Here is a recent radio story about the "NetQuakes" program, in which private citizens in California volunteer to bolt a shoebox-sized seismograph onto the floor of their home or garage, which will measure and record earthquake data and send it over the web to the US Geological Survey (USGS).

By deploying numerous such devices throughout California, the USGS hopes to gain a better picture of the full range of ground motions. By using the homes of private citizens, the agency can deploy more sensors and deploy them in places that it otherwise could not, especially dense urban areas (such as San Francisco -- the link above shows that the USGS is still looking for more volunteers in northern California).

Interestingly, the accomplished astronomer and mathematician Zhang Heng (thought to have lived from AD 78 - AD 139 during China's Han Dynasty) came up with a similar idea almost two thousand years ago (minus the internet component). His brilliant device is pictured above, and it consisted of a huge bronze urn, almost eleven feet high, featuring eight evenly-spaced dragons clinging to the sides in the four cardinal directions and the four ordinal or intercardinal directions.

As explained on this page from Wellington's Te Papa Museum (in Wellington, New Zealand), which has a display of a half-sized replica of a Zhang Heng device, the urn was fixed to a chassis to prevent it from tumbling. "When waves from an earthquake move the ground, the vase and chassis shake in the same direction as the passage of the waves. Inside the vase there is a heavy upside-down pendulum swinging on a fulcrum low in the vase. This sways in the direction of the movement of the vase, but inertia means that its movement is set off more slowly than that of the vase itself."

The motion of the pendulum caused by the earthquake wave thus strikes the inside of the vase on the side corresponding to the direction from which the earthquake wave arrived. Each dragon has a corresponding mechanism arm on the inside of the vase, which if struck by the pendulum causes the jaws of the dragon to open, releasing a brass ball inside the dragon's mouth. The ball then falls into the open mouth of one of the eight bronze toads positioned on the floor beneath each dragon.

The Te Papa Museum explains: "It is fascinating to speculate that a number of these instruments, set up in various places, could have made an earthquake-recording network for identifying the epicentres of earthquakes, similar to today’s seismographs." In other words, the ancient Chinese may have set up a NetQuakes program of their own.

The museum page further explains that "The Chinese have a very long-standing tradition of the scientific study of earthquakes – both locating and predicting them." This is very interesting in that the Chinese culture also has a long-standing tradition of astronomical study and incorporation of the significance of the celestial motions into their cosmology. Significantly, the inventor of the ingenious seismograph shown above was an astronomer.

This juxtaposition may be a clue that the origin of earthquakes and the origin of the celestial phenomena discussed in other pages of this blog are in fact connected, which is exactly what is argued by the hydroplate theory of Dr. Walt Brown and explored at length in the Mathisen Corollary.

If I lived in a part of California where they were looking for volunteers for the NetQuakes program, I would certainly sign up. However, I think I would insist they equip my home with one of the dragon seismometers of Zhang Heng rather than the small blue shoebox-sized sensor units described in the radio story.