SPITTING has its uses. It can be beneficial, and not just to clear the throat. "Some old crone let us seek/To spit on us for luck," wrote Theocritus, 2,300 years ago. It can convey a strong social message. "Hal, if I tell thee lie, spit in my face, call me a horse," wrote Shakespeare in Henry IV.
And it can also be used to good effect in diplomatic negotiations, at least in China.
That was the conclusion of some British diplomats after Margaret Thatcher emerged, shaken, from her first meeting with Deng Xiaoping in Beijing's Great Hall of the People in 1982.
As they discussed the future of Hong Kong, Deng spat several times into a spittoon placed near his chair. One British official observed afterwards (according to Robert Cottrell in The End of Hong Kong) that "there has been a lively debate going on far years about whether Deng's habit of spitting into spittoons was done for effect," or whether the communist boss couldn't kick the habit.
Mrs Thatcher had a cold during her visit and undoubtedly used a handkerchief when necessary. But China was not then, nor is it now, a tissue using society. Indeed, many Chinese regard it as unhygienic in the extreme to spit in a piece of soft paper and put it in one's pocket.
The handkerchief, in fact, is a relatively recent sanitary device in modern societies. Cultivated Europeans travelling to the US in the 19th century recorded their disgust at the American habit of spitting noisily into metal receptacles.
The expectoration of the colonists arose, or one might say, emerged, as a result of self indulgence, since tobacco chewing was then a national habit.
It is not so long ago either that pubs in Ireland also had spittoons in the corner, which were probably more hygienic than tissues, as the contents were absorbed by sawdust and safely disposed of.
But "No Spitting" signs were placed in blocks of flats and on streets in Dublin in the 1950s when health authorities discovered that after spit dried out, the TB bacillus survived and became a dust particle.
In China today similar concerns and growing health awareness cause authorities to frown on the social habits of centuries, though it is still not uncommon, and slightly shocking to visitors to see a well groomed woman hawking noisily on a city pavement.
There have been anti spitting campaigns in Beijing in the past, and police have been authorised to fine spitters on the spot. Enthusiastic hygiene cadres have even been known to produce a microscope and require culprits to go down on their hands and knees to see just what they have deposited on the pavement.
However, people living here spit mainly because they have to, and indeed many foreigners find that they develop such severe nasal problems from pollution and dust that they, too, develop the Chinese syndrome and attempted to hawk along with the rest.
This is a coal burning society. Travel along any Beijing street and count the number of tricycle carts piled high with dusty coal briquettes, which will be burned in countless houses and end up as sulphur dioxide in the atmosphere.
Beijing also has a high rate of carbon monoxide emissions from vehicles which are poorly tuned and spend long periods caught in traffic jams. It has hundreds of oil and coal burning factories and chemical plants.
Add to this the ozone in a dry climate with nine months of unremitting sunshine a year and the result is a potent, spit inducing, soup like atmosphere.
"It is very likely that the particular mixture of pollutants combined with high ultraviolet light due to the lack of cloud cover are the most favourable circumstances to produce high ozone levels here," explained Dr Seamus Ryan, a Kildare man who is chief medical officer of Beijing's International Medical Centre. Dr Ryan gave a recent lecture on air pollution and its effects on health.
"And the unique effect of ozone is to increase mucus products from the nose and lungs due to its irritating effect," he said.
So Deng Xiaoping had to clear his throat regularly, living in Beijing as he did, and chain smoking to boot. But with his passing last week, so, too, has died the notion of a spittoon as a diplomatic device.
The new breed of Chinese leaders, the so called third generation of technocrats, do not wear Mao suits like Deng, nor do they spit. When Premier Li Peng gave his state of the nation address on Saturday he wore a business suit and polka dot tie. And I bet he had a handkerchief in his pocket.