BOWLDERS AND METEORITES. 99 



and whiit is their history? Chemical examination discloses 

 the ftict that all rocks are remarkably simple in their composi- 

 tion, and, in fact, simplicity is stamped upon everything in 

 the air, the waters, and the solid framework of our planet. 



Half of the earth's crust is formed of one single element, 

 and a quarter of the remaining half is formed of one other 

 element. There appears to our superficial observation great 

 complexity in rocks as regards nature and composition, but 

 in this we are mistaken. There are three distinct kinds of 

 granite, but they are formed by holding in excess some one 

 single ingredient. But I cannot dwell upon the chemistry of 

 rocks. 



To return, we find, as I have said, these bowlders upon 

 our farms, and we are forced to conclude that they belong to 

 a class of rocks not indigenous to our localities ; and hence 

 a natural desire is awakened to know something of their prob- 

 able history. 



In some sections, intelligent farmers have traced bowlder 

 rocks long distances, and found in situ the bed-rock from 

 wliich they were taken. Geologists have often done this, 

 and proved the identity of specimens transported many miles. 



We must admit, I think, that these loose rocks found upon 

 our farms have been left in their present positions by some 

 transporting agency exerting great force. They are a long 

 way from home ; they are strangers in our fields. How came 

 they there? In the view of some farmers, they must have 

 come from above, — rained down from the spaces over us. 

 This cannot be so. It is true, there are rocks having a 

 celestial origin ; they are called meteorites. 



It is probable that accessions to the rock masses upon our 

 earth have been made to the amount of several million tons 

 of meteorites during the past ages, but they all have a distinct 

 and peculiar character and composition. They are unlike our 

 field rocks, and cannot be mistaken for them. I have in my 

 hand a portion of a meteorite which is exceedingly interesting 

 to us all, I trust. It is peculiar in its nature and history, and 

 will well repay examination. In looking upon it, it is impos- 

 sible to help asking. From whence came this rock ? It is a 

 fragment from the great Iowa meteor, which fell on the twelfth 

 day of February last, and was sent to me by Prof. Irish of 



