FIG. 1 is a top plan view of a laboratory jack of the invention;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a bottom plan view thereof;
FIG. 5 is one side elevational view thereof, the other side being a mirror image;
FIG. 6 is a top plan view of the laboratory jack of the invention in the expanded position;
FIG. 7 is a front elevational view thereof;
FIG. 8 is a rear elevational view thereof;
FIG. 9 is a bottom plan view thereof; and,
FIG. 10 is one side elevational view, the other being a mirror image.
The broken line showing some elements in the figures is for illustrative purposes only and forms no part of the claimed design.