I just found a remarkable YouTube video clip.

Someone spliced together, side by side, two reels of film. One features a journey along Market Street, San Francisco, just four days before the devastating 1906 earthquake, the other features the same journey along the same street after the earthquake and the subsequent devastating city-wide fire.

[youtube]http://www.youtube.com/watch?v=6TaxcXfSwdE[/youtube]

For those unfamiliar with the details, the journey runs along Market Street, running from south-east to north-west. At the end of the journey, a tower looms in the distance - this is the central tower of the San Francisco Ferry Terminal, which, amazingly, not only survived the 1906 earthquake, but the 1989 earthquake too. It's possible to compare the above video footage with this massive still photo of the 1906 earthquake aftermath, which, if you line up with the ferry tower, looks along Market Street in the opposite direction. Out of interest, that still photo was taken by attaching a camera to a kite, flying it to a height of 2,000 feet above the city, firing the shutter, then reeling in the kite!

It's instructive to view that large still photo and see just how much of San Francisco was wiped out in the 1906 earthquake and fire. It looks as if someone dropped an atomic bomb on the city. Then, go back to the video footage, and watch in full again, and take note of the buildings in each of the side-by-side clips ... it's possible to identify which ones were destroyed with some precision by back and forth comparison.

The fact that these two reels of movie film were shot within days of each other, either side of one of the biggest disasters to strike America, is quaintly serendipitous.

Wow.