ON SEISMOLOGICAL INVESTIGATIONS. 91 
Trinidad, West Indies. 
Lat., 10° 40’ N.; long., 61° 30’ W.; alt., 66°71 feet above mean sea-level. 
Foundation ig on hard pan—sand'and clay—on a base of concrete 6 feet deep. 
Topographical Situation.—On tairly level ground at the foot of a ridge distant 
about 500 feet and 500 feet in height. “In the opposite direction, at a distance of 
about two miles, is the sea: : 
Geological Structure.—Yellowish sandy, slaty shale with quartz contortions. 
Time-heeping.—Daily astronomical observations are taken by Survey officer. 
J. H. Hart, Director. 
Victoria, British Columbia, Canada. 
Lat., 48° 23’ N.; long., 123° 19’ W.; alt., 12 feet. 
Foundation.— The instrument is placed upon a concrete pillar (about 18 inches 
square at top), which goes down 9 feet 6 inches toa bed of hard pan which overlies 
the native rock of the island. 
Topographical Situation—The station is in the basement of a large three- 
storey brick building, formerly used as a Custom House. The ground floor of this 
building is on the water-front street, from which there is a gradual slope down to 
a wharf; the basement is about 10 feet below the level of this street, and from the 
street the city gradually rises up a further incline of about 150 feet. 
The nearest hill is Mount Douglas, 696 feet altitude, distant between four and five 
miles to the north-eastward. 
To the westward, about 12 to 14 miles away across the water (sea) known as 
Royal Roads (tbe entrance to Esquimalt Harbour}, lies the range of mountains 
the Sooke Hills, running north-west and south-east, and reaching about 1,000 feet 
altitude. These hills are outlying parts of the great mountain ranges which form 
the backbone of Vancouver Island, with peaks reaching an altitude of 6,000 feet. 
Twenty miles to the southward, across the Straits of Juan de Fuca, is the 
northern coast of the State of Washington, and from the water's edge rise in suc- 
cessive tiers, running east and west, the splendid chain of mountains known as the 
Olympian Range, whose summits attain 8,000 feet of altitude. These summits are 
distant from Victoria from 60 to 75 miles.’ 
Geological Structure.—Dr. G. M. Dawson, the late Director of Geological Survey 
of Canada, says on page 88 of his Report, 1876-77 :— 
‘Volcanic action has played a large part in the building up of these rocks of 
Vancouver Island, and near Victoria probably nine-tenths of their entire thickness 
is made up of ashbeds, interleaved with lavas and other igneous rocks. These, from 
their composition, have yielded readily to metamorphism, and now lithologically 
resemble, as you have pointed ovt, the rocks of the Huronian and altered Quebec 
groups of Eastern Canada. This likeness, with the fact that the rocks still preserve 
not alone the chemical, but also in some places the mechanical, characteristics of 
volcanic rocks,’ &c. 
Mr. W. L. Sutton, a well-known resident geological expert, says that the Victoria 
rock is dense, igneous, and quite massive, with comparatively little jointage, and 
closely allied to diabase in general character. 
Time.—This is not an astronomical observatory, but our chronometer is rated at 
least once a week by comparison with the time which is given over the Canadian 
Pacific Railway telegraph, from the Montreal Astronomical Observatory ; our office 
telegraph being switched on to the local C.P.R. telegraph office and communication 
received direct from Montreal. 
E. BAyNzEs Rep, Superintendent. 
III. The Origins of Large Earthquakes wm 1904. 
The number of earthquakes recorded at Shide in 1904 was eighty: 
three. The localities from which twenty-eight of them originated are 
1 See Brit. Assoc, Rep., 1899, p. 172. 
