glaciers of the alps.

INTRODUCTORY.

( 1 .)

the autumn of 1854 I attended the meeting of the'Wish Association at Liverpool; and, after it was over,failed myself of my position to make an excursion into^ orth Wales . Guided by a friend who knew the country,^ e came acquainted with its chief beauties, and concludede expedition by a visit to Bangor and the neighbourings a |e quarries of Penrhyn.

slat 1 " 0111 boyhood I had been accustomed to handle; had seen them used as roofing materials, and had, <e o the usual amount of arithmetic upon them at° oi > but now, as I saw the rocks blasted, the brokenther ^ r6IQ0Ve< ^ to the sheds surrounding the quarry, anda ndl C ^° Ven b^to thin plates, a new interest was excited,ord' C ° U ^ n °t help asking after the cause of this extra-p 0i ;-'y property of cleavage. It sufficed to strike the(_ 0 U °b an iron instrument into the edge of a plate of rockful\' CaUSe ^ le Inass to yield and open, as wood opens inauce of a wedge driven into it. I walked round thee - r . an b observed that the planes of cleavage werein ere Parallel; the rock was capable of being split, 6 c lre °tion only, and this direction remained perfectlyTw^ ° 1Igb ° Ut the entire quarry,com ^ b uzz ^ G( b and, on expressing my perplexity to mypanion, he suggested that the cleavage was nothing