Changes in production and in physico-chemical properties of bronchial mucus is a common denominator of many pulmonary diseases. A rheometer with innovative features aimed at bronchial mucus routine investigation in clinical practice at the bedside of the patient has been designed. Searle-type configuration with a coaxial cylinder sensor system and the Mooney-Ewart geometry has been adopted. Another new feature is that bob and cup are disposable. Dynamic viscoelasticity is calculated through a microprocessor with specific software and by means of a magnetic torque--motor electronically driven by the microprocessor. The self-zeroing procedure and the autorange greatly simplify the measuring-cycle which is driven by only one switch. Data (eta and G') are automatically printed on paper. The whole measuring-cycle at the bedside of the patient takes 3-5 min, so that in 1h about 12 samples can be investigated.