In those days it was the custom to attend the rehearsals of a piece which happened to be arousing an unusual amount of interest, and the demand for admission to those of _Iphigénie_ was so great that La Vrillière wrote to the directors of the Opera, ordering them to take special precautions to avoid any disturbance and to allow no one to enter without a ticket signed by themselves. The desire to be present is not difficult to understand, since to see Gluck at a rehearsal must have been a sight not easily forgotten. Throwing off his coat and replacing his wig by an old cotton night-cap, he would dart about the stage, imploring Mlle. Arnould to follow his music, M. Larrivée not to sing through his nose, M. Legros to endeavour to express something at least of the dignity and nobility which one was accustomed to associate with the great champion of the Greeks, and the chorus to endeavour to look and move a little less like automata. “Look you, Mademoiselle!” he would cry, purple with passion, when Sophie or some other actress proved more than usually contumacious, “I am here to make you perform _Iphigénie_. If you are willing to sing, nothing can be better. If you are not willing to do so, do not trouble. I will go and see Madame la Dauphine and tell her what you say. If it is impossible for me to get my opera produced, I shall order my travelling-carriage and take the road to Vienna.” This indeed was no idle threat, and had it not been for the support accorded him by Marie Antoinette, there can be very little doubt that he would have shaken the dust of Paris off his feet. But, with the Dauphiness behind him, the malcontents, grumble as they might, had no option but to obey this terrible man, whom they devoutly wished at the bottom of the Seine. The first performance was fixed for April 13, 1774, but almost at the last moment Legros announced that he was too ill to appear. Gluck immediately demanded the postponement of the opera. The management pointed out that the Royal Family were to be present, and that all arrangements had been made for their reception, and begged him to allow another singer to take the place of the absent tenor. The composer rejoined that, rather than see his work mutilated by an inferior rendering of so important a part, he would throw it into the fire; and the directors were compelled to give way.