The ornamental design of a measuringinstrument, as shown and described.
FIGS. 1 and 2 are lower perspective views of the measuring instrument of my new design;
FIG. 3 is a top plan view of the measuring instrument of my new design;
FIG. 4 is a right side view of the measuring instrument of my new design;
FIG. 5 is a bottom plan view of the measuring instrument of my new design;
FIG. 6 is a front end view of the measuring instrument of my new design; and,
FIG. 7 is a rear end view of the measuring instrument of my new design.
The broken line portions of the drawings are included for the purpose of context and illustrate unclaimed structure and form no part of the claimed design.