IT'S the way you have to make a detour before entering the premises which distinguishes fung shui consultant Wong Man-chui's office from a college geography teaching room. ''For offices, the location of the entrance is most essential,'' said Wong as he pointed at the oblique entrance in his 400 sq ft office in Causeway Bay. ''The door is where customers and money come in, so its position is very important. If the door was built in the wrong place, this can only be solved by creating a symbolic doorway which will bring in luck and money. So I had to rearrange my tables and chairs to form this second entrance.'' And judging by the number of his students and his long list of clientele, which includes Hong Kong's most bankable names, it was definitely worth the shuffle and rearrangement. Wong, alias Koon Lung (which means watching the dragon or mountain range in Cantonese), is no ordinary geomancer. A look around his office, where maps of Hong Kong and pictures of compasses are like wallpaper, the 43-year-old appears to be more of a scientist than a fung shui man. ''I am probably among the few in Hong Kong who studies the history of and makes compasses. Since 1986, I have made over 3,000 of them. The new ones I'm making now belong to the ninth generations [of my work],'' Wong said. ''Over the years, I have wanted to improve the accuracy of my compasses. It is the usage and accuracy of fung shui compasses that interests me most. Nowadays, there are a lot of phonies who just use the compass to impress. ''I have visited China in the past to look at ancient compasses. However, there are not many of those around today because many were burnt during the Cultural Revolution.'' Wong sells some of his compasses to collectors, though these instruments can be put to practical use. ''The compass is indispensable in the fung shui science as it is the only instrument which determines the position of a house, or a grave,'' Wong said. ''Fung shui is all about the harmony between people and the environment which they live in. While it is easy for anyone to tell whether a flat looks or feels comfortable, you'd need a compass to measure the position of the building and to find the money and healthy 'spots'. '' According to Wong, a good compass has to be accurate - the magnetic north has to be correct, the lines crossing the compass have to be straight, and the circular copper plate surface has to be divided into 64 segments and 30 inner rings. ''Naturally, the more accurate the measurement, the more accurate can the future be foretold,'' he said. ''All my compasses are made out of thick to mok, a special kind of wood that chases the evil spirits away.'' Wong needs bigger compasses because of the jungle of steel which distorts the magnetic field. Having found the position of the house and the auspicious spots for beds and fish tanks, you need to look to your own birth sign. ''After all, not only is it important that you like the house, the house also has to like you. But in fung shui, we can always make remedies to avoid any clashes between the people and their environment,'' he said. But he warned that there were a lot of swindlers out there who claimed to be fung shui men but knew nothing about the arts. ''The compass is only used after the fung shui man has taken a good thorough look around the flat. Those who use it immediately upon entry are likely to be phonies.''