Like many other pagan monuments, they may have been consecrated by having the sign of the cross engraven on them hundreds of years after their erection.
During the few months which have elapsed between the appearance of the first edition and the preparation of the second edition, my attention has been called to this portion of the history by four or five eminent members of the Royal Irish Academy, who express their regret that I should appear to have adopted, or at least favoured, Mr.D'Alton's view of the Christian origin of the round towers.

I cannot but feel gratified at the interest which they manifested, and not less so at their kind anxiety that my own views should accord with those of the majority.

I am quite aware that my opinion on such a subject could have little weight.
To form a decided opinion on this subject, would require many years' study; but when one of these gentlemen, the Earl of Dunraven, distinguished for his devotion to archaeology, writes to me that both Irish, English, and Continental scholars are all but unanimous in ascribing a Christian origin to these remarkable buildings, I cannot but feel that I am bound to accept this opinion, thus supported by an overwhelming weight of authority.

It may, however, be interesting to some persons to retain an account of the opposing theories, and for this reason I still insert page 115 of the original edition, only making such modifications as my change of opinion make necessary.
The theories which have been advanced on this subject may be classified under seven heads-- (1) That the Phoenicians erected them for fire temples.
(2) That the Christians built them for bell towers.
(3) That the Magians used them for astronomical purposes.
(4) That they were for Christian anchorites to shut themselves up in.
(5) That they were penitentiaries.
(6) That the Druids used them to proclaim their festivals.
(7) That the Christians used them to keep their church plate and treasures.
[Illustration: URN AND ITS CONTENTS FOUND IN A CROMLECH IN THE PHOENIX PARK, DUBLIN.] Contradictory as these statements appear, they may easily be ranged into two separate theories of pagan or Christian origin.

Dr.Petrie has been the great supporter of the latter opinion, now almost generally received.