AGE OF THE EARTH—HOLMES 
trate the lopsided effect of including 
results involving the data for two 
samples of lead of abnormal constitu- 
tion. Certain other abnormal leads, 
however, would give a concentration 
of results on the right. The fact that 
the modal solution remains independ- 
ent of these aberrant results favors the 
hope that an estimate of 3,350 million 
years for the age of the earth is unlikely 
to be seriously wrong. 
SELECTED REFERENCES 
Conway, E. J. 
1942. Proc. Roy. Irish Acad., vol. 48, 
B8, pp. 119-159. 
1943. Ibid., vol. 48, B9, pp. 161-212. 
Henperson, G. H., and Batesson, S. 
1934. Proc. Roy.Soc., vol. 145A, pp. 563- 
581. 
HeEnbeErson, G. H., and TurnBuLL, L. G. 
1934. Proc. Roy. Soc., vol. 145A, pp. 
382-391. 
239 
Homes, A. 
1946. Nature, vol. 157, pp. 680-684. 
1947a. Ibid., vol. 159, pp. 127-128. 
1947b. Trans. Geol. Soc. Glasgow, vol. 
21, pp. 117-152. 
1947c. Geol. Mag., vol. 134, pp. 123- 
126. 
Keevi., N. B. 
1939. Amer. Journ. Sci., vol. 237, pp. 
195-214. 
Niger, A. O. 
1938. Journ. Amer. Chem. Soc., vol. 60, 
pp: 1571-1576. 
1939. Phys. Rev., vol. 55, pp. 153-163. 
Nirr, A. O., THompson, R. W., and Mur- 
PHEY, B. F. 
1941. Phys. Rev., vol. 60, pp. 112-116. 
WASIUTYNSKI, J. 
1946. Astrophys. Norvegica, vol. 4, p. 
225. 
WIcKMAN, F. E. 
1939. Sveriges Geol. Undersdékning, C, 
No. 427, pp. 1-8. 
1942. Geol. Féren. Férh., vol. 64, pp. 
465-476. 
1944. Sveriges Geol. Undersékning, C, 
No. 458, pp. 1-6. 
