[...] It is only very recently that I have been in a position to give you definite news regarding the fulfilment of the big scheme of which you have heard, and consequently to endeavour to come to terms with you on matters of detail. Accordingly I have to tell you that I am asking each of the distinguished singers who have promised me their co-operation in the Festival Performance of my Ring of the Nibelungs to come to Bayreuth during the coming summer and spend a week or somewhat more there, each according to the requirements of the assigned rôles. The actual dates can be left entirely to the choice of those concerned, only it is very necessary that each should have ample time to go once through his part thoroughly with me. I can then get the singers to study their parts during their winter engagements, on lines suggested by me on this occasion, and get them to rehearse again on agreed dates.
In the summer of 1875 I shall require to get all the singers together for at least a whole month, at whatever time we may decide to be most convenient. Then we will hold rehearsals on the stage itself, with a trial orchestra and the most difficult scenic devices, to test our capacities and discover how far we have got with our study. [...]
Afterwards, in 1876, we shall assemble for three months, June, July and August. The first two months will be spent exclusively in full rehearsals of the four pieces, [...] In August the three complete performances will take place in three successive weeks—Sunday, The Rhinegold; Monday, The Valkyrie; Tuesday, Siegfried; and Wednesday, The Twilight of the Gods. [...]
Having given you a general outline of my plans, I now ask you [...] to grant me your co-operation in bringing them to fulfilment. Now, as ever, I count on you to carry through the exacting rôle of Wotan. In the case of many other singers, I propose to give them several parts alternately. Also I count on our mutual friend Niemann to take the part at any rate of Siegmund, and I do not deny that, as he is undoubtedly the most suitable person, I would like to give him the part of Siegfried as well, if I were not afraid that the two tasks might overtax his strength and that we might in consequence be left in a very difficult position. At present I have no singer in view for Siegfried.
In case it is necessary to touch on the point at once, I may say as regards the pecuniary indemnification of the singers taking part, that there can of course be no question of an honorarium, as is usual with visiting artistes, as the best we can hope for is that the money contributed to assist us will make the performances possible, and it will certainly not cover profits for any of those taking part.
In calculating the sum needed to cover the expenses of those who give their time and talents and so alone make the performances possible, I have gone on the assumption that prima donnas, for example, who will only sing for an honorarium of such and such a sum, are no use to me (and on this account, let me say in passing, I have had to my disappointment to forgo the talented Mme. Mallinger). I have accordingly resolved to allow each of the twenty singers I require travelling and hotel expenses at a maximum rate of five hundred thalers a month, hoping, indeed, that many will be satisfied with less, as there are many of the younger ones who would willingly come on an entirely voluntary basis if I were to invite them. It will be very much more difficult to keep down the expenses of the orchestra (a hundred strong), as a number of musicians must be employed who have no settled engagement and consequently no regular salary. [...]
Source: Letters of Richard Wagner, Vol. 2, selected and ed. Wilhelm Altmann, trans. M. M. Bozman (J. M. Dent & Sons, 1927), No. 667