Horseplayers of other eras couldn't have imagined the bet I made here the other day. I parlayed a horse in the second race at Bay Meadows to a horse in the ninth race at Aqueduct -- tracks 3,000 miles apart -- and watched them run simultaneously.

Post time for the two events happened to be a few seconds apart, with both of the races being telecast live on giant screens at the Caesars Palace Race Book. My eyes darted from screen to screen. I let out a cheer as my Bay Meadows horse surged to the front, but a moment later I saw that my Aqueduct horse was blowing a four-length lead. Even so, I didn't mind too much that I blew the bet; it was worth the price to have so much action.

The introduction of simulcasting here has enlivened the horse-betting business in this town and possibly foreshadowed a trend for the whole racing industry.

Until recently, the race books here bore a great resemblance to cliched bookie joints from Hollywood movies. Clerks recorded wagers in longhand. The calls of races over the P.A. system came 10 or 20 minutes after the event, and were re-creations emanating from an office in downtown Las Vegas. An employe would then use a Magic Marker to post results and payoffs on a big board.

The technology for simulcasting had existed but had gone unused here, partly because of resistance from the state's Gaming Control Board, partly because of resistance from tracks. "When this first started," said Ed Clarke, the manager of the Caesars Palace Race Book, "the tracks thought that we might take business away from them. But nothing of the sort has happened."

When the opposition faded, independent operators -- known as "disseminators" -- started making contracts with racetracks and then selling their television signals to the race books here. And suddenly Las Vegas had a wonderful new game.

The old race books catered to hard-core horseplayers and had little need for amenities. But live telecasts of races would appeal to vacationers and recreational gamblers, who would expect typical casino comforts while they spent their dollars. Caesars Palace obliged them by constructing the most snazzy, high-tech, action-filled bookie joint any horseplayer could want.

Patrons sit in rows of desks, each with its own reading light, so they can study the fine print in the eastern, midwestern and western editions of the Daily Racing Form. In the front of the room, are four big electronic boards that show entries and results from the four principal tracks operating that day. Next to them are five giant screens that show the races, as well as the changing odds from various tracks.

Saturday, Caesars Palace was telecasting the races from Aqueduct, Gulfstream, Bay Meadows and Santa Anita. For more than an hour in early afternoon, local time, all four of them were operating simultaneously. In case anybody still was hungry for action, Caesars and other race books around town offered nighttime simulcasting on quarter-horse races in California, harness racing in New York and dog racing in Arizona.

This may be the first time in the history of Las Vegas that any casino official ever has fretted that there is too much action here. "We're open from nine in the morning to midnight," Clarke said. "Later on down the line we may refine this to a point where we're only showing two tracks at the same time. How much racing can you give somebody?"

As much as possible, I would say. The quantity of action available here now is a horseplayer's idea of heaven.