For decades the mystery had seemed unsolvable. Then, here in this one-time textile-mill bastion, a team of modern-day detectives tackled the puzzle that has bewildered Westerners since Marco Polo - the Chinese language.
Not surprisingly, it has been the Shanghai-born computer magnate, An Wang, who has helped to crack the case. His researchers, in cooperation with experts in Taiwan, have helped simplify and adapt Chinese to the modern computer keyboard.
Today Chinese-language word processors, such as those developed by the Wang organization and other groups, are being promoted and sold in places like Singapore, Taiwan, and Hong Kong. Creative coding systems, built into a variety of software packages, have enabled operators using a limited keyboard to type thousands of different Chinese characters onto a terminal screen.
Here in the towering modern corporate headquarters of Wang Laboratories Inc., there are concrete indications of how much a standard-size word processor can do. Charles Chuang, a Shanghai-raised product market manager, demonstrates how an operator tapping only 10 numerical keys on a word-processor terminal can ''generate'' up to 15,000 Chinese characters.
The secret, he says, is fairly simple. It's called the three-corner coding system. Here is how it works.
Each Chinese character is considered as a square. Each can be designated by three of its corners, allowing each corner to be represented by a two-digit number. The operator memorizes the two-digit code for each of 99 basic symbols used to make up thousands of characters. To type a character he identifies the symbol used in each of first three corners and then types a total of three two-digit numbeRs (six digits) onto the keyboard. Pressing the ''execute'' key causes the character to appear on the screen.
There are as many methods of tackling the problem as there are computer companies in the field. But all take aim at an obstacle that long blocked development of a Western-style Chinese typewriter: how to reduce the thousands of characters used in the Chinese language into some format triggered by a manageably small keyboard. Not surprisingly, each company says its approach is best.
For example, the New York-based firm of Marian Gatefield Inc. (MGI) has developed a software program in which each key generates on the screen one component stroke, so that by punching several keys an entire character is formed. In an IBM system shortly to be marketed, each key on the main keyboard is labeled with several complete characters. The key selected on a second keyboard determines which character a particular key on the main board will generate. Thus a large number of different possible combinations allows a single keyboard to print out hundreds of different characters.
Just how well these products meet a need is difficult to determine. A Wang spokesman in Lowell says no figures on sales are available. Spokesmen for a number of other companies say their products are too recently developed to show results.
One problem is that the lack of clarity of the character image projected on both screen and printout. ''We ruled out word processing for type setting because the quality is still low,'' explained Kuei-en Deng, editor in chief of the China Times magazine in Taiwan, while on a visit to the United States.
''The quality could be improved, but it would cost a lot more,'' notes Louis Rosenbloom, technical director of the Graphic Arts Research Foundation in Quincy , Mass. (The problem is that the dots used to reproduce characters are still too big for optimal clarity.)
A variety of foreign-made Chinese-language word-processing packages, including Wang's, have been displayed and promoted in the People's Republic of China. But there is no sign China itself has or soon will buy large numbers, sources in the US government and in the computer industry agree. The high cost of full-scale word-processor and information-storage usage, compared with the cheaper cost of old-fashioned methods, are major reasons for Peking's reluctance , these observers suggest.
''It would seem that China has adopted a wait-and-see attitude. They are holding back and experimenting with their own methods,'' says Prof. N. T. Wang, director of China International Business Projects at Columbia University in New York City. ''They already have an inexpensive typewriter system which allows an easily trainable operator to pick up a few hundred characters from an organizing box based on a matrix system.''
''Undoubtedly the fact that Wang is a successful Chinese-American favorably influences the Chinese government, which wants to cultivate such people,'' notes one US government analyst in Washington. But one well-placed independent source following the US computer industry adds that even though the Wang coding system follows a ''Chinese instinct'' in analyzing, organizing, and coding Chinese characters, it has not ''caught on'' with China.
Still, some Wang Chinese-language capabilities are most likely going from Taiwan, where they are manufactured, to the mainland, via Hong Kong, a number of sources agree. China appears to have no objection to such imports coming from Taiwan.
So far China has cautiously used its limited supply of computers mostly for sophisticated research and defense needs. Also, American companies wishing to export computer equipment to China have sometimes faced delays in meeting national-security-related export licensing controls. With no shortage of cheap labor, Peking has also felt free to use more traditional methods for functions that are computerized elsewhere, such as as writing, filing, storage, and inventory controls.