Lstupart] seismology IN CANADA 71 



waves, which, if regarded as surface waves have an almost constant rate 

 of 3 K second. Dr. C. G. Knott has arrived at thé conclusion that 

 the large waves of earthquakes are transmitted through a comparatively 

 homogeneous medium beneath the crust, which, as they pass is forced 

 10 rise and fall like a raft upon an ocean swell. The reality of these 

 eai-th billows is well illustrated by our magnetic curves from the Agin- 

 court Observatory. See curves. 



