196 REPORT— 1897. 



Patras — Corinth. — September 9, 1888 ; August 25, 1889* (two inter- 

 ruptions). 



The earth-movements which were observed were as follows : — 



March 28, 1889. At 7'.S5h. at Wilhelmshaven, fairly large. 



September 13, 1889. At 6-50h. at Potsdam and from 7h. to 9-5h. at Wilhelms- 

 haven. 



February 9, 1893. At Strassburg 6-23h. to 8-48h., and at Nicolaiew 619h. to 8-07h.^ 

 heavy movement. The epicentre possibly near Samotrace. Two other earthquakes 

 were noted on this day. 



August 25, 1889. At Potsdam at 7-62h. and at Wilhelmshaven from 7-53h. to Oh., 

 a large disturbance. Epicentre near Patras. 



The Lipari — Milazzo fractures took place in depths of from 400 to 650 

 fathoms 2 or 3 miles distant from Vulcano, about north-east from 

 Solfatore. 



The Zante — Canea interruption occurred about 5 miles west by south 

 off Sapienza Island, in a depth of 1,500 fathoms with a clay bottom. 

 Soundings varied as much as 250 fathoms in the length of the ship, and 

 from 1,350 to 1,834 fathoms in half a mile. 



The first of the Patras — Corinth breaks occurred about 2 miles north 

 of Akraia, in mud at a depth of 197 fathoms, whilst one of the second 

 interruptions took place in the same locality, in depths varying between 

 408 and 270 fathoms within a mile, and the other, in cable No. 2, within 

 half a mile south of Morno point. 



Mr. W. G. Forster, writing in the ' Transactions of the Seismological 

 Society,' vol. xv., respecting these districts, tells us that after the Filiatra 

 shock in 1886 it was found, by the broken cable 30 miles away, that 

 some four knots of the same had been covered by a landslip, whilst the 

 depth of the water had increased from 700 to 900 fathoms. In 1867, 

 after the destruction of Cephalonia, the soundings taken after the shock 

 were different from those taken before. Again, on September 9, 1888, at. 

 5.4 P.M., the town of Vostizza, in the Gulf of Corinth, was destroyed, and 

 simultaneously the cable between Zante, Patras and Corinth was inter- 

 rupted. The cause of this, as deduced from soundings and the appear- 

 ance of the fractured cable, appears to have been either a sudden tautening 

 caused by the sweeping down of a mass of clay from a 100-fathom bank 

 to a 300-fathom bank, or the actual yielding of the bed on which the 

 cable lay. 



In 1889 a second cable was laid down in the Gulf of Corinth, but this, 

 when it had been down about three months, was, together with the 1884 

 cable, fractured at the time of an earthquake on August 25 at 8.51 p.m. 

 The 1889 cable seemed to have been smashed by the movement of a mass 

 of material about a mile in length, whilst the 1884 cable was broken at 

 two points by a slip on a 10 to 450 fathom bottom. 



In the districts considered by Mr. Forster, there are, as he points out, 

 great irregularities in submarine contours, the depths within short 

 distances changing from 50 to 300 and then to 1,000 fathoms. By the 

 deposition of silt, and the undermining of steep slopes by bottom currents, 

 the exit of underground springs and even rivers, overhanging shelves, 

 tottering and precipitous rocks, and other unstable arrangements, may 

 suddenly give way and cables suffer rupture. 



The facts are that the sub- oceanic contours are such that they might 

 be expected to be unstable, and that these contours, at the time of earth- 

 quakes, have suddenly been changed. In one instance there has been an 



