[tz] Historical discrepancies for Italy.

[Michael H Deckers]

    On 2016-10-24 15:59, Pierpaolo Bernardi wrote:

>  This page http://www.renzobaldini.it/le-ore-legali-in-italia/ has
>   still diferent data for 1944.
>
> It divides Italy in two, as there were effectively two governments at
> the time, north of gotic line
> (https://en.wikipedia.org/wiki/Gothic_Line) German controlled
> territory, official government RSI
> (https://en.wikipedia.org/wiki/Italian_Social_Republic), and south of
> gothic line, controlled by allied armies.
>
> Data for neither of the two zones agrees with INRIM, as far as I can
> tell from a cursory examination.
     Yes, this has puzzled me. It turns out that the INRiM page is wrong
     for both changes in 1944: the switch they give for summer time is 
the one
     obeying C-Eur Rules and was applied in RSI but not south of the 
Gothic line;
     the switch to winter time on Sep 17 went from 03 to 02 h, not from 
02 to 01 h
     as given by INRiM:
        -Rule    Italy   1944    only    -       Apr      3 2:00     
1:00    S
        +Rule    Italy   1944    only    -       Apr      2 2:00     
1:00    S
        +Rule    Salò    1944    only    -       Apr      3 2:00     
1:00    S
        -Rule    Italy   1944    only    -       Sep     17 2:00     
0       -
        +Rule    Italy   1944    only    -       Sep     17 3:00     
0       -
        +Rule    Salò    1944    only    -       Oct      2 3:00     
0       -
     The source
          [http://www.ac-ilsestante.it/MERIDIANE/ora_legale/
          ORA_LEGALE_ESTIVA_IN_ITALIA.htm]
     is correct.

     The correct switches applying in Rome (in the "regno") in 1944 can 
be looked
     up in [augusto.agid.gov.it/gazzette/index/download/id/1944062_P1S.pdf]
     on page 374, DECRETO LEGISLATIVO LUOGOTENENZIALE 14 settembre 1944, 
n. 219:
          ....
          Visto il R. decreto-legge 29 marzo 1944, n. 92, col
          quale l'ora normale è stata anticipata di sessanta mi-
          nuti primi a partire dalle ore due del 2 aprile 1944;.
          [Considering the royal law-decree 1944 March 29, n. 92, by which
           standard time has been advanced by sixty minutes from
           1944 April 2, two hours]
          ....
          A partire dalle ore tre del giorno 17 settembre 1944 é
          ripristinata l'ora normale.
          [From three hours on the day 1944 September 17 standard
           time is resumed.]

     The text goes on to explain that the jump causes the hours
     from 02 h until 03 h to be repeated, so that we can be certain that
     a jump from 03h to 02 h is implied. One could even argue that
     the text implies that 02:00 is assumed twice but 03:00 is not
     (so that the time scale is a right continuous function of UT).
     The decree was issued in Rome on 1944-09-14 (very short notice!)
     and signed UMBERTO DI SAVOIA.

     The corresponding switch in the RSI can be looked up in
[http://augusto.agid.gov.it/gazzette/index/download/id/1944229_P1_GI.pdf]
     on page 1512. It uses the C-Eur rules and is signed MUSSOLINI.

     Nice history lesson!

     Michael Deckers.