Some more details from the pneumatic clocks in Paris in 1880:
(Sorry for the g00gle-style translation)

In "Le Magasin Pittoresque" in 1880, we can read an article entitled "Unification of time on the electricity and compressed air".

Regarding the pneumatic clocks, we read "... Already clocks operating with this new system, invented by Mr. Popp from Vienna, have been installed in Paris ...
A central clock is setup so that whenever the pendulum hits the sixtieth second of a minute, there is a trigger switch that delivers the compressed air in containers, it rushes immediately into the tubes of the network, and inflate a bellows which is at their end. By blowing, the bellows raises a small lever that rotates one step in a wheel that has sixty, and each corresponding to one minute. At the same wheel is set the minute hand Dial moving a minute ...
The installation of the first fifteen dials required eighteen kilometers of pipes, and their establishment is such that all the people who live near the pipeline network that can receive time at home. It is sufficient to hook a small diversion conduct on the central pipe that brings home the compressed air provided by the administration. "

In another part, I read that the pressure pulse is maintained during the 21 first seconds of each minute.

Also I found a couple of pictures from such public clocks installed in the streets.
http://www.casimages.com/img.php?i=090312075720411213302119.jpg
http://www.casimages.com/img.php?i=090312075720411213302120.jpg

-Marc-

That's good data on the pulse time, Marc. I suppose a one-second pulse
would be severely attenuated by a kilometer of pipe.

Interesting that the first image, Air17, shows a clock at 1:50. This is
now universal for watch and clock advertising, for analog dials.

Bought the Hahl clock on eBay (thanks, Russell). The bellows has
deteriorated, but I have some experience with player pianos. Looking
forward to seeing what it needs. Also have an 1879 print from Scientific
American coming that shows the workings of a pneumatic clock.

Bill Hawkins

-----Original Message-----
From: Marc Bury
Sent: Thursday, March 12, 2009 2:04 AM

Some more details from the pneumatic clocks in Paris in 1880:
(Sorry for the g00gle-style translation)

In "Le Magasin Pittoresque" in 1880, we can read an article entitled
"Unification of time on the electricity and compressed air".

Regarding the pneumatic clocks, we read "... Already clocks operating
with this new system, invented by Mr. Popp from Vienna, have been
installed in Paris ...
A central clock is setup so that whenever the pendulum hits the sixtieth
second of a minute, there is a trigger switch that delivers the
compressed air in containers, it rushes immediately into the tubes of
the network, and inflate a bellows which is at their end. By blowing,
the bellows raises a small lever that rotates one step in a wheel that
has sixty, and each corresponding to one minute. At the same wheel is
set the minute hand Dial moving a minute ...
The installation of the first fifteen dials required eighteen kilometers
of pipes, and their establishment is such that all the people who live
near the pipeline network that can receive time at home. It is
sufficient to hook a small diversion conduct on the central pipe that
brings home the compressed air provided by the administration. "

In another part, I read that the pressure pulse is maintained during the
21 first seconds of each minute.

Also I found a couple of pictures from such public clocks installed in
the streets.
http://www.casimages.com/img.php?i=090312075720411213302119.jpg
http://www.casimages.com/img.php?i=090312075720411213302120.jpg

-Marc-

Just noticed this.....FYI....
Not sure how this fits in with eLORAN efforts.

The Operating Status of LORAN-C

LORAN-C provides coverage for maritime navigation in U.S. coastal areas. It provides navigation, location, and timing services for both civil and military air, land and marine users. LORAN-C is approved as an en route supplemental air navigation system for both Instrument Flight Rule (IFR) and Visual Flight Rule (VFR) operations. The LORAN-C system serves the 48 continental states, their coastal areas, and parts of Alaska.

On February 26, 2009, the Office of Management and Budget (OMB) publicly announced the President's Fiscal Year 2010 Budget. In the section for the Department of Homeland Security, the budget "supports the termination of outdated systems such as the terrestrial-based, long-range radionavigation (LOrAN-C) operated by the U.S. Coast Guard resulting in an offset of $36 million in 2010 and $190 million over five years." For more information on the proposed FY2010 Budget, visit the OMB website under President's Budget.

The Coast Guard will continue to operate the current Loran C system through the end of FY2009 and is preparing detailed plans for implementing the FY2010 Budget.