Wind can be defined as, air in motion relative to the earth. It is usually described by giving its speed, and the direction or region from which it moves. Thus a north wind is one that blows from the north. The speed can be given by a suitable units such as mile per hour.

      Generally in our material life the winds play a very great role to the benefit of man. It sometimes might be of important loss too.

      The wind cools and purifies the air. It fertilizes the soil and pollinates the trees. Winds propel our ships and air-buses, making our international connections and communications. It helps rainings, that we know it the Mercy of God.

      Winds have a high rank among the important forces that shape the surface of the earth. They wear away rock materials and soil, and transport the materials over vast areas, and deposit them upon the earth.

      Wind has also a sand blasting effect. The sands that it carries through the air scratch and scrap whatever of surfaces they strike. If automobiles are driven in the sand storms, their paint may be worn off. The sand blasting effect of wind upon the rocks for a longer period of time is much greater. The effect is sometimes confined to scattered blocks and pebbles.

      Sometimes it happens so that many tons of dusts are removed by the wind from a given region, the consequences of which is unpredictable.

      Winds may influence the distribution of plants, for they affect the nature of soil. For example, high winds that cause shifting of the soil, will prevent the growth of many plants with shallow root system.

      In order that fertilization may take place the pollen grains have to be born from the anther to the stigma of the pistil. This transfer is called pollination which is sometimes done by the wind. The flowers of corn, wheat, oaks, elms, chestnuts, and many other plants are pollinated by the wind.

TRANSLATOR'S NOTE