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Town (Town House) is 23-84- in., at the Royal Observatory 27-95. 

 and at JNewlands (Bishop's Court) 55-54, which is almost the 

 highest record for any low-level station in the Cape Colony, the 

 extraordinary nature oi these results is obvious, and it is not 

 surprising that the vegetation of our mountains is so different 

 from that of the hills." 



Dr. Marloth's experiments showed that the summer of the 

 plants growing within the area of the cloud belt was not dry, 

 but that their environment approximated more nearly to that 

 of a swamp, a permanent swamp in winter, due to rainfall, a 

 periodical swamp in summer, due to clouds; further, that these 

 conditions explained the presence of " a luxuriant and thickly 

 set vegetation on the upper parts of these mountains ; why shrubs, 

 6 to 8 ft. high, crown the summit of Devil's Peak; why thickets 

 of beautiful heaths, 4 to 5 ft. high, grow on the top of Jonkers- 

 hoek peaks; why there is a little forest of yellow wood, Kigge- 

 laria, Olinia, and other trees on the top of Klapmuts Hill; why 

 the cedar grows only at a certain level on the Cedarbergen, why 

 Proteas and heaths abound on the Zwartebergen, and why there 

 are little lakes, even late in summer, on the top of Table Moun- 

 tain as well as close to the summit of Dutoit's Peak." 



Objections to Dr. Marloth's rough-and-ready methods of 

 investigation were at pnce raised by Mr. Charles Stewart,* 

 which were, perhaps, justified from a meteorological standpoint; 

 but as Sr. Marloth stated in his reply, t after two years' further 

 experiments, he did not look upon the figures as being equiva- 

 lent to records of rainfall, for during rain a great deal of water 

 runs off the" bare rocks and reaches the streams immediately, 

 whilst water condensed from the clouds is captured only where 

 sufficient vegetation exists, which, on the other hand, retains 

 a large proportion of it in the spongy root system. He stated 

 further that there could be no question that the vegetation of the 

 South African mountains was a very important factor in the 

 regulation of the water supply of the springs and streams, and 

 that this influence was exerted in .two ways, firstly, by capturing 

 a not inconsiderable amount of moisture from the south-east 

 clouds, which would escape if the mountains were formed by 

 bare rocks only; and secondly, by protecting the water which 

 has accumulated in the soil and the rocks against the sun and 

 consequent evaporation . 



'there seems to be no doubt, then, that vegetation plays a 

 very important part in the collection and retention of moisture 

 under certain conditions, and the laurel forest of the Canaries 

 probably performs tins function in ju^t such a manner as do the 

 trees in the South African mountains. I have quoted Dr. Marloth 

 at considerable length, because, as he says, his earlier experiments 

 were apparently the first of their kind for determining the influ- 

 ence of mountain vegetation on the collection and retention of 

 moisture from passing clouds; and further, to bring to the 

 notice of the inhabitants of the Canary Islands how vital it may 

 be for them not only to preserve, but, if possible, to augment 



* S. Afr. Phil. Trans, l.c 

 f I.e. xvi. 103. 



