482 EEPORT — 1881. 



instruments in use are little better than ptilosophical toys, and that, in 

 general, they afford no direct, comparable, or reliable indications of either 

 velocities or pressures ; and that they are often so injudiciously placed as 

 in some instances to i-ecord the effects of combined and, therefore, locally 

 accelerated currents ; whilst in other instances, they record only the 

 effects of obstructed and, therefore, locally retarded currents. 



As the acquisition of accurate data is of great and increasing- 

 importance, the author suggests that the British Association, and other 

 learned societies interested in physical investigations, should unite in 

 providing the necessary funds and observers for the purpose. 



On the Island of Socotra. By Bayley Balfour, Sc.D., M.B., Regius 

 Professor of Botany, University of Olasgoiv. 



[A communication ordered by the General Committee to be printed in extenso 



among the reports.] 



The island of Socotra lies off the N.E. corner of Africa in lat. 12° 

 19' to 12° 42', and long. 53^ 20' to 54° 30'. Its extreme length from 

 east to west is about 72 mdes, and its breadth about 22 miles. 



From Cape Guardafui 140 miles, it is a little more distant from the 

 Arabian Coast (about 500 miles from Aden), and still further away from 

 the Indian Peninsula. 



It is the most easterly elevation of land on a coral bank lying to the 

 N.E. of Africa, upon which, between it and Cape Guardafui, other islands 

 (Abd-al-Kuri, Kal Farun, Samheh and Darzi — known commonly as The 

 Brothers, and Saboynea) of smaller size occur. On no part of this bank 

 is the depth of water over 200 fathoms, but between it and the African 

 coast is a channel reaching 500 fathoms. Around Socotra is a narrow 

 coral reef. 



Perhaps no island of like extent, and lying, as one may say, on the 

 threshold of civilisation, has remained in later times so generally unknown 

 as Socotra. Situated on the highway of traffic to the East by way of 

 Suez and the Red Sea, it is almost invariably sighted by steamers making 

 for or from the Gulf of Aden, and thus to those who have passed along 

 this route, its locality, or at least its name, will be known. To the scien- 

 tific world it has been familiar as the country of a kind of aloes, the 

 designation of which as Socotrine, has by some been traced to the name of 

 the island. But to the majority of people its existence and its name are 

 alike unknown, or at most it is associated in a vague sort of way with the 

 East Indies. 



The causes for this are not difiBcult to discover. The extreme outlying 

 land in this region of the Indian Ocean, the island is exposed to the full 

 blast of the monsoons, however they blow, and possessing no hai'bour in 

 which a ship can at all times ride safely at anchor, it offers no induce- 

 ments to ships seeking shelter. Then the currents which sweep past its 

 shores run with considerable force into the Gulf of Aden, and there have 

 been several shipwrecks on it, as well as on the African coast adjacent — 

 the high hills of the island being easily mistaken for the mainland, and vice 

 versa — and navigation in its vicinity is altogether somewhat hazardous. 

 It is not surprising, therefore, that passing vessels avoid the island as 



