230 THE POPULAR SCIENCE MONTHLY. 



tiny sea was dotted with an archipelago of islands, whose nearing 

 shores, gradually joining, formed chains of islets ; how the inclosed 

 area of water contracted, and, in the union of all their separate figures, 

 vanished. The wet surfaces, broken by depressions, were marked by 

 pits of water from whose sides stole along intermediate creases, thread- 

 like lines of water, the river system of the miniature continent, its 

 sinuous shores impressed by the ripples of a mimic sea. The recollec- 

 tion of boyish pleasures becomes touched with a deeper interest when 

 one is taught to recognize in this the picture of what in a larger way, 

 and under cosmic conditions, has happened in the life-history of our 

 own sphere, and to realize that his childish hand may have repro- 

 duced at will a somewhat exact coj^y of the stages of the world's 

 growth. 



Suppose this little Avorld so briefly made had been left till the 

 bright sunshine had dried its surface, in some places parched and 

 cracked it, in others evoked a luxuriant growth of grass and flowers, 

 filled its shores with gliding snails and its level mead with teeming 

 ant-hills. Once more the running stream is stopped, and slowly the 

 muddy tide rises higher and higher, obliterates the lowlands and 

 creeps slowly up the sides of the high ground, around the skirts of 

 its pygmy mountain-chains, and rolls restored amid groups of remade 

 islets. Under the guidance of this retrospective knowledge let the 

 current be arrested to permit some portions of that first-made land 

 to remain uncovered. With favorable conditions, as a stream car- 

 rying abundance of fine silt, the water moA^ng sluggishly over the 

 inundated surfaces will drop its earthy burden upon them in thin, 

 loose layers, evenly at first, but, as shallows are formed, irregularly 

 modified, or as sudden freshets produce stronger currents, eddies and 

 ripple-bars gather or disturb the sediment. New lands in wet banks 

 and knobs will begin to appear over the highest ridges. Break away 

 again the barrier, and cause the water to recede, exposing in a simi- 

 lar succession of phases the bared surface. The expectant eye now 

 notices certain changes : old landmarks are removed from sight, val- 

 leys have been converted into plains, new hills have arisen, lakes 

 are seen here and there where before was dry land, new contour lines 

 surround the structural ridges which yet remain, modified indeed, but 

 distinctly recognizable, while the low verdure of grass and the numer- 

 ous pinnacles of ant-hills have together disappeared beneath a uni- 

 versal blanket of mud. Only upon the very highest points do the 

 scattered remnants of the first surface appear unchanged, because they 

 alone were exempted from general flood. Again the sun shines upon 

 it, new seeds sprout, other insects flourish, and fresh showers fall. In 

 spots the old land is exposed ; the new having been washed away 

 from it ; it may be easily recognized by its fauna and flora, the 

 drowned ants, and the hidden grass. 



Again and again, under varying conditions, may our experimental 



