[tz] Hong Kong time 1941
Michael H Deckers
michael.h.deckers at googlemail.com
Sun Nov 18 21:43:22 UTC 2018
On 2018-11-18 20:04, Paul Eggert wrote:
> However, Hong Kong switched at 17:00 UT so if the intent was for Macau
> to keep in lock-step with Hong Kong, the Macau transition should be at
> 17:00 UT.
But we simply do not have any evidence that "Hong Kong switched at
Steve Allen has shown that the documents available for Hong Kong only
that the time ball was flown (and a cannon was shot) when UT was
(and GMT was 1904-10-29T17). That happened 12 h after your proposed
of Hong Kong time to UT + 08 h. We just do not seem to have any new
evidence for the switch of Hong Kong time in 1904.
But we do have evidence that Macau switched to UT + 08 h when UT was
1904-10-29T16 (tzdb currently says, 1904-10-29T16:23:18), and
that they did that in order to achieve a common time scale with the
neighboring parts of China.
I do not want to pester the list with my quibbles about your proposed
changes, and this will be my last post on this issue -- I just want
to make sure that tzdb makes the most proficient use of the aggregated
knowledge of the people in this list.
Portaria N° 204 of 1904-10-21 for Macau was announced by P Chan on
and it was rightly noted in tzdb that this indicated the switch to a
time scale with Hong Kong. The new documents for Hong Kong do not
change this view (otherwise the text of tzdb would have to be corrected
anyway). For all we know, it is likely that Macau and Hong Kong switched
to UT + 08 h at the same instant (and that instant most likely was when
UT was 1904-10-29T16).
More information about the tz