PROGRESS OF SCIENCE. 
183 
plants specifically known and determined. 
In the first quarter of the present century 
the facts of our science were still regarded 
by many persons as uncertain marvels, mag¬ 
nified by the haze which surrounded the 
whole subject of geology. Brongniart, in 
1828, collected and methodized the scattered 
labours of his predecessors, and gave unity 
and interest to the study. He enumerates 
501 species, and this number has been in¬ 
creased upwards of three-fold since the 
date of his first publication. 
In the present day no picture of physical 
life can be complete without a represen¬ 
tation of the earth’s ancient flora; it brings 
its contingent force to the great army of 
phenomena, by which the faculties of our 
intellectual and moral being are challenged 
to investigation. 
Considering the extensive size of its field, 
and the little time yet spent in its culti¬ 
vation, it may appear premature to enrol 
the facts already diseovered, and reason from 
the qualities of their proportions ; but the 
tables constructed from present discoveries, 
are probably very near approximations to 
