Abstract: An inspection block is disclosed for use in inspection of biological matter in a container unit which has a chamber with transparent walls, the inspection block having a transverse docking passage for receiving and positioning a container unit, an observation chamber extending transversely relative to the docking passage and in communication therewith such that the biological matter located inside the container unit may be microscopically inspected through the chamber walls, transparent liquid for immersing at least part of the container unit so as to define a chamber wall/liquid optical interface for microscopic inspection therethrough. The inspection block may be made of steel, aluminum or plastic. In the latter case, the plastic inspection block may have closed cavities for containing insulating blocks and/or one or more downwardly opening air pockets retaining heat given off by a warmed work bench and/or warmed microscope stage on which the inspection block is supported during inspection.