The machine is configured to perform an automated rapid plasma reagent (RPR) agglutination test or other agglutination test. The machine includes a sample rack with multiple sample locations thereon and a reagent rack for storing of reagent. A shaker assembly supports at least one microtiter plate or other well supporting structure thereon with a plurality of wells in the plate. An automated pipette accesses samples and reagent and deposits them within wells of the microtiter plate. The shaker assembly shakes multiple samples within the wells of the microtiter plate. Finally, a camera photographs the wells of the plate, preferably from above with a light source below and the plate at least partially transparent. The image is then analyzed in an automated fashion to determine whether a ring of contrast material has remained smooth indicative of a non-reactive sample or has agglutinated/clumped together indicative of a reactive sample.