IB Mr Stevenson on the Building Materials 



appear to have violated many of the established rules of 

 engineering as practised in this country. The scarcity of 

 stone, and the unsuitableness of brick for hydraulic purposes, 

 for example, has forced them to construct most of the locks 

 and aqueducts on the lines of their great canals wholly of 

 timber, with which the country abounds ; and that material, ill 

 adapted as it may seem to such a purpose and situation, where 

 it is not only exposed to the constant tear and wear occasioned 

 by the lockage of vessels, but also to the destructive effects of 

 alternate immersion in water and exposure to the atmosphere, 

 has nevertheless been found in practice to form a very good 

 substitute for the more durable materials used for such works 

 in Europe. 



The quarries of the United States, taking into consideration 

 the great extent of the country and the number of its public 

 works, are, as I have already hinted, few in number ; and, 

 generally speaking, the workings are on a small scale. They 

 afford granite and marble, and their produce is almost exclu- 

 sively applied to facing public buildings, forming stairs, win- 

 dow, and door lintels, and to other architectural purposes. 



Granite is worked in the northern part of the country at 

 Quincey in the state of Massachusetts, and at Singsing in the 

 state of New York, and also in New Hampshire. The 

 Quincey granite is of a fine grey colour, and can be quarried 

 in large blocks. It has been used a good deal in Boston and 

 the neighbouring country for architectural works. It has also 

 been employed for railway-blocks on some of the lines of rail- 

 way in the neighbourhood of Boston, and in the construction 

 of the only two graving docks which exist in the United 

 States, the one at Boston, and the other at Norfolk in Virgi- 

 nia, the latter at a distance of upwards of 500 miles from the 

 quarries; and these, so far as I am aware, are the only 

 engineering works of any consequence in America in which 

 gi-anite has been employed. 



The Singsing granite, which is of a dark grey or bluish 

 colour, is quarried on the banks of the Hudson, about twenty- 

 five miles from the town of New York, at which place it 

 has been pretty generally used for some time for stairs and 

 lintels, and has lately be«n introduced for facing buildings. 



