THE ECONOMIC ASPECTS OF SOIL EROSION 
335 
however, these abound. Perhaps the most noteworthy is that 
of the politically imjjortaiit island of Heligoland in the North 
sea, which is wasting with such rapidity that it is not likely to 
endure for more than two or three centuries to come. The east- 
ern and southern coasts of England, bordered as the}'’ are by soft 
stratified rocks, are also the seat of a rapid though locally varia- 
ble marine erosion, which within the limits of recorded history 
has sensibly diminished the areas of many parishes. Accurate 
data for determining the number of square miles thus lost to the 
service of man are lacking, but from a careful inspection of the 
English coast I am of the opinion that during the Christian era 
the total loss of area in that portion of the most important island 
in the world has probably been not less than one hundred square 
miles. As the land thus destroyed was of average fertility, the 
loss of food-giving capacity has been sufficient to diminish in a 
noteworthy w^ay the population-sustaining value of the country. 
Against the invasions of the sea, whether they arise from the 
direct assaults of the waves and the currents which the winds 
produce or by a combination of subsidence and wave-action, 
there seems to be no effective means of protection. The skill of 
the engineer, applied at great cost, may arrest or dela}'- the loss 
at points where the safety of harbors or towns is involved, but 
tliere is no reason to suppose that it will ever be found economical 
to protect the sea margin from wasting where the defenses are 
merel}’’ to save agricultural land. Our own coasts, particularly 
that of New Jersey, are strewn with wrecks which mark the 
failure of ill-directed efforts to ward off the persistent assaults of 
the waves. At certain points in eastern Massachusetts I have 
found it wortli while to advise tlie owners of houses on the sea- 
shore where their ground was endangered I)}’’ the inwashing of 
the shoreline to heap the sea front with large boulders drawn 
from the neiglil^oring fields. In somewhat protected positions 
the waves l>reaking on this artificial beach are fended from the 
cliffs. Thus by giving the sea-dogs a bone they could for a time 
be kept from their ravages. Where the waves do not attain the 
coastline witli a height of more than five feet, this ine.xpensive 
barrier appears to l;e very serviccalde, l)ut on tlie more open 
shores any boulder that could without great cost he placed on 
the shore would be tossed about and rapidl}" worn to small bits. 
For the maintenance of the precious land, that scat of all the 
higlier life of the world, against the assaults of the waves or the 
more rapid destruction which is hroiight about by the down- 
