Although the "New SI" should provide a better definitions of the base quantities, it suffers the drawback that it becomes more difficult to introduce the concepts of unit definitions to students who are in their early teens. This has been partially remedied in version 9 of the SI brochure by including an enhanced section on the history of SI. Unfortunately this history only deals with the units concerned since they came under the care of the CGPM.
I feel that the historic section could be enlarged to explain what happened before the signing of the Treaty of the Metre. For example that the Celsius scale was originally based on the freezing and boiling points of water. This definition is something with which pre-teens and early teens can relate. Having a potted history to which teachers can refer will assist in teaching SI, especially at a stage when children are being introduced to science – knowing that a litre of water has a mass of about one kilogram is far more useful to most people than understanding the nature of the Planck constant. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of James Sent: 22 December 2014 17:53 To: U.S. Metric Association Subject: [USMA:54522] Roadmap to the new SI Dear friends, Barry Taylor (NIST) has just now sent me some very useful information on the roadmap to be followed in order to put the new SI in place at the 2018 CGPM meeting. Go to http://www.bipm.org/en/about-us/ and scroll down in the News column on the right hand side until you reach the item http://www.bipm.org/en/news/full-stories/si-roadmap.html Opening that produces a short brief including a link to a three-page Presentation: http://www.bipm.org/utils/common/pdf/SI-roadmap.pdf#page=3 The last slide shows a roadmap that details the tightly knit steps to be undertake to implement the new SI definitions. Following that, a new SI brochure will be produced. My guess is that the new brochure will come out in 2019. Happy Hanukkah and Merry Christmas to all. May our new year be a more peaceful one, at home and abroad. Jim Frysinger
