A thorough report of the earthquake in Assam, in 1897, the most violent
and extended earthquake of historic times, has been made by Mr. R.
D. Oldham. From an abstract by Prof. Davis of Harvard University, it
appears that an area of 150,000 square miles was laid in ruins, all
means of communication interrupted, the hills rent asunder and cast
down in the landslips, the plains fissured and riddled with vents from
which sand and water poured forth in astounding quantities, causing
floods in the rivers, etc. A surrounding area of 1,750,000 square
miles felt a shock of unusual energy. The earthquake wave traveled
at the rate of 120 miles a minute. The vertical displacement of the
ground near the center of disturbance was probably as much as fourteen
inches--an unprecedented quantity; the vertical movement of earthquakes
of great violence, like the Charleston earthquake, is seldom more than
two inches.
Some of the results of this great earthquake of June 12, 1897, are
astonishing. Faults were produced, one having a throw of 25 feet and
a length of 12 miles; another a throw of 10 feet and a length of 2½
miles. The larger of the two dammed a river so as to form a lake
several miles in extent and ruining a forest of at least 50,000 trees.
Landslides of great magnitude were produced in the Himalayas and the
valleys of streams were changed beyond recognition.