TIMBER. In the article Forestry and in the description of the more important species of useful trees, we have noticed those species gen erally cultivated for profit or ornament. Upon the importance of the timber resources of the country and the yearly increasing scarcity, and the need of planting for continued supply, we append a statement from an address, in 1871, by the editor, before the Illinois State Horticultural Society, and which is of as great force now as then in view of the continually diminishing supply, and also from the facts gathered in rela tion to forestry: It was remarked by Humboldt that, in felling trees which cover the crowns and slopes of mountains, man in all climates seems to be bringing on future generations too calamities at once—a want of fuel and a scarcity of water. The destruction of timber and the dense mass of natural grasses with which the prairies were originally covered, has added an other most serious one—meteorological disturb ances which are constantly modifying the climate, and if persisted in without compensa tion, must ultimately result in depopulating the country by rendering it unfit for human habita tion. It was asserted twenty years ago [now thirty—Editor] that, before the United Stales reached a pokulation of 50,000,000 that, through the waste of valuable timber, the folly and short-sightedness of the age would meet with a degree of censure and reproach not pleasant to contemplate. This point was reached before the census marked 40,000,000; and it is due principally to the causes just mentioned; which may be illustrated by the following deductions based upon facts: Heated air saturated with water in the form of vapor, gives up a portion of it if cooled, or absorbs more if its heat is in creased. This power is doubled with each in crease of temperature of twenty-seven degrees of Fahrenheit; therefore, if a warm current meets a colder one, both saturated, a portion is con densed and forms clouds and rain. If in falling this rain passes into a dry current of air, it may be absorbed partially or wholly before reaching the earth; or, falling through a saturated atmosphere, from high elevations or cold strata, its intensity may be ihcreased by aggregation. All open countries are subject to violent atmos pheric -alternations; but if clothed with vegeta tion, especially timber, the changes are less violent, and.the temperature is equalized. The solar rays have more power to heat plowed soils, than those unplowed; and just in propor tion to their powers of absorption, will be their pobver to give up this heat again. - In the cool
recesses of the forest, evaporation goes on more slowly than in the open plain, for the reason that the rays of the sun seldom reach the earth, and hence their power of holding moisture and giving it out slowly by percolation to feed the springs that always abound in such regions. This cooler atmosphere, condensing moisture from the currents of heated and saturated air flowing in from the more open country, often causes the gentle rains incident to such locali ties. Evaporation causes latent heat, precipita tion sets it free again or renders it sensible; and, thus nature by increasing the capacity of air to both hold and give up heat and moisture pre vents those deluges that would otherwise occur, stores up heat and moisture to be given out regularly and slowly, unless influenced by violent meteorological convulsions. These are of infrequent occurrence in timbered districts, but are frequent, and often devastating, in open countries. While timbered regions have equal and gentle rainfalls, the open country beyond is visited with rain at unequal intervals, and torn by terrible winds accompanied by violent electrical phenomena. Forests modify all this, and although they may have no marked effect upon the amount of annual rainfall, they do cause it to be more equally and gently dis tributed, than is the case in countries where there is but little timber. Wide regions entirely destitute of timber have little or no rain, and become deserts often, not from their want of fertilizing inorganic and organic elements, but for want of that great fertilizer, water. I am well aware that Professor Henry is reported as saying' that the records of the Smithsonian Institute do not indicate an annual diminution of during the_last twenty years. An nual granted, hut its irregularity and also its infrequency is becoming more and more notice able each year, and is apparent to the most ordi nary observer; and it is this irregularity that is constantly harassing the farmer and horticultu rist, more and more with each successive year. The meteorological changes incident to the de struction of forests seem to be well known to the ancients, and hence the many mythological tales that have come down to us through the old Hin doo, Chinese, and other writings. Alluding thereto, the poet Bryant says: The groves were God's first Temples.