I was surprised to find phrases in the Lick web pages:  "CCIR ignored the 
advice that astronomers " and "squelched astronomers who insisted that leap 
seconds would cause trouble".   

I realize their author is not the only person with a strong emotional bias, but 
even so I question the tone of these web pages because they are inconsistent 
with the following:

1. There was a progression in thought as technology advanced and atomic clocks 
proved their reliability.

2. It should be obvious that ephemeris time would need a flywheel system to get 
practical time to the users, and GMT could be part of that.  Today individual 
labs realize UTC(k) for the same reason - to flywheel before the monthly 
computations of UTC are published.  WWVB, GPS, and your local cell towers are 
all part of the system as well.  (Even so, I think everyone today agrees that 
Ephemeris time was a mistake.)

3.  According to references in Nelson et al’s Metrologia article, which was 
peer-reviewed, it looks to me like the switch to UTC was by universal agreement 
among the institutions.  The IAU, URSI, CIPM(=CGPM), and CCIR(= ITU) all agreed 
to the current system in the late 60's, and I would guess that the timing of 
their resolutions probably depended more on the (generally) 3-year spacing of 
their general assemblies than anything else.  Note that many of those groups 
had overlapping membership.  It would however be unusual if all individual 
members of these bodies ever agreed to any resolution, even if passed "by 
consensus".

For more trivia, the dynamic  Gernot Winkler of the USNO was both a practical 
clock man and astronomer.  He was not the only one, and he was a very active 
member of the IAU who chaired commissions, served on working groups, etc.  He 
told me personally that he and Essen independently came up with the idea of 
leap seconds.   He also said a big reason was to win the support of the 
mariners, who in the pre-GNSS days actually did celestial navigation and who in 
the pre-internet days could not easily get access to tables that incorporated 
the difference between UT1 and UTC.


________________________________________
From: LEAPSECS [[email protected]] on behalf of Steve Allen 
[[email protected]]
Sent: Wednesday, March 14, 2018 12:16 AM
To: Leap Second Discussion List
Subject: [Non-DoD Source] [LEAPSECS] D.H. Sadler in 1954

In 1954 D.H. Sadler produced a monograph on the changes in time
that had been resolved at the 1952 IAU General Assembly.
His writeup is clearer than almost anything else for the next 60 years.
It was published in Occasional Notices of the RAS, and it has been hard
to find until now.
https://www.ucolick.org/~sla/leapsecs/twokindsoftime.html
This is one of the series of documents produced starting in 1948 and
proceeding through the next 20 years where astronomers explained that
two kinds of time would be needed to satisfy all applications.

--
Steve Allen                    <[email protected]>              WGS-84 (GPS)
UCO/Lick Observatory--ISB 260  Natural Sciences II, Room 165  Lat  +36.99855
1156 High Street               Voice: +1 831 459 3046         Lng -122.06015
Santa Cruz, CA 95064           http://www.ucolick.org/~sla/   Hgt +250 m
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