THE LONG ROAD 
cene times they were nearly all flat. The arched 
foot, too, comes in; this is an advance on the flat 
foot. The bones of the palms and soles are not locked 
until the later Tertiary. The vertebral column pro- 
gressed in the same way, from flat to the double 
curve and the interlocking process, thus securing 
greatest strength with greatest mobility. . In the 
earliest life locomotion was diffused, later it be- 
came concentrated. The worm walks with its 
whole body. 
Iv 
If we figure to ourselves the geologic history of the 
earth under the symbol of a year of three hundred 
and sixty-five days, each day a million years, which 
is probably not far out of the way, then man, the 
biped, the Homo sapiens, in relation to this immense 
past, is of to-day, or of this very morning; while the 
origin of the first vertebrates, the fishes, from which 
he has arisen, falls nearer the middle of the great 
year. Or, dividing this geologic year into four di- 
visions or seasons, primary, secondary, tertiary, and 
quaternary, the fishes fall in the primary, the rep- 
tiles in the secondary, the mammals in the ter- 
tiary, and man in the early quaternary. 
If the fluid earth hardened, and the seas were 
formed in the first month of this year, then probably 
the first beginning of life appeared in the second 
month, the invertebrate in the third or fourth, — 
March or April, — the vertebrates in May or June, 
Q1 
