About Daylight Saving Time - Benjamin Franklin is credited with being first to suggest the idea of daylight saving while living in Paris 1784. The arguments for and against, and story of its erratic adoption until the introduction of the Uniform Time Act by President Lyndon Johnson in 1966, are documented in this site from the US Department of Transportation. Want to find DST dates up to the year 2099? You can do it here. Or, if you need to know precise details of changeover dates and times in more than 70 countries that observe DST, this is the place to find them. There is extraordinary variation, even within a single country, particularly if it is spread over several time zones. Far from being a simple case of 'spring ahead - fall back', the choice of when to change the clocks is often an arbitrary decision. Though this may be of little importance to most of us, imagine what a nightmare it must be for airline schedulers, or even the late night bar manager trying to work out the staff roster. I confess there is more detail here than I would ever need or want to know, but I'm sure there's someone out there who will enjoy looking up when DST starts and ends in Namibia. (11 December 2001) JAS
http://webexhibits.org/daylightsaving/
Fermi Questions Library - If you don't know what a Fermi question is, and how to answer one, then you'll do no good at the village fete guessing the weight of the giant cupcake or the number of coins in the penny jar. There is no archetypal Fermi question but such questions as: 'How many piano tuners are there in New York City?' and 'How many jelly beans fill a one-litre jar?' are the kind of examples this site uses to illustrate their power. The answers one gets will usually provide an order of magnitude range within which the 'true' answer will lie. For instance, the site takes us through the former question, step by step - how many people in NYC, how many have a piano, how often do they have it tuned, how much work can a single piano tuner do? Etc etc. Their answer is 500. One might assume that there could be many more or far fewer, but certainly no more than 5000 and no less than 50. Of course, the serious application of Fermi questions is not to win prizes at village fetes or help tickle the ivories, but to help students understand how to estimate properties that are generally impossible to count precisely. A good starting point for using up all those spare envelope backs! (15 August 2001) DB
http://mathforum.org/workshops/sum96/interdis...
Philosophy of Time - What is time? If you've ever wondered, this entry from the Internet Encyclopedia of Philosophy has plenty to say on the subject. It covers the early musings about time from philosophers such as Aristotle and Zeno of Elea (who argued in his paradoxes of motion that the fast-running Achilles could not catch up with a tortoise), before discussing topics such as Time's Arrow (the temporal asymmetry of events such as milk being stirred into a cup of black coffee). There is a lot of material about the modern concept of spacetime in General Relativity, the Twin Paradox, and black holes. The text is well written, and surprisingly easy to follow, despite covering some very tricky concepts. It's great to browse through, and one can also delve into other philosophical topics in this online encyclopedia. (18 March 2001) DP-P
http://www.utm.edu/research/iep/t/time.htm
Calendars through the Ages - This site offers pretty much everything you could want to know about calendars, from the definition of a year, to the astronomical basis of the calendar to the history of the development of western calendars. You can find the answers to important questions such as just why poor February has only 28 days and whether the year always started on 1 January. There is also information on a variety of other calendars than the Gregorian, from those currently in use - such as the Chinese, Indian, Jewish, Islamic and Christian - to those no longer used - such as the Mayan, Roman and French Revolutionary. Also on offer are a history of the seven-day week and a timeline of interesting calendar facts. (17 February 2001) KN
http://www.webexhibits.org/calendars/
Measure 4 Measure - There are hundreds (if not thousands) of sites out there on the web that perform specific functions for the browser, including translation, conversion, calculation, estimation and so on. Measure 4 Measure is is a collection of some of these sorts of sites, with a brief description of each site. The Science/Mathematics sub-division includes sites that calculate everything from angular velocity to body surface area to the wind chill factor and everything inbetween. In Health, you can find sites to see how many calories you burn, find out your risk of getting breast cancer (if you're a bloke, you probably won't need that one) or check how your child's growth measures up to that of his or her peers. There are also a number of financial tools and a section called "A Measure of Everything Else" which really does cover everything else - from string tension for musical instruments to the right name for your baby to how much it will cost to renovate your bathroom. A great idea. (15 February 2001) KN
http://www.wolinskyweb.com/measure.htm
Manor House Museum - Tucked away in a corner of what is actually a very attractive Bury St. Edmund website is the Manor House Museum. .The Manor House Museum has two collections, one of art and the other of horology . In 1953, Fredrick Gersham Parkington donate his extensive watch collection to the borough, where it became the basis of the Manor House collection. This has been added to steadily ever since, resulting in one of the finest time piece collections in the world. Part of this outstanding collection is introduced on line, running from portable sundials and Renaissance clocks up through the "John Bull" an English "dollar watch" that signals the demise of English horology. This site stands out is the exceptional quality of the time pieces shown, indeed, a quality rarely seen elsewhere. Perhaps the only complaint that can be made is that one wishes more pieces of this truly exceptional collection had been shown on line. (21 November 2000) WTS
http://www.stedmunds.co.uk/manor_house.html
The Quartz Watch - In 1927, Warren Morrison, a Canadian engineer working for Bell Laboratories in the USA invented the quartz clock and revolutionized the way time was kept. By the early 1970's microelectronics had put quartz watches on everyone's wrists, and in a few short years, almost entirely swept away the mechanical watch, a technology with over 500 years of development. This excellent site covers in depth both the inventors behind the quartz watch , the "watch wars" as various countries battled for dominance in the quartz market and the development of the technology from Pierre Currie's discovery of piezoelectricity in 1880 through the development of the Timex Indiglo in 1991. A must read site for all horological buffs and anyone with even the slightest interest in timekeeping. (5 November 2000) WTS
http://www.si.edu/lemelson/Quartz/
