Abstract: The invention contemplates a cuvette or cell construction which is especially adapted to enable photometer or the like measurement of sample fluid admitted to the measurement chamber of the cell. The construction is applicable to fluid analysis under either the condition of a continuous-flow of specimen fluid, or under the condition that a single small sample has been vacuum-induced into the measurement chamber. The construction is inherently simple, is inherently self-clearing of air or gas bubbles in liquid samples, and provides inherently efficient cleansing of the measurement chamber when examined sample is withdrawn.

Abstract: The invention contemplates instrumentation to enable performance of a plurality of automatic photometric analyses upon liquid samples, as in different analyses of such body fluids as blood, urine, etc. Prior to photometric evaluation, the liquid samples are automatically subjected to controlled doses of one or more reagents, and dwell times, as appropriate to the analysis to be performed at any given time. The particular automatic performance of a given analysis is supplied from an insertably replaceable holder which contains the reagents, dosage devices, and program-control coding unique to the particular analysis. Upon inserted replacement of the holder with another selected holder which is suitably encoded and equipped with reagents, the same instrument will serve for the handling of liquid samples unique to a different biological analysis.

Abstract: The invention contemplates continuous monitoring of a sample solution for cloud disturbances while conducting absorption-photometry measurements on the solution. The absorption-photometry measurements are a function of light directly transmitted through the sample solution, and the cloud disturbances are observed to the extent that the same light is or may be dispersed by cloud particles, in one lateral direction from the direct-transmission axis.