People wanted to know whether the earthquake was preceded by the usual portents, or whether such signs had now to give way to the tracings of seismographs.
In spite of seismographs and explosions underground, every oil company spends at least £1 million on average on each drill that is sunk.
As sure as night follows day, the walking drag lines will follow the seismographs.
Inspections and spot checks on the evidence of external seismographs is quite insufficient for the control of nuclear test explosions.
I do not believe that it is necessary for us always to act as a seismograph, merely registering passively outside opinions.
This can be done within seconds to accuracies of 1 kilometer in regions where dense seismograph networks exist with inter-station distances of about 10 km.
With inexpensive seismometer designs and internet access, amateurs and small institutions have even formed a public seismograph network.
The air burst's blast wave, when it hit the ground, produced a seismic wave which registered on seismographs at magnitude 2.7.
