"Mr. Handel's head is more full of maggots than ever," wrote Charles Jennes to his cousin, Lord Guernsey, on Sept. 19, 1938. Jennens was George Frederick Handel's principal librettist, the author of the texts for such oratorios as "Saul," "Belshazzar" and "Messiah," among others.

"I found yesterday in his room," Jennens went on, "a very queer instrument which he calls carillon (Anglice, a bell) and says some call it a Tubalcain, I suppose because it is both in the make and tone like a set of Hammers striking upon anvils. "Tis played upon with keys like a Harpsichord and with this Cyclopean instrument he designs to amke poor Saul stark mad.

"His second maggot is an organ of 500 pounds price which (because he is overstocked with money) he has bespoke of one Moss of Barnet. This organ, he says, is so constructed that as he sits at it he had a better command of his performers that he used to have, and he is highly delighted to think with what exactness his Oratorio will be performed by the help of this organ; so that for the future instead of beating time at his oratorios, he is to sit at the organ all the time with his back to the Audience."

"His third maggot," Jennens wrote, "is a Hallelujah which he has trump'd up at the end of his oratorio since I went into the Country, because he thought the conclusion of the oratorio not Grand enough; tho' if that were the ccase 'twas his own fault, for the words would have bore as Grand Musick as he could have set 'em to: but this Hallelujah, Grand as it is, comes in very nonsensically, having no manner of relation to what goes before. And this is the more extraordinary, because he refused to set a Hallelujah at the end of the first Chorus in the Oratorio, where I had placed one and where it as to be introduced with the utmost propriety, upon a pretense that it would make the entertainment too long, I could tell you more of his maggots: but it grows late and I must defer the rest till I write next, by which time, i doubt not, more new ones will breed in his Brain."

All these "maggots" will be on display in the Kennedy Center on Monday, Jan. 17, when "Saul" by Handel, with libretto by Jennens, opens the Center's Handel Festival. "Saul" will be followed in February by the opera "Rinaldo" and in April by "Solomon."

Stephen Simon, the music director of the festival, reminds us that Handel had written 44 operas, and, although he did not say so, they are unsurpassed in the entire century and a half of baroque opera, standing easily with the greatest of Monteverdi and Rameua.

Handel turned to the oratorio when it was no longer economically possible for him to produce opera in London. Various factors combined to switch him over to the form for which the world at large best remembers him today: "Opera seria" had become a prisoner of the worst kinds of artificial conventions, the English had a habit, at regular intervals, of forbidding all forms of theatrical performances during Lent; John Gay's "Beggar's Opera" appeared on the scene, with its English language and its cast of characters drawn from pickpockets, whores and cutthroats, who suddenly seemed far more attractive to the English opera audiences than the shepherds, nymphs and goddesses with which opera had, up to that time, been peopled; and, finally, the English love of religous spectacles, which Handel's oratorios quickly became.

Today Handel's operas are enjoying a modest revial: "Julius Caesar," one of the greatest, became a hit when the New York City Opera presented it with Beverly Sills and Norman Treigle superbly cast as Caesar and Cleopatra. And Kennedy Center fans will remember the glorious production of "Ariodante," given in the Opera House during the Center's opening week. "Rinaldo," which Simon will conduct on Feb. 28, is one of Handel's earliest triumphs and, like most of his great vocal works, loaded with melody.

In "Saul," Handel and Jennens have given us a brilliant psychological drama, centering on Saul's gradual disintegration because of his uncontrollable jealousy of David. Jennens takes the Book of Samuel for his starting point, but creates, like an early Boito, a human monster whose irrational jealousy drives him to murderous hatred.

jennens has a wonderfully Georgian phrase for Goliath: "Along the monster atheist strode, with more than living pride." Bud David "with ease the boaster slew." The only problem after that was Saul's mounting jealousy of the young man. And when the women of Saul's court sind "Saul, who hast thy thousand slain. David his ten thousands slew," Saul blew his stack. "Have I sunk so low, to have this upstart boy prefer'd before me? What can they give him more except the kingdom?"

And so, after trying divers ways of having David killed, Saul goes on his famous visit to the Witch of Endor, even though he himself had forbidden anyone to consult her. When she, at his bidding, calls up the ghost of Samuel, Saul has had it. He hears that he must die the next day. And David's life is safe. For all this Handel calls up some of his greatest music: In as large an orchestra as he ever used, he includes trumpets and trombones, large military drums, and, of course, the carillon.These days, most conductors make do with some combination of glockenspiels, celeste and organ bells, since Handel's kind of carillon is a little hard to come by.