of the great masters because of the abundance of details one comes upon which point the way to the later development. Here lies completed what was there foreshadowed. Things that were at first cultivated are later rejected. The obstacles to such research are of two kinds: at one time the necessary sources of material for comparison are difficult of access, at another they are so plentiful as to make impossible any even approximately complete treatment. Sometimes both difficulties combine. That is why even the standard biographies of the heroes of musical history have mostly had to confine themselves to the mere sketching of composers' relations with their forerunners, and have been able to trace stylistic connections, particularly, only with the immediate predecessors of their subjects. The easiest possibilities of influence to determine are those of time and place, especially if the musician in question came in contact with various style-currents through travel in his youth-for it is in connection with the youth of composers that such investigations encounter the most plentiful material. It is almost never possible, on the other hand, to establish what works came to the ears of the visitor-whether only those of local and living musicians, or those of earlier and foreign composers as well. A limitation of the works to be examined as far as time is concerned may, it is true, be arrived at, although such a limitation must always be somewhat arbitrary, since the evolution of taste and style makes it likely that the riches of earlier times were probably neglected. But a limitation as to place is much more difficult, and may usually be attempted only-and then with precaution-when special conditions confined the practice of certain branches of music to the works of specific periods and places. Such conditions prevailed in the I7th century in the Sepolcro at the Imperial Court of Vienna and in its vicinity, where local considerations, con-