[tz] Irish time...

David Malone David.Malone at nuim.ie
Sun Oct 16 19:34:09 UTC 2011

> Europe/Dublin  Sun May 21 02:25:20 1916 UTC = Sun May 21 01:59:59 1916 DMT isd
> Europe/Dublin  Sun May 21 02:25:21 1916 UTC = Sun May 21 03:00:00 1916 IST isd
> Europe/Dublin  Sun Oct  1 02:25:20 1916 UTC = Sun Oct  1 02:59:59 1916 IST isd
> Europe/Dublin  Sun Oct  1 02:25:21 1916 UTC = Sun Oct  1 02:25:21 1916 GMT isd

> That is, the clocks went forward one hour at 2am DMT on 21 May, and then 
> at 2am DMT (3am summer time) on 1 October they went to GMT.  See attached 
> scans of the relevant laws.

My understanding is similar to this: we had both summer time and
then later a switch to GMT in 1916. This is based on the two acts
that you attached. I has started searching the newspaper archives,
but I seem to have skipped 1916 and gone on to the 1940s to look
for information about double summer time, which we didn't have, but
Belfast did (see the note transcribed from the Irish Times below -
it was followed on subsequent days by notices about differences in
train times, radio schedules, etc...)

> The relevant UK National Archives file has a public information poster 
> used in Ireland to inform people of the 35-minute clock adjustment.  What 
> times people were actually using in Ireland, I don't know.

I'd be interested to see this, if you have a copy.

> I have not attempted a thorough survey of Irish laws relating to time; my 
> 2005-01-26 comment in the europe file lists those I found (though those 
> URLs seem to have become broken since then) but I haven't attempted to 
> match them up to individual transitions and add comments for each 
> transition giving the Irish legal basis for it alongside those giving the 
> British basis.

I did a check a few years ago, probably after 2005, and found very
little relating to time, other than SIs implementing EU directives.
We did do a cleanup by scrapping old statuates recently, and I
skimmed it for time related acts. There was one "On the Measurement
of Time", but when I checked, it was a transcription error and it
was really "On the Measurement of Lime".


Saturday, April 4, 1942
Double Summer Time

Double British Summer Time, which applies also to Northern
Ireland, begins at 2 a.m. to-morrow by the clock, which is
already one hour in advance of greenwich mean time. Clocks
are put forward one hour. Double Summer Time ends on Sunday,
August 9th.

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