To paraphrase Sean O'Casey, what are the stars and what are the stones? Well, the stars are sidereal and the stones the decorated ones of the Boyne Valley. Martin Brennan has had a 10-year love affair with both and the result is this controversial book; he makes one statement, however, with which I think everyone who has an interest in these matters will agree: "It is odd that this art (ancient Irish art) which represents the first major western European art tradition had managed to remain obscure and relatively unknown." It is strange indeed.

When I first came across Newgrange during the war years I had known vaguely of its existence but was greatly impressed when the caretaker, a Mr Hickey, showed me around. At that time, there was a locked gate to the place but there was no electric light and we had to use candles to see the interior. While all of Mr Hickey's observations may not have agreed with modern archaeological opinion and knowledge, he was and entertaining and enthusiastic guide and he was adamant that at the time of the mid-winter solstice, the sun shone in through the narrow entry to the inner chamber. Indeed, so impressed was I by his statement that I arranged to meet him there one December solstice dawn and started to cycle to it, only to skid so many times on the icy road that I had to turn back.

Things have, of course, changed since then but while there is definitely growing interest in Newgrange and we now have the late Professor Michael J. O'Kelly's fine book on the subject, there is all too little realisation generally about the wonders of the Boyne Valley. Knowledge of it seems confined to scholars and enthusiasts ­ of course, one could take a selfish view and be glad that it is not as visited and as spoiled as Stonehenge. We have a wonder on our hands, within and hour's drive or so of half the population of this island. Much more money needs to be spent to encourage the hardworking and dedicated archaeologists who have worked so unselfishly there in the dank insides of the tombs to unravel the mysteries. Their enthusiasm has had no practical award

Now Martin Brennan is equally enthusiastic, but he contends that the real story of the Boyne Valley and the nearby Loughcrew Mountains is much more complex and fascinating than merely the buildings there and the shaft of light at Newgrange. He believes that there is a complex of mounds mainly in the Boyne valley and at Loughcrew which are orientated to the rising and to the setting of the sun at various times of the year at equinoxes and cross quarter days; furthermore he is convinced that he has proved it. If this is so ­ and it is difficult to refute his evidence ­ unless one goes along and waits for the shafts of light at appropriate times in the year and with our climate, one might have to wait a number of years at that. It has indeed taken Martin Brennan a number of years and the assistance of some 28 people to make his observations.

He tells us something about himself in this book and it does throw some light on what he is doing. He is from New York though of Irish parentage, and his training has been in visual art. After three years' study on prehistoric art in Mexico and a similar period in Japan, he was drawn to Ireland and to the Boyne Valley specifically. His training in art research did not allow him to accept that there was not a pattern of meaning to what appeared to be abstract drawings. "The suggestion of solar and lunar images and the presence of actual sundials in the engravings, coupled with the spectre of the light entering Newgrange and the tremendous weight of tradition meant that all the needles were pointing in one direction" ­ that was, to a close matching of the passage mounds to the movements of the sun and of the moon at the latitude where the buildings were. He did not arrive at this concept lightly; he had been here for six years before reaching this tentative surmise.

A thorough man, he created Neolithic sundials to advance his theories a (a feat in itself, as there are no actual models to work on and there were no textbooks to guide him). He found "another artist and amateur astronomer," Jack Roberts, and together they began an exciting piece of direction. Up in the small hours of the morning, they trekked to catch the fleeting sunrise, often to be foiled by cloudy weather and occasionally by a car breakdown: "we felt we were 10 minutes late for and appointment made over 5,000 years ago."

Then the sun did shine for them, after many weary hours in the dark recesses of the mounds on the Loughcrew Hills and for the first time "we were seeing the signs and symbols in the context in which the artist meant them to be seen. Suddenly markings that had appeared to be random and haphazard became part of an intricately structured system that derived its meaning from the solar event we were witnessing." Among others of Martin Brennan's finds are that on the day of the winter solstice, while the sun projects its rays into Newgrange at dawn, it happens at sunset at Dowth, apart from the winter and summer solstice, that is.

Now, Martin Brennan, to put it mildly, is not all that friendly with archaeologists. He is at one with John Mitchell, author of Megalithomania that archaeologists are "ill-equipped to investigate the stone instruments of the earlier, more comprehensive system, whose secrets cannot be investigated along with the bones and potsherds." Archaeologists maintain that the great complex was a collection of tombs and are sceptical of the existence of a chronological linking between the mounds. Yet I think it fair to say that Martin Brennan's book would raise a doubt or two in anyone's mind.

It is, I believe, a further wonder if the buildings were not thrown out of alignment by the recorded earthquakes and tremors in the region (and if this were so, it would cast doubt on the theories in this book). Doubt upon doubt there may be, but serious consideration will have to be given to a view so eloquently argued. The buildings at Newgrange, Dowth and Knowth are extraordinary creations and impressive though recent research has been, there remains a lot to be investigated before a definite conclusion can be drawn. They are among the great early structures of mankind and argue and advanced and sophisticated civilisation. (It must be further said, that the economy that funded them must have been a thriving one.)

In addition to the text, there are over 100 pages of drawings to scale of the various stones to be found in the Boyne-Loughcrew complex, with Martin Brennan's explanations, in what, I must term and exciting and fascinating book.

Boyne Valley Private Day Tour

Immerse yourself in the rich heritage and culture of the Boyne Valley with our full-day private tours. Visit Newgrange World Heritage site, explore the Hill of Slane, where Saint Patrick famously lit the Paschal fire. Discover the Hill of Tara, the ancient seat of power for the High Kings of Ireland. Book Now