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ner their humid atmosphere and their feathered singers effectually obstruct the march of 

 armies of locusts in the Orient, or hinder the progress of vast masses of acrydia in North 

 America, or oppose the wanderings of other insects elsewhere, all this has been clearly 

 witnessed in our own age. How the forests, as slow conductors of heat, lessen tlie tempera- 

 ture of warm climes, or banish siroccos ; how forests, as ready conductors of electricity, much 

 influence and attract the current of the vapours, or impede the elastic flow of the air with its 

 storms and its humidity far above the actual height of the trees, and how they condense the 

 moisture of the clouds by lowering the temperature of the atmosphere, has over and over 

 again been ascertained by many a thoughtful observer. In what mode forests shelter the 

 soil from solar heat, and produce coolness through radiation from the endlessly multiplied 

 surfaces of their leaves, and through the process of exhalation ; how, in the spongy stratum 

 of decaying vegetable remnants, they retain far more humidity than even cultivated soil ; 

 how they with avidity re-absorb the surplus of moisture from the air, and refresh by a never- 

 wanting dew all vegetation within them and in their vicinity, has been explained, not only 

 by natural philosophy, but also often by observations of the plainest kind. How forest 

 trees, by the powerful penetration of their roots, decompose the rooks, and force unceasingly 

 from deep strata the mineral elements of vegetable nutrition to the surface ; how they create 

 and maintain the sources for the gentle flow of watercourses for motive power, aqueducts, 

 irrigation, water traffic and navigation ; how they mitigate or prevent malarious influences, 

 of all this we become cognisant by daily experiences almost everywhere around us. We 

 have to look, therefore, far beyond a mere temporary wood supply, when we wish to estimate 

 the blessings of forest-vegetation rightly ; and our mind has to grasp the complex of causes 

 and sequences originating with and depending on the forests, before their value as a total 

 can be understood." 



" Let us then take timely warning ; let us remember that denuded earth parts with its 

 warmth by radiation, and is intensely heated by insolation ; that thus in woodless countries 

 the extremes of climate are brought about in rendering the winter-cold far more intense and 

 boisterous, and the summer-heat far more burning and oppressive. Let us remember why the 

 absence or destruction of forests involves periodic floods and droughts, with all the great disasters 

 inseparable therefrom. Let us bear in mind that even in our praised Australia many a 

 pastoral tenant saw his herds and flocks perish, and even the very kangaroos off his run ; how 

 he looked hopefully for months and months at every promising cloud which drew up on the 

 horizon, only to dissolve rainless in the dry desert air ; while when the squatter's ruin was 

 completed, the last pasture parched, and the last waterpool dried up, great atmospheric 

 changes would send the rain-clouds over the thirsty land with all the vehemence of precipita- 

 tion, and would convert dry creeks into foaming torrents, or inundate with furious floods the 

 very pastures over which the carcases of the famished cattle and sheep were strewn about ! 

 Picture to yourselves the ruined occupant of the soil, hardly able to escape with his bare lite 

 from the sudden scenes of these tragic disasters ! Fortunately, as yet such extreme events 

 may not have happened commonly ; yet they did occur, and pronounced their lessons impres- 

 sively. Let it be well considered, that it is not alone the injudicious overstocking of many a 

 pasture, or the want of water storage, but frequently the very want of rain itself for years in 

 extensive woodless districts, which renders occupation of many of our inland tracts so precari- 

 ous. Let it also not be forgotten, how, without a due proportion of woodland, no country 

 can be great and prosperous ! Remember how whole mountain districts of Southern Europe 

 became, with the fall of the forests utterly depopulated ; how the gushes of wide currents 

 washed away all arable soil, while the bordering flat land became buried in debris ; how its 

 rivers became filled with sediment, while the population of the lowlands were at the same time 

 involved in poverty and ruin ! Let us recollect that in many places the remaining alpine in- 

 habitant had to toil with his very fuel for many miles up to the once wooded hills, where 

 barrenness and bleakness would perhaps no longer allow a tree to vegetate ! It should be 

 borne in mind that the productiveness of cereal fields is often increased at the rate of fully 50 

 per cent, merely by establishing plantations of shelter-trees ; that the progress of drift-sand is 

 checked by tree plantations ; and that a belt of timber not only affords protection against 

 storms, but also converts sandy wastes finally into arable meadows, thus adding almost un- 

 observed, yet unceasingly, so far to the resources of a country." 



" Shall we follow then the example of those improvident populations, who, by clearing of 

 forests, diminished most unduly the annual fall of rain, or prevented its retention ; who 

 caused a dearth of timber and fuel, by which not solely the operations of their artisans be- 

 came already hindered or even paralysed, but through which even many a flourishing country 

 tract was already converted almost into a desert. Should we not rather commence to convert 

 any desert tract into a smiling country, by thinking early and unselfishly of the requirements 

 of those who are to follow us ? Why not rather imitate the example set by an Egyptian 

 sovereign, who alone caused, during the earlier part of this century, 20,000,000 of trees to be 

 planted in formerly rainless parts of his dominions." 



