sentence2_structure: Seismologists<>measured<>the intensity of an earthquake with the mercalli scale<>originally
sentence1: Greek seismologists, however, have disputed the intensity of yesterday's tremor, claiming it registered 6.8 and not 5.8 on the Richter scale as Turkish seismologists reported, while experts in Strasbourg say the quake measured 6.1.
sentence2: Seismologists originally measured the intensity of an earthquake with the mercalli scale.
question: How did seismologists originally measure the intensity of an earthquake?