So, an unusual piece of legislation is passed and 58 years later
prices fall dramatically in a single spot in rat-infested, decaying, and diseased 19c Dublin? (Let's leave aside the small matter of the population dropping 25% during the 1845-1852 famine).
I assume, since you're posting this in the PIN, you have some comparsion to make with today's property prices, but it escapes me at the moment. Are you calling for the deaths of over 1 million people just so you can gets your hands on a house?
p.s. I assume your original post meant the Act of Union of 1801
Well, now, a lesson on the Irish economy, demographics and property prices from history.
The direct impact of the Act of Union (whether you pick 1800 or 1801) was to reduce the importance of Dublin politically, which had knock on effects both economically and socially. Post the Act, the Irish political classes migrated from Dublin to London. Many of these individuals were merchants, so their business and money went with them; a 19th Century Brain Drain if you will. This in turn reduced the mercantile and commercial activity in the City with knock on effects into (what then passed for) the wider economy. Once grand Georgian houses that had sprung up to offer "aspirational living" fell into decay and were subdivided into the tenements that became a feature of Dublin until very recently (The York Street buildings only being vacated and demolished in this decade).
As the Act cemented Ireland as part of the United Kingdom, Dublin and Ireland in general slipped down the global commercial pecking order and was reduced to the same level of importance within the UK as any other provincial district (all be it a from time to time more disruptive one). The effect of this was to further reduce commerce, further deepening the economic contraction and collapse of property prices.
All this before the catastrophe of the famine years, from which, 160 years later, the population levels have not yet recovered.
Are there any lessons for today from what happened in the 19th Century? While we can't draw direct parallels, I believe, looking back, there are a couple of broad themes we can see;
First off, as some people are only learning now, but most pinsters already knew, Irish property can go down just as dramatically as it went up (all be it that the example here is rather extreme).
Secondly, economies, especially our small peripheral one, can be affected directly by external factors. We're not likely to be reduced to provincial status again, but, we have already seen the effects of the external shock that the global banking crisis has had here. Other external events could negatively impact on us too. For example, should the US pass legislation to chase the Transfer Pricing activities of US HQ'd companies here or perhaps a significant conflict involving NATO somewhere on the globe (how many NATO members are in the Euro Zone?).
Third, the Irish have a long tradition of migration. Whether the motivation was economic, conflict, lifestyle or just survival, a significant proportion of the population of this little island is more than willing to up sticks and move elsewhere which could significantly undermine the viability of the economy.