WE don't know who the anonymous artist was who painted the 1800 watercolour of Bootham Bar which we start off with here. But we have a lot to thank him for.

He painted the bar at a time when it still had its barbican, for one thing. And he also captured some long-vanished buildings that used to lean up against the bar - some of them with beautifully carved details around the windows.

Look at the painting long enough, however, and you might begin to think you're seeing things. It was painted from outside the bar, looking through the arch towards Petergate, with the Minster looming behind. But isn't the cathedral in the wrong place?

Well, yes. That's because the painting is a mirror image. This wasn't, apparently, all that uncommon. Many artists used to paint from mirrors - it helped to 'frame' the subject, as David Hockney points out in his wonderful book A History of Pictures. But it also, of course, meant the finished paintings were back to front...

The Minister is in its rightful place with relation to the bar in Thomas Shutter Boyes's slightly later watercolour, painted after 1835. The barbican had been removed by the time Boyes painted his picture: so as well as being the right way around, his bar looks more familiar to the modern eye.

The bar was painted again in about 1920 by Noel Harry Leaver, this time from Exhibition Square. Though much of what can be seen in Leaver's painting is familiar to us today, the cobbled street and the brown tones of the painting give it a much more rural feel than it has now. Leaver's painting shows essentially the same view as can be seen in an 1870 photograph and a modern photograph also reproduced on these pages. The 1870 picture is notable for the cobbled streets, the ornate Victorian lamps - and the row of horse-drawn cabs waiting at a taxi rank on the far side of the square.

The cobbles, taxi rank and lamps had all survived to 1920, when Leaver painted his watercolour - he includes a taxi cabin (though there's no sign of cabs, horse-drawn or otherwise) and a lit lamp in his painting. Today, these have all gone. Exhibition Square is paved, and lined with benches, a phone box and a post box.

All these images come from The Streets of York: Four Centuries of Change, a new book published last week to support local charities which brings together 200 or so original paintings, many quite old, with old and new photographs to show how many of York's best-loved streets have changed (or in some cases not changed) down the centuries.

The series of images of Jubbergate - an 1885 watercolour by John England Jefferson; a 1910 photograph; and a modern photograph - comes from the same book. The three images show the same view of Jubbergate. In Jefferson's watercolour, the tower of Christ Church in King's Square can clearly be seen looming in the background. The tip of the tower can also just about be made out in the 1910 photograph, if you look closely enough. It was long gone by the time the modern photograph was taken, however. The ancient timbers of the building in the foreground (now Gert & Henry's) have also been exposed in more recent years, giving the building a very different look to the rather run-down appearance it had 100 or so years ago.

Stephen Lewis

The Streets of York: Four Centuries of Change by Darrell Buttery, Ron Cooke, Stephen Lewis and Chris Shepherd is published in hardback by York Publishing Services, priced £30. An exhibition based on the book opens next Wednesday (October 31) at the Maclagan Hall in St Williams College. Public admission will be every weekday afternoon from 2.30pm to 4.30pm, entry £12 on the door. All proceeds from both the book and exhibition will be shared between York Against Cancer, York Civic Trust and the York Minster Fund.

The book is available from Fairfax House, the Minster bookshop, York Against Cancer shops and The Press offices in Walmgate. Please note: if planning to buy from The Press, only cash or cheques (payable to York Publishing Services Ltd) can be accepted.

The book is also available direct from York Publishing Services on 01904 431213 or from YPDbooks.com for £30 plus £3.60 p&p, or can be bought at the special discount price of £20 by anyone visiting the exhibition.