The 21-era spine, seven eras each for Communication, Industrial, and Textile and Apparel Design, with every movement laid across it and every object in the collection plotted as a dot. India above, the world below, on one time axis. The collection runs from a 600,000 year old handaxe to this year, so the axis is spaced by depth in time: one continuous logarithmic ruler, no break in it. Zoom with the wheel, drag to pan, or move the window on the strip underneath.
Drag to pan, scroll to zoom around the pointer, pinch on a touch screen.
The whole 600,000 years, always. The tinted window is what the timeline above is showing; drag it to move, drag either edge to widen or narrow.
How to read the axis. Position is set by how deep in the past a year sits, on a single logarithmic ruler of years before now. There is no split scale and no break line any more: zooming does what the old split was compensating for, so the handaxe at 600,000 years and a brick at 4,600 years are both readable without cutting the axis in two. The ruler bottoms out at the last 40 years, which share the far right of the fully zoomed out view; zoom in and they separate. Equal distances are still not equal amounts of time, so read the tick labels, which re-space themselves from millennia to single years as you go in.
How the lanes are decided. An object is in the India lane if its recorded place names India, an Indian state or city, the Indus Valley, Mohenjo-daro or Sindh. Everything else is in the world lane. That is a string match on one field, and it is a rough instrument: it puts Indus sites in the India lane although they are in present-day Pakistan, because the subcontinent is what the eras are about, and it puts an Assam textile held in New York in the India lane, because place records where an object is from and not where it now sleeps. Movements are laned by which research file they came from. Era bands sit behind both lanes, because every one of the 21 eras names an Indian anchor and forcing each into one lane would falsify the source.
What a date here is. Every object's position is a single integer derived from its human-readable period string, always the earliest year that string names. A range, a century and a living tradition all collapse to one point. The period text on the hover card is the real record; the dot is a convenience. Movement and era ends behave the same way, and where a source says "onward" or "present" the end is set to this year. Where several objects fall within a few pixels of each other they are drawn as one counted marker rather than a pile; click it to zoom into the group and to list it in the detail panel.