Status: Believed to be a hoax
Here's an interesting news report
It has emerged that a joke bronze plaque found on Dublin's O'Connell Bridge has been there for three years. The plaque claims to mark the spot where a Father Pat Noise drowned when his carriage plunged into the Liffey, in suspicious circumstances, in 1919. But Dublin City Council says the priest is a fictitious figure, and wants the mystery sculptor to come forward. The plaque is arousing great public interest, and flowers and candles have been left on the bridge in memory of "Father Noise".
The Irish Sunday Tribune (no link) has a few more details:
The plaque, which even contains a picture alleging to be that of the mysterious religious figure, claims to mark the spot on which Fr Noise died "under suspicious circumstances when his carriage plunged into the Liffey on August 10th, 1919." The plaque states that Fr Noise was an "adviser to Peader Clancey."
After being informed by the Sunday Tribune of the plaque's existence, council officials inspected it on Friday afternoon and hope to identify when and how it was placed into a hole on top of the wall on the bridge. The plaque is located on the Ha'penny Bridge side of O'Connell Bridge, near to the traffic lights on Bachelor's Walk.
The plaque claims to have been erected by an organisation called "the HSTI", although the heritage department of the city council said it had never heard of a group by this name.
"Council officials had a look at the plaque (on Friday) but they said they had never seen it before," said a spokeswoman. "It is certainly very unusual for this to happen."
The council said that it was possible the plaque was erected legitimately a number of years ago, although this would seem most unlikely given that nobody seems to have noticed it until last week.
The rough manner in which the plaque is inserted into the wall would also suggest that it was placed only recently. Although it appears expertly made, it is too small for the hole, which has several rough edges.
Council officials will now attempt to pinpoint the age of the plaque and the historical significance of 'Fr Pat Noise' before making a decision on whether or not to remove the memorial.
Unfortunately I haven't been able to find any pictures of this plaque.
[Update:] Here's a picture
of the plaque, though it doesn't let you see it very well.