Commerce, however, has begun to intrude on this simple pleasure. At least one Chinese restaurant in Manhattan is sending out delivery orders in cartons adorned not with the traditional "Thank You, Enjoy," but with something a bit more jarring: an advertisement for Cingular Wireless, a purveyor of cellular phone service.

From a distance, the boxes are indistinguishable from millions of similar Chinese food containers, but closer inspection reveals that one side reads "I H New York." Another bears the message "Cingular Wireless: Swing by one of our retail locations below."

Devotees of Chinese takeout consulted for this article generally agreed that they had not previously seen corporate advertising on any of those ubiquitous white delivery cartons. So a call was placed to The Chinese Restaurant News, a trade publication based in Chinatown.

"Oh wow," said Grace Leung, a reporter. "I never heard of that before."

Perhaps it was inevitable. Advertising has already made it onto cardboard coffee cups and yellow cabs. The bare white sides of the takeout carton must have seemed like tiny billboards for a company with something to sell.

The cartons bearing Cingular's ads were traced to Grand Sichuan International Midtown, a restaurant on Ninth Avenue and 50th Street, where the menu includes poetic-sounding dishes like Growing Grass in Spring Must Be Like Green and Green Parrot With a Red Mouth.

"In all the ways that count," a New York Times review of the restaurant published in September 2000 reads, "Grand Sichuan stands out."

Sunny Yan is a waiter there. He said the boxes were given to Grand Sichuan two weeks ago by a man who asked the restaurant to try them.

"It was free, no money," Mr. Yan recalled as he kept a watchful eye on his customers. "They just want to promote their products."

Apparently, the man left neither a business card nor a telephone number, and Mr. Yan said it was unclear whether he was working for Cingular or, perhaps, for a Chinese food carton concern.

According to Ms. Leung, a handful of carton companies supply the Chinese restaurants of New York.

Mr. Yan did manage to recall that the man was young, wore glasses and was smartly dressed, and that the two boxes of cartons he left behind caused quite a stir.

"It's the first time I had ever seen a box like this before," Mr. Yan said. "I never had that kind of experience. I was so surprised."

A spokeswoman for Cingular did not return several messages left at her office yesterday, and a curious reporter was left to speculate on the connection between Chinese takeout and cellular phones.

Would customers given to placing delivery orders buy cellphones to call a restaurant in advance — perhaps from the car, the bus or the street?

"It's a good idea," Mr. Yan said with a smile and a nod.

Or would customers be put off by advertisements on the vessel bearing their pork fried rice?

"I think it's cool," said a man named Brad, who was dining alone in the restaurant and swapped his opinion for partial anonymity. "Why should it bother me if someone sticks an ad on the box?"