Abstract: A method of correcting first approximation data obtained from a conventional electrozone particle sensing apparatus includes steps for calculating factors for correcting for binary and tertiary coincidences, from the raw data and from physical characteristics of the sensing equipment, to yield an accurate measure of particle distribution within the sample.

Abstract: A suction chamber and at least one sample chamber are located in relatively shiftable operating adjacency. The suction chamber may have a plurality of orifices and the sample chamber a single port for selective registration with the orifices. On the other hand, the suction chamber may have a port or an orifice, and a plurality of sample chambers may have either respective ports or orifices, and the chambers mounted for relative shifting for effecting selective port/orifice registration. A sample depletion detector may be provided in association with the sample chamber. The sample chamber may have a minimum volume residual sample well for maintaining a filled system with the suction chamber to facilitate recurrent sample analyzing function.

Abstract: A method of and means for controlling orientation of particles through a sensing zone in a particle analyzing system, which facilitates particle shape determination, comprises laminar flow orientation of the particles in a stream moving through an elongate straight passage coaxially aligned with an elongate sensing zone longer than the longest particle to be sensed and analyzed. The particles are carried through the sensing zone in an isokinetic laminar flow sheath of fluid.

Abstract: A method of and means for controlling orientation of particles through a sensing zone in a particle analyzing system, which facilitates particle shape determination, comprises laminar flow orientation of the particles in a stream moving through an elongate straight passage coaxially aligned with an elongate sensing zone longer than the longest particle to be sensed and analyzed. The particles are carried through the sensing zone in an isokinetic laminar flow sheath of fluid.

Abstract: Displacement metering with two independently metered fluid flows comprises displacing fluid in laminar filament flow from a first chamber through a second chamber into a third chamber, the chambers being separated by a pair of spaced walls provided with coaxially aligned orifices in communicating series relationship. Flow in filamentary form is effected from the first chamber through the orifices seriatim into the third chamber, and flow is effected from the second chamber through the second orifice into the third chamber in sheathing relation to the filamentary flow. Differential pressure effects the flow from first to third chamber independently but concurrently with positive displacement effecting flow from the second chamber into the third chamber.