MOVING MOUNTAINS.

Thames Star, Volume LIX, Issue 16627, 24 October 1925, Page 8

MOVING MOUNTAINS.

There is a verse which says something about little drops of water and little grains -of sand making the mighty ocean the steadfast land. In ' spite of it, however, some of the land that is made up of grains of sand is anythings but steadfast. For many sandhills have a habit of moving. |

If you watch the dry sand on a beach during a strong wind you will see the grains of sand being driven before the wind. It is the winds that build up the sandhills at the back of the beaches, and when the sea breezes are strong and steady these sand- ' hills have a tendency to move inland- i This is particularly the case where the scrub or trees on the land at the back of the sandhills, which tended to act as a barrier, have been removed. It is said that this is the reason why j the sandhills a little to the north of Cronulla have spread inland till in places they have covered nearly the whole width of the neck of land between the ocean and Botany Bay. i

In most places along the coast the cases they grow to a great height. The Cronulla sandhills are nearly 100 ft high, and are a landmark visible for miles. At the end of the Seven-Mile Beach •at Pittwater (the Tasmanian, not the N.S.W. Pittwater) the huge sandhills have covered up big gum trees, some of them 70 or 80 feet high. Some of the trees are completely buried, while others are just keeping their heads above the sand.

At Marion Bay, not far from Pittwater, on the Tasmanian coast, re mains of a buried forest are uncovered from time to time amongst the sandhills. It consists mostly of honeysuckles (Banksias) and of oaks (Casuarinas). It is curious that there are no Casuarinas growing on that particular part of the coast. It is not on the coast only that the sand shifts. In the dry districts of the interior there are in places long sand ridges covered with pines. Where these have been cleared and cultivated the sand sometimes blows away in dry weather. Indeed, in times ot drought the sands and surface soil are blown about by the winds over large areas. A covering of vegetation tends to keep the sand together and prevents the wind from getting hold of it. The difficulty is to keep the sand still long enough to let the plants take a firm hold. Marram grass, which flourishes on sand and forms a kind of network on the surface, has done good service in staying the march oi sandhills.