A photoelectric cell collects the light which passes through the cuvette. Clotting starts when activator with immobilized TF is immersed into the cuvette. Before the rectangular cuvette was created, ordinary test tubes were used. Severinghaus improved the design by adding a stirred cuvette in a thermostat. The dye cell, or cuvette, is usually very small. Paper towel or similar may scratch the cuvette. It borders the departments of Cuvette and Sangha, and Gabon. It is the capital of Cuvette Department and an autonomous commune. The issue of parks versus people is salient in the Cuvette Centrale the bonobos' range.