IOWA ACADEMY OF SCIENCES. 35 



prospect of an end," a conception of the immensity of time 

 that reminds one of Lyell and Darwin. The older continents 

 crumbled away and their fragments were scattered over the 

 floor of the sea. There were periods of convulsion when the 

 land rose and the water receded, but he takes no account of 

 subsidence of the land. Hutton suspected the igneous origin 

 of granite on the theory that the granite had risen in the molten 

 state from the molten interior of the earth. He explored the 

 mountainous regions of Scotland and found numerous instances 

 where granite had intruded the limestone and shale from below. 



On the theory of a molten interior he explained foldiogs, 

 faults, and fractures of strata and accounted for volcanoes. 

 Forty years later his theory, remodeled almost outof recogni- 

 tion and elaborated in the light of accumulated evidence, 

 appeared in Lyell's Principles of Geology. 



Though fossils must have attracted the attention of the ear- 

 liest observers of nature, strange as it may seem to us they were 

 generally regarded as freaks of nature or as forms cast up in 

 the deluge of Noah, until about the middle of the last century. 

 At this time Gtittard figured and described some hundreds of 

 them, argued at length that they were the remains of living 

 beings and poinled out their analogy to existing forms. 



Fossils were used as an aid in the recognition of strata by 

 Lehmann, Fuchsel, Werner and others, but they were not rec- 

 ognized as the key to stratigraphy until about 1800, and this 

 recognition was due chiefly to William Smith, Cuvier and 

 BroDgniart, who are regarded as the founders of stratigraphy. 



Smith, who most nearly resembles the modern geologist as 

 we understand the species, began his observations in 1794 while 

 a canal engineer. His first card of the English strata was 

 privately circulated in 1801, and his great map covering the 

 whole of England appeared in 1815. The joint paper of Cuvier 

 and Brongniart appeared in 1808, a year after the founding of 

 the Geological Society of London. 



Such are a few of the facts. Before 1800 Geology had no 

 name or habitation, or recognition as a distinct science, but was 

 regarded as a branch of physical geography or mineralogy. 



To the layman the Geology of 100 years ago appears as a 

 fragment or a collection of fragments. Magnificent as some 

 of its theories were, they were in the early stages of hypoth- 

 eses. To make a science more facts were needed, and they 

 would have to be harmonized by a judiciously critical and 



