14 
that this is sage and wholesome advice, and the only question is, who 
is to sustain the expense? Not long ago, sonewhere- about the time 
that Dr Brown was prosecuting his labours, it will be remembered that 
General Wynard said that ‘‘ Nature had furnished the cups if only 
science would take the trouble to make them secure.” It is but to 
repeat an oft-told story that with a good supply of water South Africa 
would be une of the finest of nature’s gardens, and would be capable of 
producing two crops a year, in addition to furaishing fodder for sheep 
and cattle. The question of the water supply for irrigation and other 
purposes has been staved off year after year, and nothing has been done. 
It is not too much to say, however, that the question must make itself 
felt, as it is one of the chief factors in the ultimate prosperity of South 
Africa, The author is evidently ia love with his subject, and has con- 
tributed a mass of facts to Hydrology which will be useful to all coun- 
tries of an arid character.’ 
XI.—Forests and Moisture; or Effects of Forests on 
Humidity of Climate. Price 10s. 
In this are given details of phenomena of vegetation on 
which the meteorological effects of forests affecting the 
humidity of climate depend—of the effects of forests on 
the humidity of the atmosphere, and on the humidity of the 
ground, on marshes, on the moisture of a wide expanse of 
country, on the local rainfall, and on rivers—and of the 
correspondence between the distribution of the rainfall and 
of forests—the measure of correspondence between the 
distribution of the rainfall and that of forests—the distri- 
bution of the rainfall dependent on geographical position, 
or determined by the contour of a country—the distribution 
of forests affected by the distribution of the rainfall—and 
the local effects of forests on the distribution of the rain- 
fall within the forest district. 
Extracts From Prerace.—‘ This volume is one of a teries. In the 
first of the series—a volume entitled—published last year, Hydrology 
of South Africa ; or, Details of the Former Hydrographic Condition of 
the Cape of Good Hope and of Causes of its recent Aridity, with Sugges- 
tions of appropriate Remedies for this Aridity. 
‘This volume, on the effects of forests on the humidity of the atmos- 
phere and the ground, follows supplying illustrations of the reasonable- 
ness of the suggestion made in regard to the conservation and extension 
of forests as 2 subordinate means of arresting and counteracting the 
deseccation and aridity of the country.’ 
