Philip Hensher: Every bubble has to burst eventually

The market in all sorts of things is moving eastwards, but few so fascinatingly as the market in vintage wines. Figures released this week by Sotheby's show that the bulk of its wine sales at auction now takes place in Hong Kong – some $52.6m, compared to just short of $21m in London. Some of the individual figures are astonishing; a single standard-sized bottle of Château Lafite from 1869 sold in October for $232,692. The values of some wines, such as Lafite-Rothschild, have gone up by 1,000 per cent in the last 10 years.

Very surprisingly, too, the typical Chinese buyer is said not to preserve the wine as an investment but, particularly in the case of older vintages, to drink them. More likely, many of them are purchased as ostentatious gifts between billionaires. For whatever reason, the collectors who used to acquire very valuable wines with the intention of ultimately selling them on have been replaced by people who intend to "pull the cork", in the lovely vintner's terminology. That can only fuel the upward rise of prices by stoking rarity. The bubble may carry on inflating for some time yet.

Bubbles are fascinating phenomena to observe, particularly since they never seem like bubbles until they are over. The classical example, since Charles McKay's 1841 book Extraordinary Public Delusions and the Madness of Crowds, is the 1630s Dutch madness for tulips, which in the end saw the price of single bulbs rise to 10 times the annual income of a skilled craftsman.

The South Sea Bubble of 1720 introduced the word to English, but we seem to have grown no wiser since then. There is no shortage of moments when it seemed perfectly sensible to all sorts of people that the value of a commodity or a share would go on rising at a vertiginous rate without any check or deviation – the railway boom of the 1840s is still as good an example as Bernie Madoff, the first dotcom bubble, or the value of property in Tokyo (in the 1980s) or Dublin (in the 2000s). If you want to see what it felt like, then the best place to go is art: the first half of Conrad's Chance, Merdle's downfall in Little Dorrit, or, the whole cycle wonderfully compressed into a single party in the Paris scene of Berg's Lulu.

In a way, the escalating prices of the Chinese wine market seem so strange because – well, because it's only wine, after all. Most of us could tell the difference between a seven quid bottle and a 70 quid one, I suppose. Beyond that, it must be just expertise and an index to its value at auction. But there are still stranger examples of prices which seem to bear no relation at all to any possible intrinsic value – notoriously, the Japanese melons which sometimes sell at auction for tens of thousands of dollars. Fruit in Japanese department stores intended as gifts are often offered for hundreds of dollars. The surface of the cantaloupe is exquisitely even; the taste probably lovely. But how valuable can a melon really be?

The fact with most of these phenomena is that they expand to ludicrous figures when the figures themselves become trackable. When you can demonstrate, as many dealers could, that contemporary art, for instance, has become steadily more and more valuable over the past 15 years, and that it has held its value, then of course that fuels a rise upwards.

One day, one collector will look at another, and say, "Well, I know it's supposed to be very valuable but, frankly, I think it's bloody ugly," and the whole caboodle falls rapidly to the ground. Intrinsically, no bottle of wine is really worth £1,000, let alone hundreds of thousands. But the figures, for the moment, cannot be contradicted. And since it is reported that many of these new millionaires are opening the bottles and drinking them, I don't think it will really make much difference when it is all over. How different is the taste of a wine which is worth a quarter of a million dollars, and one which, you can tell your guests, used to be worth that, before the bubble burst?

A slew of royal weddings could fix the public purse

Wasn't there a royal engagement the other day? Well, now there's another one. Zara Phillips, daughter of the Princess Royal, is marrying a nice-looking rugby player. Their claim on our attention is that if 12 people dropped dead, she would be Queen.

I do hope the souvenir industry is going to exploit this occasion. If the forthcoming wedding of Prince William and Kate Middleton has the value in tourism and memorabilia we were promised, surely a million or two can be wrung out of Zara and her beau, whose name escapes me. Indeed, why not go down the whole line of succession, milking any vaguely appropriate occasion in their lives in objects of porcelain and copperplate?

Entirely at random, I commend Mr Maximilian Lascelles. He is 58th in line to the throne, and 19 years old. If anyone wanted to produce plates commemorating his setting off on a gap year, admission to university, first serious girlfriend, I bet there would be a buyer or two.

If we're going to have a Royal Family at all, the least they can do is perform their duty and prop up our faltering economy in this way.

Cheap flights that put Jordan on the map

Only a generation ago, the antique Nabataean capital of Petra in Jordan was a place of great mystery and antiquity. Probably as recently as the 1980s, a tourist turning up there would have the place to themselves. Now, easyJet has decided to run flights there, and Petra goes the way of Angkor Wat into the hell of mass tourism.

Solitary communion with antiquity has become a rare experience with the ease of travel, and you often have to go to slightly tricky countries to experience it – I commend the Kushite pyramids in Sudan, and Persepolis in Iran and the Roman remains in Libya are still relatively unvisited. Or you could just decide to avoid fashion altogether. For some reason, Byzantine remains are often rather quiet, whether in Syria, or the magical abandoned city of Mystra in the Peloponnese. Strike out for yourself: and, as a rule of thumb, if easyJet flies there, forget it.