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evaporation goes on in a very rapid manner. It is chiefly to these causes alone that I 

 attribute the fact of their being so few never-failing creeks and rivers in this colony. 

 Now, were there judiciously laid out plantations all over the country, and the trees con- 

 stituting these being at such distances apart, and of such kinds as would efiectually shade 

 the ground from the sun and prevent evaporation to a certain extent in these parts, or at 

 least in a much slower manner than is done at present, the rain would have time and op- 

 portunity to be absorbed into the ground, and by percolating to considerable depths, 

 come out again at a lower level, and thus cause streams of water where none exist at 

 present, and so on from place to place, keeping up a general degree of humidity to refresh 

 and encourage the growth of vegetation. 



3. " Forests have a Tendency to Equalize Rainfall : — In this colony, the climate of 

 which is considered very dry, nearly as much rain falls within the twelve months as 

 there falls within the same period in some countries which are nearly humid ones. In 

 moist climates we find that on nearly three-fourths of the days of the year, rain falls more 

 or less. In this country, again, there are at least three-fourths of the twelve months 

 which are entirely cloudless. And still the rainfall in both instances is not in like man- 

 ner disproportionate so far as the total amounts for the year are concerned. These 

 appear somewhat contradictory statements, but yet they are approximately correct for 

 many cases which could be cited. The reason of the difference is not that the one country 

 lies perhaps in the northern hemisphere, and the other in the southern, or that the one 

 may be fifteen degrees nearer the equator than the other. No ; the grand secret is that 

 the country which has its rainfall spread over the whole year is thickly covered with 

 trees, while in the case of our own colony there is a very small proportion of its area 

 occupied by forests. In two or three hours in this country as much rain will fall as 

 would occupy two days steady drizzling in Great Britain. 



4. "Forests Attract Rainclouds: — That this is the case is now a very well ascertained 

 fact. I do not, however, hold myself to the opinion of some writers that the trees them- 

 selves abstract the rain, but rather that the results flowing from a large body of trees have 

 this tendency. To put the matter in a scientific form we find (1) from the shade given 

 by the trees the temperature of the earth is lowered ; (2) the atmosphere hovering im- 

 mediately above the trees is in consequence lower than that in part of the country adjoin- 

 ing which may be clear of vegetation ; consequently it follows (3) that if hot clouds flow 

 over a plantation they will be cooled down and their moisture condensed upon coming in 

 contact with the cold, humid atmosphere hanging about the trees, and as their power of 

 holding water in a condition of vapour is sensibly diminished in a certain ratio according 

 to the fall of temperature, the result is a deposit on the ground of either rain, mist or 

 dew ; and again, (4) clouds containing vapour, which have blown over dry ground 

 heated by the sun, where the air is in consequence highly rarefied and warmer than the 

 clouds, these dissolve themselves and vanish ; but should these clouds come in contact 

 with the cooler air above masses of trees, they become overcharged with moisture, and 

 rain is the result. 



5. " Forests Subdue Aridity : — We have seen that the planting of large bodies of trees 

 has the indirect influence of attracting rainclouds to the sites occupied by them, and that 

 the atmosphere generally about woodlands is in a continual state of moisture by trans- 

 piration from the pores of the leaves, and by a certain amount of evaporation from the 

 ground by the heat of the sun. From this, then, it will at once be seen that by planting 

 arid tracts of land with properly proportioned belts of timber here and there through 

 them, the result is (1) lower temperature ; (2) arrest of hot winds ; (3) shelter ; (4) more 

 frequent rains ; and (5) a more humid climate generally, thus making such tracts of 

 country suitable for agricultural purposes. 



6. " Forests make Climate more Humid : — This is a result and contiguous part of the 

 whole system of the different influences of trees upon climate which have already been 

 explained. Water is sucked up from the soil by the roots of the trees, and is exhuded 

 again in the form of vapour from the stomates on the back of the leaves ; this rises into 

 the air and forms itself into clouds, and, if not deposited again on the ground as rain by 

 some counter-balancing atmospheric influence, is wafted across the country, cooling the 

 air and keeping up a supply of heavy dews which refresh and invigorate vegetable Ufe. 



