There are other ways in which the Net bothers small children less than it does adults. Children are natural surfers, with their apparently insatiable appetite for the next piece of information. The triviality of the information does not matter.
The young are also far more patient than their elders. Where we twitch at the slowness of computer speaking to computer around the world, Adam treats the wait as personal down-time, drumming his heels reflectively.
CD-Rom discs are faster, he agrees, but the few he has are not new. Novelty value is important to him. Still, it is clear that if the Net is to keep up its growth, faster connections in the home will be essential.
It is easy for a child to learn how to click on the right icons to dial up and use a browser - Netscape in our case. Most probably have the manual dexterity by the time they are three. The mechanics become even easier for a child who can read confidently.
Far more difficult is the question of what they will get out of it, apart from familiarity with the brave new world of communications technology. One obvious answer is the sheer pleasure of browsing, the sense of potential discoveries being more satisfying than most of the items actually discovered.
The direct entertainment value can also be high. Web sites such as Warner Brothers and Disney provide film clips. Adam is also fond of looking for stories, pictures and cartoons, some of which he downloads and saves in his own folder on our Mac.
Much of the Web material designed for children is obviously intended to be educational in some sense, but a lot of it is too sophisticated for a five-year-old. For example, Sea World in California has a wonderful array of quizzes and factual material that went straight over Adam's head. We tried also the quiz that matches mystery noises to the appropriate creature, but - aside from the extreme slowness involved in downloading sound - were frustrated by his basic lack of experience of sea animals.
He was fascinated by an Internet frog dissection, until it got a bit too graphic. ''I didn't like it with all its skin off and asked Daddy to put it back on.''
We ended our session by looking for a picture of the Sphinx, to explain the storyline in his current bedtime book, Asterix and Cleopatra. In the book, Obelix breaks off the Sphinx's nose, so we wanted a picture showing that indeed it has no nose in real life. We failed, but settled for a picture of the Great Pyramid.
The broader educational point is that a lot of the material Adam sees as we browse prompts him to ask all sorts of questions. We sat down at the computer on one of the days when many home pages were coloured black with blue ribbons to protest at the US government's bid to censor Net material.
We tried to give Adam a simple explanation of the free speech arguments for five-year-olds - without, of course, telling him about pornography. This is difficult: if you do not spell out what is so bad, it is hard for a child to understand why anyone might want to introduce censorship.
We told him the blue ribbon campaign was a Good Thing. I am not too worried about him downloading pornography off the Net, either now or when he gets older. Pornography is to be found in the newsgroups, and, my husband assures me, would be very difficult for Adam to find by accident now.
As for later, when boys reach a certain age they start to try to lay their sticky hands on rude pictures, and the modem is just another means of distribution. If we kept him off the Net when that time comes, he would no doubt go to a friend's house or make a furtive purchase from the top shelf at the newsagent.
After our free-speech discussion, Adam brought our Internet session to a speedy end. ''I'm getting bored. We haven't found a single game that was very interesting,'' he announced. And he carefully disconnected the line before trotting off to the old-fashioned pleasure of Asterix.
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