The first Defense Department use of the program was in the Air Force Technical Applications Command (AFTAC), which found it entirely satisfactory for its mission of monitoring nuclear events throughout the world in accordance with arms control treaties. The Navy Research Laboratory also redrafted it for its own purposes. Though inadequate for seismic predictions, it worked very well indeed in analyzing sonar signals. The program was known in the navy as the signal algorithmic processing system (SAPS).

"SAPS SIGNAL INPUT," Jones typed into the video display terminal (VDT).

"READY," the BC-10 responded at once.

"RUN."

"WORKING."

For all the fantastic speed of the BC-10, the six hundred thousand steps of the program, punctuated by numerous GOTO loops, took time to run as the machine eliminated natural sounds with its random profile criteria and then locked into the anomalous signal. It took twenty seconds, an eternity in computer time. The answer came up on the VDT. Jones pressed a key to generate a copy on the adjacent matrix printer.

"Hmph." Jones tore off the page. "'ANOMALOUS SIGNAL EVALUATED AS MAGMA DISPLACEMENT.' That's SAPS' way of saying take two aspirin and call me at end of the watch."

Thompson chuckled. For all the ballyhoo that had accompanied the new system, it was not all that popular in the fleet. "Remember what the papers said when we were in England ? Something about seismic activity around Iceland , like when that island poked up back in the sixties."

Jones lit another cigarette. He knew the student who had originally drafted this abortion they called SAPS. One problem was that it had a nasty habit of analyzing the wrong signal—and you couldn't tell it was wrong from the results. Besides, since it had been originally designed to look for seismic events, Jones suspected it of a tendency to interpret anomalies as seismic events. He didn't like the built-in bias, which he felt the research laboratory had not entirely removed. It was one thing to use computers as a tool, quite another to let them do your thinking for you. Besides, they were always discovering new sea sounds that nobody had ever heard before, much less classified.

"Sir, the frequency is all wrong for one thing—nowhere near low enough. How 'bout I try an' track in on this signal with the R-15?" Jones referred to the towed array of passive sensors the Dallas was trailing behind her at low speed.

Commander Mancuso came in just then, the usual mug of coffee in his hand. If there was one frightening thing about the captain, Thompson thought, it was his talent for showing up when something was going on. Did he have the whole boat wired?

"Just wandering by," he said casually. "What's happening this fine day?" The captain leaned against the bulkhead. He was a small man, only five eight, who had fought a battle against his waistline all his life and was now losing because of the good food and lack of exercise on a submarine. His dark eyes were surrounded by laugh lines that were always deeper when he was playing a trick on another ship.