LITHOLOGY. 121 



CABINET SPECIMENS. 



For future reference specimens should be taken from 

 a part of the rock observed in a quarry or elsewhere 

 which presents in a typical manner its noteworthy 

 features. They should represent the average colour, 

 show distinctly the crystals, grains, or laminae, and, if 

 practicable, on one side a weathered surface. Pieces 

 about one and a half inches in length by one inch in 

 width and thickness are of convenient size, but these 

 must be as nearly as possible straight-sided and rect- 

 angular. When first detached and chipped into form 

 each specimen must be wrapped in paper with the 

 locality and formation (if possible the very bed) whence 

 derived written thereon. A collection of rocks or fossils, 

 simply as such and without their original locality being 

 known, is for scientific purposes utterly valueless. 



After all necessary tests have been applied for deter- 

 mination at home, each specimen should be labelled, or 

 numbered with reference to a list the label or reference 

 setting forth the kind of rock, the formation (or bed) 

 from which it came, and the locality, in this or other 

 convenient form. 



Eock. Oolitic Limestone. 

 Formation. Great Oolite. 

 Locality. Box Tunnel. 



