An excellent summary, thanks, a worthy read. At 05:59 PM 9/7/2011, time-nuts-request@febo.com wrote: >Message: 1 >Date: Wed, 07 Sep 2011 10:27:26 -0700 >From: Mike Fahmie <mpfahmie@lbl.gov> >To: <time-nuts@febo.com> >Subject: [time-nuts] From Sundials to Atomic Clocks >Message-ID: <4.3.2.7.2.20110907101956.0388f5f8@popper.lbl.gov> >Content-Type: text/plain; charset="us-ascii"; format=flowed > >On a visit to NIST Boulder (then known as NBS) many years ago (1978), I was >presented with a copy of NBS Monograph 155, "From Sundials to Atomic >Clocks" by one of the authors. I found it to be a fantastic read, it >answers all of those questions about Time & Frequency that you were afraid >to ask. > >I stumbled on it again today in PDF form on the NIST website, it has >undergone two revisions and this URL points to the most current >(1999) edition. > >http://tf.nist.gov/general/pdf/1796.pdf > >-Mike- >WA6ZTY Sincerely, Marv Gozum Philadelphia, PA