: Editors’ Table. 869 
_ without hesitation any system of education which commences, as 
nature commenced, with microscopic objects, and with processes 
which are as yet unclassified. The thirst for the unknown will 
develop, and it should be led along by a process of satisfaction 
before it is brought to that frontier line where all the resources of 
knowledge and method are necessary to progress, 
— The earthquake which visited the eastern part of North 
- America on August 31st is one of the most remarkable in our 
history, both in its extent and in its serious results to the south- 
eastern portion of the country. Its occurrence naturally excites 
inquiry as to the possibility of our being more frequently visited 
than heretofore by this scourge. The numerous earth-trembles 
destruction as has visited Charleston we must, if possible, provide. 
It is well known that there are lines of abrupt change of the 
geological structure of the earth’s crust, which are known as 
faults. These are more or less elongated fractures, on one side 
of which the strata occupy a much higher position than they do 
on the other. The depressed side may not receive deposits of 
Much thickness subsequent to the fracture. If in this case the 
elevated Side is not removed by erosion, a range of monoclinal 
_ Mountains is the result. If on the other hand deposits are laid 
_ Gown on the depressed area, and the elevated tract is mowed 
down by “frost and fire,” the mountain range disappears and 
none but the geologist can detect the fault or fissure. ; 
“he shrinkage of the earth is supposed to have been the cause 
“teas elevation of many mountain ranges, which are wrinkles of 
ate nearly always produced. Such abrupt changes of structure 
scr at or near the sea-borders of most continents. The de- 
Pressed region is occupied by the sea, and by the deposited mate- 
"al which flows into it from the shore. 
| It commences at the sea-coast at Staten island and 
*xtends south-west near to Trenton, Philadelphia, Wilmington, 
Ca, etc, This is a very important line in the economy of the 
‘“ountry, Here the hill-country ceases and the plain of the sea- 
Þegins. In many. of the States it marks the head of tide- 
ommon to all countries are of little moment, but against such 
“cur, In the formation of the greatest changes of surface they © 
Such a line of fault extends throughout the Eastern United — 
Del, Baltimore, Washington, Richmond, Raleigh, Columbia S. 
