bi "erth" sumwon must meen the land that stik up abuv the water.
Siens kan gage distans apart av transponders on land...Sat up in ski
Wen its in raenj av transponder in North Amerika & 1 in Greenland, it send
signal tu both & get respons. From time it take tu get anser, it kan figger out
distans. Then keep rekords over bout 10 yeers & lo, em drift apart very fast
sumtimes as fast as 3 inch per 100 yeers.