Abstract: A colorimeter in which a light source, a collimating lens and a band pass filter are supported by a housing that is movable with respect to a stationary beam dividing assembly in a direction at least substantially transverse to the optical axis of the light from the source. The assembly separates the incoming collimated and filtered light into a sample beam and a reference beam which are directed back toward the housing in directions parallel to the optical axis. The movement of the housing toward or away from the sample produces an increase or decrease in the intensity of the light illuminating the sample and a corresponding decrease or increase in the intensity of the light at the reference detector. The arrangement is such that the apparatus may be readily adjusted to obtain accurate colorimeter readings even for samples having abnormally high or low density characteristics.

Abstract: A liquid sampling apparatus includes a sample carrier supporting a plurality of sample containers arrayed in a generally spiral pattern for successive passage through a sampling station at which a sampling tube removes a small quantity of liquid from each container. A receptacle for containing a wash liquid is located adjacent the sampling station, and the wash liquid is supplied to the sampling tube between the taking of successive samples in order to cleanse the sampling tube.

Abstract: A colorimeter in which a beam dividing assembly is supported on a movable carriage intermediate the sample and reference detectors. The assembly separates the incoming collimated light into a sample beam and a reference beam. The movement of the carriage toward or away from the sample produces a decrease or increase in the intensity of the light illuminating the sample and a corresponding increase or decrease in the intensity of the light at the reference detector. The arrangement is such that the apparatus may be readily adjusted to obtain accurate colorimeter readings even for samples having abnormally high or low density characteristics.