86 REPORT—1905. 
Colaba, Bombay.' 
Lat., 18° 53’ 45'’ N.; long., 72° 48’ 56’’ B.; alt., about 35 feet above sea-level. 
Foundation is on rock—a large boulder. 
Topographical Situation—The Observatory is located at almost the extremity of 
a narrow and somewhat rising strip of land called Colaba, about two and a half miles 
in length, running into the sea almost 8.8.W. from the island of Bombay. The 
breadth of the strip where the Observatory is situated is about 500 yards, about 200 
yards of which, near the eastern side, being occupied by the Observatory compound. 
The main Observatory buildings are located on the top of a small mound, sloping 
somewhat more abruptly on the east than on the west. The mean level of the 
ground on which all observation buildings are located is about 32 feet above mean 
sea-level. 
Geological Featwres.—The rocks generally in the vicinity and of the neighbouring 
hills, such as the Malabar and Cumballa Hills, are basaltic traps and are highly mag- 
netic. The probable dip of the trap is about 5° to the westward. Excavations show 
here and there large boulders of basalts lying in thick and hard beds of red and 
somewhat sandy soil. At several places where the rock crops out through the soil 
the depth of basalts appears to be very great, continuous rock being met to a con- 
siderable depth, as shown by the sides of an existing deep well in the compound. 
Water is always available at a depth of about 30 feet below ground. The 
nearest hill is Malabar Hill, about four miles north, across the Back Bay, while the 
highest hill, the Karauja Hill, about eight miles across the harbour towards E.S.E., 
subtends an angle of about 1° as seen from the Observatory. 
This is an astronomical observatory. 
N. A. F. Moos, Director, 
Caleutta (Alipore Observatory), India.? 
Cape of Good Hope, Royal Observatory. 
Lat., 33° 56’ 3'6 ; long., 1h. 13m. 54.76s. E. ; alt., 33 feet. 
Foundation is on the partly weathered rock of the Malmesbury beds—a quartzose 
slate—with good unweathered rock at from 16 to 30 feet below. 
Topographical, Situation.-—In a cellar of the main Observatory building, which is 
situated on a rising ground on the comparatively level country between Table Bay 
and False Bay. ~ 
Geological Structure.—‘ The site is underlain by the oldest rocks of this part of 
South Africa, the slates and quartzites known as the Malmesbury beds. These 
rocks form the whole 8.W. corner of the Cape Colony, and extend over many 
hundred square miles of country. No fossils have been discovered in any of the out- 
crops, but there is no. doubt that the old slates and quartzites were deposited at some 
period long anterior to the Devonian rocks of Europe. The Bokkevelt beds of Cape 
Colony contain Devonian fossils. Between these beds and the tilted Malmesbury 
slates there are 4,000 to 5,000 feet of Table Mountain sandstone, which is itself 
separated by a very marked unconformity from the old slate series. The Malmes- 
bury beds in petrological character resemble some of the Silurian slates and grits 
of the southern uplands of Scotland. ‘“ Cleaved quartzite” is the most accurate 
description. —Dr. Corstorphine’s Report. 
DAVID GILL, H.M. Astronomer. 
Carisbrooke (Newport, Isle of Wight), England. 
Observations at this ‘station thave been discontinued. Its situation is described 
in the ‘ British Association Reports ’ for 1896, p. 185. 
1 See Brit. Assoc. Rep., 1899, p. 176. 2 Tbid., 1899, p. 177. 
