Hogbeiw — East Coast Earthquakes, 191^-/7. 



281 



8th August, 1904. A day later (6th— 7th August, 1917) a sharp shock, 

 though not so severe, was felt in the region from Gisborne to the East 

 Cape, evidently from the east or east-south-east. It is quite possible that 

 the latter was from the north-east end of a fault-line of which F marks 

 the south-west end. F is about 185 miles from Wellington, and 285 miles 

 from Christehurch. 



Earthquake origins east of New Zealand. 



The times relied upon for the determination of F were those of the first phase 

 ("preliminary tremors") at Apia, Samoa, 15h. 56m. 27s. (Wiechert) ; Riverview, 

 Sydney, 15h. 55 m. lis. (Wiechert); Christehurch, N.Z., 15 h. 51m. 24 s. (Milne); 

 Wellington, N.Z., 15h. 51 m. 6 s. These, with a velocity of propagation of 9 - 17km. 

 sec, show the time at the origin to have been loh. 50m. 34s., G.M.C.T., 5th August, 

 1917 (3h. 20 m. 34 s., N.Z.M.T., 6th August). The respective distances of the four 

 places named from F are : Apia, 3,235 km. (chord) ; Riverview, 2,538 km. (chord) ; 

 Christehurch, 456 km. ; Wellington, 296 km. 



The times and other observations forwarded from New Zealand telegraph -offices, 

 while less exact, afforded a general confirmation of the residt obtained from the instru- 

 mental observations. 



