36 THE MODERN PERIOD. 



matter by growing vegetation from the air and water. Secondly, The 

 ve«-etable matter iu bogs, forming a black carbonaceous mass, has 

 entered on the first stage of the changes by which it may be converted 

 into coal ; and it is not nnnsual to find in the bottom of such bogs 

 a substance much resembling ordinary bituminous coal. Thirdly, 

 The organic acids produced by the vegetable matter, when long 

 saturated in water, remove from the subsoil of the bogs the oxides of 

 iron and manganese, as well as lime and the other alkaline earths ; 

 hence the subsoils of bogs usually consist of bleached whitish sand or 

 clay of a very unproductive character. There are a few exceptions 

 to this in localities wliere the soil contains a very large proportion 

 of lime. On the other hand, when the underlying rocks contain 

 bi-sulphuvet of iron, as is the case in some parts of the slate districts, 

 the sulphuric acid produced from this mineral gives a still greater 

 degree of acidity to the bog, while the iron is sometimes in too great 

 quantity to be removed entirely. Fourthly, The iron and manganese, 

 removed in the manner above mentioned, are deposited, usually in 

 rounded kernels, at the outlets of such bogs, or in the soils through 

 which their waters soak, and become partially exposed to the air. 

 In this way small quantities of bog iron ore and bog manganese ore 

 are formed in the vicinity of many swamps. All these facts respecting 

 bogs have their analogues on a large scale in our ancient rock 

 formations, and more especially in those of the carboniferous system. 

 The bogs when drained, and their surface dressed with sand, or 

 sand and lime, to supply the silicious and calcareous matter in which 

 they are deficient, are excellent soils, second only to diked marsh 

 in their productiveness in hay and oats. Portions of bog have already 

 been reclaimed in this way in several of the counties, and there can 

 be no doubt that many tracts of this description, more especially in 

 the less fertile portions of the province, require only the application 

 of skill and industry to render them valuable. 



In describing the modern deposits, I should not omit those of 

 blown sand, Avhich occur somewhat extensively within the region 

 to which this work relates. Sable Island is the highest part of one 

 of those banks of sand, pebbles, and fragments of shells and coral, 

 which form a line extending under the waters of the Atlantic, and 

 parallel to the American coast, from Newfoundland to the vicinity 

 of Cape Cod ; and which are separated from the coast and from each 

 other by valleys of mud. Sable Island Bank is one of the largest 

 of these submarine sand-beds. Its area is equal to one-third of that 

 of Nova Scotia. The depth of water at its margins varies from 35 to 



