From this easily comprehensible representation also everybody, who is just somewhat pure in spirit, will easily see that to determine the where of the center of gravity of the earth firmly, would be not only flatly impossible, but a purely ludicrous and foolish thing. Only so much can be determined approximately for now and at most for a next year or at least acceptably indicated that the center of gravity is approximately in the area under Iceland, a part of Norway, Sweden and Lapland; is nevertheless so active that it can extend it's pulse movement in a certain way even to under Kamchatka and also on the southern side into the area under the Mediterranean Sea. – The Earth, Chapter 3, Paragraph 10