through the top opening and slide freely along the guide in a direction toward the guide bottom and which form a stock an upper end of which is associated with the marking strip means.