Vicentino's description of his first tuning, has some puzzling statements if it is understood as 31 equal. He says that the major third from C to E is made closer to pure if it uses the slightly lower pitched C on the front keyboard with the slightly higher pitched E from the back keyboard. This is puzzling because in pure 31 equal all the major thirds should have been almost exactly pure already. Karol Berger's analysis of this suggests that he may actually have used a somewhat unequal tuning for his extended meantone system, varying perhaps from 0.2 comma smaller than pure to 1/3 comma larger than pure.