Abstract: An apparatus for measuring velocity of chemical reaction by detecting change in light absorbance which stands in proportional relation with time, which comprises arranging plural samples at regular spacings, advancing said samples intermittently at constant intervals, detecting the absorbances with two colorimetric detecting means crossing said samples and measuring the difference between the absorbences thereby determining the reaction velocity of said samples.

Abstract: An apparatus for measuring a chemical reaction velocity of a sample whose light absorbance changes in proportion to time, comprises a differential circuit for converting the absorbance signals at two different times into respective first-order differential signals, or an integrating circuit for integrating the variation of absorbance signal at two times into two integrated signals. A subtractor is provided to obtain the difference of the two differential signals or two integrated signals. The output of the subtractor is compared with a standard level by a comparing means so that abnormality signal is indicated when said difference does not fall into the standard level.