i6o Report S.A.A. Advancement of Science. 



side, where pressure is at a maximum, or the side from which bad 

 weather might be expected. 



The most general and popular use of this instrument is that it 

 yields records of all the great seismic disturbances in the world. 

 From the character of a seismogram you can judge of the magnitude 

 of the earthquake it represents. You can frequently say where it 

 occurred, and when it occurred. This information is usually obtain- 

 able long before the arrival of cablegrams which, if they emanate 

 from a devastated district, suffer not only delay, but may convey 

 exaggerated and alarming impressions. Seismograms written by our 

 earth have frequently extended, confirmed, or disproved telegrams 

 written by man. To pressmen and the inquiring public seismograms 

 have an increasing importance, and Africa, although it is the poorest 

 earthquake-producing continent in the world, can with advantage to 

 itself report upon disasters off and beyond its shores. 



Large earthquakes are announcements of accelerations in 

 hypogenic activity. When this ceases, and that which is epigenic 

 becomes paramount, it would seem that the ultimate effects of surface 

 denudation in general would be to reduce continents to sea level and 

 to wipe out surfaces which are habitable. The panacea for such a 

 fear rests in the idea that as mountains are washed down to load our 

 sea boards, these may sink, whilst the high lands, which have been 

 lightened, would be buoyed up. By such a process isostacy would 

 save the features of our world. 



