The effects of medicaments, used in the treatment of arthritic diseases, on the surface tension of the synovial fluid have been measured. The synovial fluid was obtained from the carpal joints of freshly slaughtered 'calves and from knee joints of arthritic patients. Values obtained for the surface tension (~) of the pure liquids were 47. 6 mN/m and 45. 8 mN/m respectively. The surfGBPce tensions of the additives and their effect,as a function of concentration, on the surface tension of synovial fluid are shown in figure 2. From this diagram it can be seen that bone and cartilage extract(K u....