452 NINETEENTH CENTURY* PT. TII. 



coast of Yorkshire and Norfolk, huge masses of glacial drift, 

 as it is called, made of mud and stones confusedly mixed 

 together, which were dropped from icebergs travelling south- 

 wards from the ice-fields. 



This period of cold is called by geologists the ' Glacial 

 Period ; ' and when you read works 'on geology you will see 

 that it explains in a wonderful manner many curious facts 

 in the later history of our earth, and the distribution of 

 plants and animals upon it. For the present it is enough 

 for you to remember that Agassiz first pointed out the signs 

 of this cold period, and that this discovery was one of the 

 earliest rewards of a patient study of causes which are going 

 on now; for it is from the ice-action in Switzerland and 

 Greenland in the present day that we are able to under- 

 stand how these huge ice-fields carried . down erratic blocks 

 and the mud of moraines during the Glacial Period. 



Geological Proofs that Man lived upon the Earth 

 in Ages long gone by, with Animals which are now 

 extinct, 1847. The second remarkable discovery which 

 has been made in geology in this century is that of the 

 antiquity of man ; or the fact that man must have existed 

 upon our earth long before the very earliest times of history 

 or tradition, in an age when an elephant and a hyaena, of 

 extinct species, roamed about England and France, together 

 with some other strange animals which are not now to be 

 found upon the globe. 



This discovery, which was not believed for a long time, 

 was first announced by a French geolog ; st, M. Boucher de 

 Perthes, in the year 1847. It happened that near this 

 gentleman's house, at Abbeville in Picardy, gravel-pits had 

 been dug from time to time for repairing the fortifications 

 of the town, or mending the roads. During these excava- 

 tions, in the beginning of the century, a great many bones 



