Isidor Phillip - Exercises for Independence of Fingers - Book 1: Piano Technique

I bought this out of interest as I had picked up Vol 2 in a sale some years back and wanted to complete the set. I have an interest in the history of keyboard etudes and methods and the Phillip's exercises are unusual in that they are entirely constructed on diminished seventh chords in a very wide range of patterns. You play a bar, or a few bars, then shift up a semitone and repeat and so on. No, doubt they will have some effect although the overall sound quickly becomes suggestive of a low-budget horror film. As a tolerable pianist (diploma level) I tried these for a while and they offer reasonable digital exercise and require some brain engagement but I would hesitate to recommend them as a major part of the pianistic diet!