It gives me great pleasure to acknowledge the help which I have received from various quarters in preparing this translation. Pandit Gangâdhara Sâstrin, C. I. E., of the Benares Sanskrit College, has, with unwearying kindness and patience, supplied me throughout with comments of his own on difficult sections of the text. Pandit Svâmin Râma Misra Sâstrin has rendered me frequent assistance in the earlier portion of my task. And to Mr. A. Venis, the learned Principal of the Benares Sanskrit College, I am indebted for most instructive notes on some passages of a peculiarly technical and abstruse character. Nor can I conclude without expressing my sense of obligation to Colonel G. A. Jacob, whose invaluable 'Concordance to the Principal Upanishads' lightens to an incalculable degree the task of any scholar who is engaged in work bearing on the Vedânta.
