Additions to an artificial circulation model are descr. These include the visual demonstration of the hydrodynamics of varicosities, arteriovenous fistulae, aortic elasticity alterations, aortic aneurysms, sphygmomanometry, oscillometry, coarctation, and the unique nature of the coronary circulation. The apparatus is made of common materials and is easy to construct. With the machine, the student can personally examine some of the hydraulic characteristics of the circulation and carry out expts. on the effect of various factors on pressure pulses and flow.