INTRODUCTION. 
--♦- 
A GLANCE AT THE PAST. 
“ Und nocli Niemand hat’s erkundet, 
Wie die grosse Mutter schafFt; 
Unerforschlich ist das Wirken, 
Unergriindlich ist die Kraft.” 
SCHILLER. 
Underlying tlie childlike simplicity of the Mosaic account of the 
“ Creation,” there is a dim intimation of what must actually have 
taken place. “Days” must indeed have passed ere our earth was 
ready to receive its most beautiful creatures; the “Firmament” 
must have expanded from the “waters;” Light must have rent the 
veil of Darkness; there must have been trees and plants;—long 
before Birds—those light children of the air—took up their abode on 
our planet. All that is told us is true: what we simply have to do is, 
to understand that truth, to interpret that story. 
Science has, in our time, succeeded in giving us this explanation. 
The different strata of the earth have become pages of a book, which 
are read by the learned with intelligent delight. Short, indeed, is the 
distance which history carries us through the past, in comparison 
with that guidance we owe to the geologist. We know, with some 
degree of certainty, at what epoch the different forms of life first saw 
light on the planet which we inhabit, and thereby can determine the 
period when Birds, with which we shall be exclusively occupied, first 
showed themselves on earth. 
I deem it not unnecessary, briefly to introduce to the notice of my 
readers, the result of the researches of our savants concerning the 
origin of terrestrial life. At the outset of creation, when the gases 
