What's the correct time zone before time zones

Question

What's the correct time zone offset for "Januray, 1st 1000" for a Java program running in Zurich?

Background: When I use joda-time 2.1,

new DateTime( 1000, 1, 1, 0, 0, 0, 0, DateTimeZone.forID( "Europe/Zurich" ) ).toString()

gives me

1000-01-01T00:00:00.000+00:34:08

which seems odd because of the time zone offset 00:34:08 (an 34:08 minute offset??). Looking into the europe entry in the IANA Timezone Database, I see this:

# Zone  NAME            GMTOFF  RULES   FORMAT  [UNTIL]
Zone    Europe/Zurich   0:34:08 -       LMT     1848 Sep 12
                        0:29:44 -       BMT     1894 Jun # Bern Mean Time
                        1:00    Swiss   CE%sT   1981
                        1:00    EU      CE%sT

This gives all times before Sept. 12th, 1848 an offset of 34:08 which doesn't seem right.

Can someone shed some light on this?

Answer 1

Wikipedia, on European time zones:

1894

• Switzerland switches from UTC+00:30 to CET
• Liechtenstein introduces CET.
• Denmark adopts CET.

I suspect the leftover seconds are compensatory changes that have been made since 1894, leap seconds and the like.

Answer 2

From here

Interestingly, many French maps showed zero degrees at Paris for many years despite the International Meridian Conference’s outcomes in 1884. GMT was the universal reference standard – all other times being stated as so many hours ahead or behind it – but the French continued to treat Paris as the prime meridian until 1911. Even so, the French defined legal time as Paris Mean Time minus nine minutes and 21 seconds. In other words, this was the same time as GMT

(my emphasis)

So I suspect Paris was not the only European city to act in this fashion