Caution: reading this column may be hazardous to your mental health. For here comes the puzzle that's sweeping America.

It's called the "Equation Analysis Test." It was devised by Will Shortz, senior editor of Games magazine. It is absolutely, positively guaranteed to drive you out of your mind, or your money back.

The game consists of familiar sayings or truths, presented in code. The object of the game is to decipher the code.

For example, if a clue is presented as "26=L. of the A.", it's up to you to figure out that that means "26 equals Letters of the Alphabet."

But they get much tougher than that. For example, would you be able to guess "3=M. in a T. (R.D.D.)"?

Give up? It's "3 equals men in a tub (rubba dub dub)".

Back in March, Joe Browne, a columnizing cousin of mine who writes for the Pittsburgh Post-Gazette, published the collection that follows. He reports that although the cries of anguish have slackened a bit, letters are still coming in, asking for reprints of the answers or a new set of questions.

"I've never seen anything like how many people tried the puzzle, and how few could get all the questions right," Joe says.

How right he is. I hacked away at the list for several days, and came up with only two-thirds. And this from a "wordie" who can usually lay the Sunday New York Times crossword puzzle to rest in an hour.

Feeling challenged? On your marks, get set, go. First reader to mail in a perfect ballot wins a free lunch, as well as several paragraphs in this column to explain to the world how he/she did it.

7=W. of the A. W.

1001=A.N.

12=S. of the Z.

54=C. in a D. with the J.

9=P. in the S.S.

88=P.K.

13=S. on the A.F.

32=D.F. at which W.F.

18=H. on a G.C.

90=D. in a R.A.

200=D. for a P.G. in M.

8=S. on a S.S.

3=B.M. (S.H.T.R.).

4=Q. in a G.

1=W. on a U.

5=D. in a Z.C.

57=H.V.

11=P. on a F.T.

1000=W. that a P. is W.

29=D. in F. in a L.Y.

64=S. on a C.

40=D. and N. of the G.F.

13=B.D.

3=S. to the W.

Dessert:

John Bessor of Alexandria has submitted a list of 609 words compiled from among the letters of the word "ESTABLISHMENT."

John defies you to find more. If you do, same offer as above: one lunch, with Levey picking up the check, and one very public chance to explain why you're so brilliant.

Here are the rules:

* Words must be at least three letters long.

* No letter may be used more than once. However, since "ESTABLISHMENT" contains two S's, two E's and two T's, each of those letters may be used twice. But they may not be used three times or more in a single word.

* Words must appear in a recognized dictionary of the English language. However, anything marked "obsolete" is not allowed.

* Foreign words are acceptable if they have wormed their way into general usage (for example, "blase"). In the event of disputes, my word and Webster's are final.

* You may not claim credit for a new word simply by adding an "s" to one you've already listed. However, if a plural is obtained by changing one letter, that's OK. For example, "thesis" and "theses" are both acceptable. So are "basis" and "bases." But "bases" as a plural of "base" is not.

* No proper nouns allowed.

Final instruction: check to be sure your hair is still atop your head. You'll soon be tearing it out.

Answers to both puzzles will appear in one week.

Mail all entries--and war stories about how you sat up in bed at 3 a.m. and declared to the wallpaper, "I've got it!"--to:

Bob Levey, The Washington Post, Washington, D.C., 20071.

Happy suffering!