Abstract: A method and apparatus for analyzing the solid matter content of a hydraulically conveyed stream in a conveyor pipeline to be monitored and controlled, comprising, taking of a representative sample of the material in the pipeline across the diameter of the pipeline, separating the solid matter particles in the sample and increasing the liquid proportion in the sample, depositing the separated particles on a filter surface, analyzing the distribution of size and shape of the particles on the filter and adjusting the conveyor accordingly to control a feed pressure in the pipeline and a liquid content of material in the pipeline. The analyzing step is performed by a microscope and a television camera which converts an optical image from the microscope into a signal readable by a computer which, in turn, through a microprocessor, controls a feed pump and liquid input valve.