... And if you see a grin it's probably just a nervous muscle twitching. At least according to Mr. Auerbach, a professional gag man who once teamed up with an old friend--Herman Wouk--to write for the inimitable Fred Allen. He dubs this a ""true account of the golden days of radio"" but actually it is an inside view of a very specialized breed- the joke suppliers- and in particular the man with whom he served his apprenticeship, a man he calls Lou Jacobs. Jacobs was a gargantuan, cigar-smoking mass of contradictions who managed to service three of the top comics of the day simultaneously while berating his stable and belittling his clients. Example: On the phone... ""Go take yourself a few bows. You deserve them."" Off the phone...""you incompetent paranoid."" The author tells of his adjustment to this ""Augean stable of humor,"" his bouts with the enormous joke file; his promotion to chief laugh clocker; his ""Blue Period""- months spent in a burlesque house writing down the routines of a Minsky comic; his final entrance into the inner circle. His break with Jacobs in search of creative writing (Jacobs was a computer/compiler--reworking old material into new sketches) brought him to Allen and there are some interesting insights into the off-mike man. But this is really a testimonial to men like Jacobs, radio's spark plugs, who turned out routines like short order cooks. Tune in--it's interesting and entertaining.