Magnetic Spherules — Pettersson and Frederiksson 
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Spherules per kg -sa/t- arc/ car bon ate -free sec/iment 
0 1000 2000 J000 4000 S000 
on the Earth’s surface has repeatedly been 
attacked by various investigators, mainly in 
the United States of America. The method 
adopted has generally been that of introduc- 
ing magnetic "collectors” into the water 
spouts carrying rainwater from extensive roofs. 
The number of magnetic spherules accumu- 
lated in this manner has been counted with 
results which are surprisingly large. Thus 
Warren J. Thomsen (1953) finds the weight 
of such magnetic spheres, from observations 
made at Iowa City, to correspond to a total 
mass of 2,000,000 tons per year for the whole 
Earth. Still higher values have been reported 
by W. D. Crozier (1955) working in New 
Mexico, viz., 35,000 tons per diem during 
August 1955, or nearly 13 million tons for 
the whole year. These figures are several 
thousand times higher than those obtained 
from our counts of the spherules in deep-sea 
deposits. However, neither of the authors 
mentioned could find any trace of nickel in 
the magnetic spheres analyzed. 
We have tried to collect magnetic spherules 
by means of magnetic collectors introduced 
into water spouts mounted at Borno Station 
in the Gullmar Fjord, on the west coast of 
Sweden, and also from the roof of the Ocean- 
ographic Institute in G5teborg. At the latter 
locality we found the number of magnetic 
spherules collected to be very high, whereas at 
Borno the number was considerably less but 
