The most well-known principles of artifical kidneys (those which are already in use as well as those which are being developed) and the principles of the partial kidneys are subdivided into a sequence of ordinal numbers. 2. Here these methods are critized partly more briefly, partly more detailed. 3. The author deals with some details of the A-coal-adsorption, in which case the uraemic detoxication is particularly taken into consideration. 4. Then the essential advantages of the use of adsorbents in the uraemic detoxication and in the removal of toxines in general as well as their significance for the construction of modern artificial kidneys are compiled.