Vial autosampler

Apparatus for spectrophotometric analysis of a material by reflectance measurements resulting from a beam of electromagnetic radiation applied to the material which comprises a station at which a container housing the material is to be located for said measurements and means for carrying an array of said containers and feeding each of said containers successively to locate said container at said station for said measurement and removing said container from said station following said measurement, said means for carrying, feeding and removing said array of said containers comprising an endless conveyor, where intermittent displacement of said conveyor feeds each of said containers successively to said station, retains said container stationary at said station for said measurement and displaces to remove said container from said station following said measurement, said station comprising a seating to which said container is fed to be accommodated and retained in a predetermined position for said measurement, said seating being carried by a plate having an aperture through which said beam is applied to said material and said measurements are detected, said plate being opaque and substantially non-reflective to said electromagnetic radiation, said seating coinciding with said aperture, and a guide surface associated with said seating and with which said container on said conveyor may abut, said guide surface serving to provide a lead-in for said container as said container is fed to said seating to assist in location of said container at said seating.