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to extend three miles. It derives its name from the green grains of 

 Glaueouitc, which is chemically a hydrated protosilicate of iron and 

 potash. These sands have not been produced by mechanical action 

 alone, for under the microscope many of the grains have been shown 

 to be casts of foramiuifune in glauconile, so instead of being a 

 mechanical deposit in a shallow sea, as so many sands and sandstones 

 are, it may be a very deep sea formation. It is mentioned bj- Dr. 

 Carpenter that in deep sea soundings chalk is found to be deposited 

 to a depth of twelve thousand feet, but below this depth the calcare- 

 ous sliells of the foraminifera; are re-dissolved, and silicious casts of 

 their interiors are found, the original matter liaving been replaced 

 by silica. This is very remarkable, as we percieve at the present 

 time the same operations of nature at work in the deep sea that went 

 on ages ago, when the Upper Greensand was forming at the bottom 

 of the cretaceous ocean. (See proceedings of G. S., for 1877, 

 page 434.) Dr. Dawson states that this giaucouito is similar to 

 the mineral that is found iilling some of the fossils in tlie Silurian 

 beds, and also to the serpentine in the minute chambers of tho 

 Eozoou in the Laurentiau rocks. According to tho same autho- 

 rity such materials are only found in the deeper parts of tho 

 ocean, where the water is eomjiaratively warm, a.s in the Gulf 

 Stream, so that f j^'om the earliest to the present time tho impress 

 of the same creative hand is evident in nature. Some of the 

 blocks of this greensand, -which eastward of Martello Tower No. 

 2, strew the beach, do not appear green on the surface, but ou 

 drawing the point of a hammer across them a distinct green streak 

 is observable. ]\Iauy of these masses are full of cubical pyrites, 

 which glitter ou the dark green back ground of the chimji mineral, 

 like gold. Travelling in a northerly direction along the coast, 

 blocks of chalk are next encountered that have ruUecl down from 

 tho grand clift's, which form a wall, without a break, four hun- 

 dred feet in height and five miles in length, stretching from Folkes- 

 tone to Shakespeare's cliff. JJure tlie botanist will hud as delightful 

 a hunting ground as the geologist. My love of the beautiful must be 

 my apology for mentioning that except over the peaks of snowy 

 mountains I have never seen tlie sky look so wonderfully and beauti 

 fully blue as it does at times when seen over the edges of these 

 white cliffs. In the month of February I have loft ice on the roadsides 

 and the keen winter's air ; at the top of the cliffs, and ou descending 

 to the sea level have found a summer's climate. On a hot summer's 

 morning, wlien there is scarce a breath of air, the sun's rays falling 

 ou these cliffs cause an induced current of cool refreshing air from 

 the sea. Chalk has the great advantage when dry of not being 

 slippery, as it never polishes with tho frequent treading of feet like 

 mountain linuistone and some other rocks ; but there is a reverse to 

 tliis picture, for when a souih-west gale sets in, accompanied as any- 

 thing generally is from that quarter by moisture, the steep paths up 



