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as the current varies. There is one invariable rule about these 

 false-bedding planes, and that is that they always slope in the 

 direction the material has travelled. If the sand came from the 

 east towards the west, then the inclined layers face towards the 

 west more or less. This can be better understood by imagining a 

 quantity of sand and gravel to be brought out of a railway cutting 

 and thrown down endlong in successive layers as it is when it is 

 employed to form an embankment. The slope of the successive 

 layers of material so thrown down invariably faces in the same 

 direction as the material has been transported. Looking up the 

 slope at the end of the embankment, we should be looking in the 

 direction of the cutting the sand and gravel had been got from. 

 In like manner, if we obtain a series of observations upon the 

 prevailing directions of the false-bedding planes in a rock, we 

 know for certain in what direction the parent source of that rock 

 lay. Observations have proved that, with few exceptions, the 

 false-bedding planes in the Penrith Sandstone slope away from the 

 east, and therefore we know that the source of the material must 

 be looked for in that direction. Now when we trace the Penrith 

 Sandstone away from this point where we now are, in the direction 

 of Dumfries on the one hand, and of Kirkby Stephen on the other, we 

 find certain parts of the rock becoming more and more charged with 

 fragments of other rocks. These fragments, as a rule, we can easily 

 trace to their parent sources, which, in the case of the Westmorland 

 deposits, usually lie to the south or to the south-east of their present 

 positions. The history of the climate of the period is, many 

 geologists think, plainly written upon these deposits, and may be 

 easily deciphered by any one who will set about it in the right 

 way. In a deposit accumulated in the ordinary way, under water, 

 the materials are commonly more or less sorted out according to 

 their respective sizes. Unless the currents happen to be subject 

 to considerable variations in force, they leave little with little and 

 big with big. A current strong enough to roll a big stone along 

 the bed of the stieam carries a smaller one much farther, and 

 leaves the still bigger stones unmoved. More than that, one 

 result of the frequent knocking of such stones against each other 



