It is a work of prodigious detection through the scant records of British censuses, clues, letters and photographs with cryptic captions on the back.

My sister, Cordelia Mary Davison Hull, found the identity of the biological father and mother of my father against a backdrop of cover-up, deceit, prudery and middle-class snobbishness.

Her diligent work of historical discovery makes me wonder about how the internet and the attitudes it has engendered among its almost universal users might be at once a blessing and a curse for someone in the future engaging in such a task.

Once the vast databases from the British censuses and from the registries of births, death and marriages of the early 20th century were made available online, the task of the genealogist in Britain and what is now the Commonwealth became far easier.

The internet has changed our written communications with each other.

Email has replaced mail. That has enabled the group letter to be produced more easily, but my guess is that it has almost killed the detailed regular weekly correspondence of old.

Bundles of letters kept over years used to be fairly commonplace. Now emails end in the delete folder. Moreover, the ease and immediacy of email has meant their contents are more practical and trivial and less introspective and comprehensive.

Much is made of the ease with which personal information can get bandied about the internet, and that once something is out there you can never get it back.

Material about youthful antics and idiocies casually put up on Facebook might well come back to haunt those who put it there when they seek responsible positions later in life.

But, conversely, a lot of this material is unverifiable and can be taken down as easily as put up.

My guess also is that later historians will find large gaps in information from the early 1980s to around the end of the 1990s.

This is when storage on the personal computer became possible. But space on computers was scarce then, and so a lot of information was casually discarded which in bygone days would have been filed on paper.

Incidentally, Cordelia found society's fundamental misogyny a major hurdle. Women before recent decades universally changed their surnames upon marriage, making it difficult to trace their origins from their married names.

Unusual male surnames make the genealogist's task easier.

But the most profound effect the internet will have on genealogy is to make it more popular.

My sister started her task because there was a profound mystery about my father's immediate ancestry. An abiding curiosity overcame the obstacles of pre-internet searching - hard work and many disappointing dead ends. These days the internet makes at least the initial results easy to obtain and has thrown up a trade of money-making middlemen to spawn a whole new industry.

But most Anglo-Celtic searchers are unlikely to trace their family back much beyond pre-industrial Britain.

■ ■ ■ Last week's column did not appear on Saturday as usual because of an internet glitch but was published on Tuesday. Some astute readers have picked up an obvious omission.

In writing about compulsory voting I observed that nearly all our duties and responsibilities in a democracy were of the kind ''if you do this then you must do that''.

If you want to drive you must drive on the left. Few duties in Australia were absolute, I wrote, other than the duty to vote and in bygone times to be called up for military service.

On the basis of the conscriptive nature of compulsory voting, I argued against it.

Several readers have rightly pointed out that jury duty is also an absolute duty.

They are quite right and I can only plead Januaryitis for omitting the fact.

As it happens, it strengthens the original argument. Jury duty, like military service and compulsory voting, shows the evil of civil conscription.

Randomly choosing 12 people to evaluate often-complex evidence and decide whether a person is guilty or not guilty is manifest folly. Moreover, a system in which the chosen 12 do not have to give reasons for their decision makes it worse.

We all know the dramatic tension used by writers of legal and crime thrillers as the jury files in to give its verdict. At that stage, it could go either way. That is an indication of the haphazard, luck-dependent nature of the system.

But once it has gone one way or the other the decision is vested with an almost religious aura of correctness.

Yet juries mess it up all the time and those affected (the wrongly convicted) or society as a whole in cases of mistaken acquittal have no recourse because the jury does not have to give reasons and is unaccountable for its decision.

No other decision-making process in our democracy has these flaws - precisely because no other decision makers are conscripted.

Oddly enough, most lawyers and judges praise the jury system. Maybe that is because of their innate conservatism or perhaps it relieves the burden of having to make quick decisions themselves.

Counter to that, most military people think that conscription is a waste of time and defence is better left to the professional soldiery. Unwilling soldiers have no place in the technology-rich modern military which has far less use for cannon fodder.

Another compulsory duty I did not mention last week was the filling out of the census form.

I have no argument against it because the census would not work without universality and compulsion, whereas the elections, the legal system and the military would.

Whether a soldier, jury member or voter, the conscripted are bound to be more resentful, less diligent and do a worse job than the engaged volunteer or professional.

Crispin Hull is a commentator, author and former editor of The Canberra Times.

www.crispinhull.com.au