Timelines under continual development by design.
Helpful maps for those who study the development of mathematics and science.
Chronologies Developed Here:
Statistical Mechanics
and Thermodynamics
Hypercomplex Numbers Electromagnetic Theory
Chronologies From Elsewhere:
List of Centuries The timelines of the ever-expanding Wikipedia
HistoryOfScience.com History of Science, Medicine, and Technology
Timeline Index Many timeline cross-sections of history. Lots of interesting timelines from way way back to the present.
Maps of War History maps and timelines of religion, conquest, governments, etc.
A Timeline of Symmetry in Physics, Chemistry, and Mathematics A very well-researched timeline that I very much recommend. Also contains links to biographies as I have done in my timelines. Great to see such resources.
A Timeline of Mathematics and Theoretical Physics Names and accomplishments in math and theoretical physics in the 20th century.
wikiTimeline A interesting general time-lining project.
Timeline of Romani History
History Topics in Mathematics Historical chronologies of many areas of mathematics. Great stuff!
HyperHistory Online A hypertext version of their famous wall-chart of history. Filled with lots of facts and a great resource, but a bit hard to find a specific history.
Chronology of Magnetospheric Exploration List of major events from 1600 to present, mostly in the 20th century, of course.
A Timeline of Electricity and Magnetism As the author says, "Mostly from E. T. Whittaker's 'A History of the Theories of Aether and Electricity'" going from 900 b.c. to 1905 a.d.
Physics Time-Line Lots of dates listed, but the quality is lacking in parts. Difficult to sort things out.
The History of Mathematics Seems like a good site, with lots of math info.
Timeline of Microcomputers Fun romp through the history of microcomputers.