INTRODUCTION. II 



order of nature, and as conditions of that stability 

 of government of the world by which the cre- 

 ations of earlier times have been preserved, and 

 >sed on from one geological age to another to 

 survive at the present day. 



On various parts of the globe, meteorites have 

 been found which vary in weight from a few ounces 



I few tons. Examples of 400 of them are pre- 

 served in the British Museum. Some have been 



.1 to fall. It may therefore be inferred that 

 ever since the earth has been in existence it has 

 probably received such additions of material. 

 Meteorites however do not demonstrate that the 

 earth has been built up of meteoric matter; but 

 they are the only clue of a practical kind to the 

 origin of the globe, which the geologist encoun- 

 ters. 



The iron in meteorites is metallic, usually com- 

 bined with nickel. In the earth iron is rarely me- 

 tallic, and rarely crystallized with nickel. Minute 

 particles of metallic 1 iron are present in the vol- 

 canic rock named basalt, which has flowed over 

 the north of Ireland. Iron is found combined 

 with nickel in the Van mine in Denbighshire. 

 The percentage of nickel in the iron varies in 

 different localities. There is only one or two per 

 cent, of nickel in the great masses of iron, some- 

 times weighing 50,000 lbs., embedded in Basalt at 

 Ovifak in Disco Island, on the west of Greenland. 

 An alloy of these metals found in New Zealand, 

 yields 67 per cent, of nickel. Both are regarded 

 as of terrestrial origin. 



Although the mineral quartz is one of the most 



