Things have changed dramatically since Great-Grandad Fred opened the garden gate at Pendleton House to the 1901 census enumerator, but the present occupant courteously suggests that the genius loci is the same.

"Perhaps there is a blessing on this place," says Shah Khan, the chairman of the Leeds Islamic Society whose trustees filled in the census form last year, a century after Frederick White, manufacturing chemist, and his family were carefully noted down.

Churchgoers all - and about to marry into the strongly Methodist tribe of Wainwrights who lived 200 yards along Spencer Place in Chapeltown, Leeds - they would surely approve that their home has become a religious institution, says Dr Khan.

Different sons and daughters of Abraham maybe; but the city's newest, beautifully decorated mosque looks good in the front garden, where great-grandad and the enumerator no doubt admired the first daffodils of late March.

Elegantly listed, the Whites appear in relatively skeletal form on the 1901 census's standard page, compared with the detail of the family photo taken a year or two later on the steps of Pendleton House.

The form reassures that none of them was deaf, dumb, blind, lunatic, imbecile or even feeble-minded, but its other revelations are humdrum: Fred's date and place of birth (May 27 1857, Leeds), his age, profession and position in the family (no two ways about that: he told the enumerator to write down "Head").

But while scrolling along Spencer Place, the comfortable world of bourgeois "New Leeds", as Chapeltown was known in those days, does begin to emerge from 100 years' mist.

Here are the Blackburns, whose aircraft factory in Roundhay Road is now a Tesco; and here is Henry Scurrah Wainwright, whose marriage to Sissie White was soon to be toasted inmarquees on the lawn where mosque-goers' children now tumble about.

Massive overuse curbed further census-surfing yesterday, but not before one advantage of online genealogy had become clear.

Last time I went on the trail of great-grandad, the area was a notorious kerbcrawling zone. My fieldwork had been jinxed by fears that the excuse "But officer, I'm just trying to find out where granny got married" would not wash.