532 



POPULAR SCIENCE MONTHLY. 



the surface is covered with half an inch of clean coarse sand or 

 granite screenings. 



Improved wood pavements are a luxury. They have many 

 points of superiority over asphalt. They are so considered in Lon- 

 don, where their use is continued, although they require renewal 



A iS'kw C'kdak Block rAVEiiKNT in ToKoNiy. 



oftener than asphalt, and much more often than granite. They 

 will undoubtedly be used more frequently in this country when the 

 people are willing to pay the additional cost for the quiet and free- 

 dom from dust and from the somewhat disagreeable glare of asphalt. 



For a dozen years or more brick has been used for street pave- 

 ments in the cities of the middle West, The use of this material 

 is by no means new. It began in Holland in the thirteenth cen- 

 tury, and in the seventeenth century the highway from The Hague 

 to Scheveningen was paved with brick. In Amsterdam such pave- 

 ments are said to last from ten to twenty years, or an average of 

 fourteen years. After about ten years they are commonly turned 

 over and relaid, after which they will last about four years more. 

 The size in common use is about the same as that made in this 

 country. 



A good paving brick sIkhiM Ik- tough enough to withstand the 

 wear to which a street surface is subjected without chipping or 

 cracking, and should not absorb more than from two to four per 

 cent of its weight of water after submersion for forty-eight hours. 

 It has not the wearing qualities of granite, although there is 

 one block on Ninth Avenue, in the Borough of Manhattan, which 

 has been subjected to very heavy traffic for eight years, has had 



