AGE OF THE EARTH—JOLY. 289 
Algonkian results and two post-Jatulian results. The Archean re- 
sults by helium and lead can not be located on the base line save by 
the indications of 
the other results. 
If there was 
accord between 
the stratigraph- 
ical column and 
the radioactive 
data, the latter 
should be ranged 
on straight lines 
which necessarily 
pass through the 
origin (present 
time). We find 
them, however, 
ranged upon 
curves. I have 
plotted a rather 
excessive value of 
the age of the 
ocean as deter- 
mined by solvent 
denudation, erect- 
ing for this pur- 
pose an ordinate 
of 150,000,000 of 
years at the begin- 
ning of Algonkian 
time. Joining the 
summit of this or- 
dinate to the ori- 
gin we see that 
the curves for 
helium and lead 
flow into this line 
in recent periods. 
If now we as- 
sume that the 
time indications 
of the lead ratios 
are correct, we are 
presented with the following alternatives as regards the amendment 
of the sedimentary column. 
38734°—sM 191119 
Fig. 1. 
S 
S 
: 
=~ 
8 Ceres 'Orv'Sn 
FALE 02010 
Camozolc 
