Doctors tired of reciting the same old line might try this variation: "Take two Haydn symphonies and call me in the morning." More bracing than a cold shower, at least as substantial as chicken soup, Papa Haydn's symphonic tonics are good for what ails you, and there's no risk of stomach upset. These are among his best. You can tell from their numbering that he already had some experience with the form. His first 50 or so efforts are generally regarded as mere warm-ups for the next 40, when he began to show flashes of brilliance in rendering emotion and structuring his ideas. When he hit No. 92 in 1789 (he was 57), he was in full flower. The next dozen did for the symphony what Babe Ruth did for the home run. They were commissioned by a London impresario, Johann Salomon, and Haydn's trips to London to conduct the premieres were heralded events. If there had been a Good Morning America in the 1790s, it would have sent its David Hartmann to do a remote. Then or now, Haydn couldn't find a more polished and vibrant orchestra to play his mature works than the London Philharmonic, or a more able, sensitive conductor than Solti.