DRIFT-SANDS AND THEIR FORMATIONS. 541 



liave disappeared, and ships will find free sailing-ground where 

 men are now living and cattle and sheep are pasturing. 



Of course, man struggles to defend himself against this enemy. 

 The only way of counteracting its movements is to cover the sand 

 with vegetation and make it inaccessible to the attacks of the 

 wind, and this is not very easily accomplished. The sand consists 

 chiefly — seventy-five to ninety-eight per cent — of uncultivable 

 quartz sand, in which only easily satisfied plants can be made to 

 grow. The wind is, besides, sometimes so strong on the sea-coast 

 as to permit lowly plants to grow only with difficulty, and trees 

 not at all. Sand is, moreover, so fugitive a substance that plants 

 are liable to be torn from it before they have taken firm root. But 

 these hindrances can be overcome, though with difficulty. One of 

 the first instances in which a sand mass was thus tamed was in 

 Denmark in 1738. The sands of the Landes in France have been 

 bound with entire success. Measures of precaution were under- 

 taken in the neighborhood of Dantzic about the middle of the last 

 century. As everywhere else on the Baltic, the dunes had been 

 covered by Nature, except on the side toward the sea, with firs and 

 bushes of all sorts, and thereby protected against the wind. But 

 the ignorant greed of men had removed the wood, grubbed up the 

 stumps, allowed cattle to tread the heaths at will, and treated the 

 dunes so recklessly that their protective covering disappeared, and 

 their sand masses were exposed to the winds. Consequently, at 

 the beginning of the eighteenth century the villages of Klein- 

 vogler and Schmergrube were wholly and Polski partly over- 

 whelmed. It was not till about the middle of the century, when 

 the dunes nearer to Dantzic began to encroach upon the fir-wood 

 appertaining to the city, that measures of protection were thought 

 of. The first measure suggested was the planting of fences of 

 fir-boughs on the comb of the dune, to intercept the sand brought 

 by the wind. This scheme failed. The deposits of sand in front 

 and rear of the hedges made the constant planting of new barriers 

 over the old ones necessary ; and the dune increased in height at 

 an alarming rate, involving a great danger of the sudden breaking 

 down of the ridge, when the destruction effected by the sand 

 would be worse than if it had been let alone. 



In this dilemma, the Natural History Society of Dantzic, in 

 1768, offered a prize for the best answer to the question, " What 

 are the most effective and cheapest means of preventing the over- 

 flow of the lowlands with sand, and of stopping the further growth 

 of the dunes ? " Titius, Professor of Natural History in Witten- 

 berg, gained the prize, by an essay in which he indicated the res- 

 toration of the coast-woods as the only permanent remedy, and 

 the planting of a sand-grass {Arundo arenaria) as the measure 

 with which the immediate emergency might be met. His sug- 



