GEOLOGICAL INTEREST NEAR MEDICINE HAT. 155 



Specific gravity — 1.3972. the weiglit of a solid cubic foot being 

 87.32 pounds 



The composition of this coal indicates that it is a lignite, showing 

 a considerable ])roportion of water and ash and a tendency to dis- 

 integrate when exposed to the air. A comparison of this coal with 

 tiiat derived from seams nearer, and in the Rocky Mountains, shows 

 the latter to be freer from water, gives less ash and a nuich higher 

 p?rcentage of carbon, in other w^ords the quality of the coal improves 

 as you aj)proach the nijuntains. In the iron-stone band near the 

 rivei- several interesting fossil plants were found in the fragments 

 of stone. These are well defined and in many respects can be readily 

 o!)served to be closely related to the genus Biosenia and the species 

 has heen given tlie name Brosenia antiqua by Sir William Dawson 

 to whom some specimens were shown. These before you were 

 obtained near the river's edge. On account of the gradual slope 

 from the prairie level down the ravine to the river's edge, it is an 

 easy matter to examine the different layers of de|)Osits indicated in 

 t'le .section already referred to. The fossils from the bed almost two 

 liiiiidred feet below the level of the prairie can be readily identified 

 as allied to the oyster family. They are not imbedded in solid rock, 

 but foi-m a layer of loo.se shells Iving between beds of clay ; they 

 are exceedingly fragile, usually small and require to be handled very 

 carefully, or they crumble to pieces on examination. 



From m my gathered, the specimens before you are the only ones, 

 which have remained at all complete. 



The pi-esence of oyster shells so far below the prairie level, in a 

 region now removed 2,0'JO miles from the sea is very suggestive of 

 the wonderful changes which that country has undergone in the ages 

 long receded into the i)ast. At several places along the banks of the 

 river, the remains of petrified trees are veiy common ; some of these 

 b;dong to types entirely different from those which now grow on 

 the bulks of the S iska'chewan. 



The clay band 110 feet above the river in some places pre.sents a 

 very attractive appearance, being almost as red as vermilion ; a con 

 dition which has likely resulted from the burning of coal in the 

 seam below. 



