4 i8 POPULAR LECTURES AND ADDRESSES. 



South America, and is believed to have fallen 

 there from the sky a fragment made up of iron 

 and stone, which looks as if it has solidified from 



a mixture of gravel and melted iron in a place 

 where there was very little of heaviness ; or this 

 splendidly crystallised piece of iron (Fig. 52), a slab 

 cut out of the celebrated aerolite which fell at 



