294 Streets of the Metropolis. 



are disturbed by these repeatedly-opened trenches ; and the 

 heavy drays and waggons acting as pressers, shake the buildings 

 from their position. 



To avoid such danger and damage, and that the pavement 

 should remain as durable and firmly level as the art and aim 

 of the pavior can make them, it is, above all things, necessary 

 that more labour be bestowed in filling up these openings. As 

 no wise architect would build on loose ground, so neither 

 should pavement of any kind, nor even a common road, be 

 laid on a substratum, which is not sufficiently consolidated to 

 bear whatever weights may have to pass thereon. To obtain 

 this requisite compactness, it is necessary that the material 

 which is dug out should be used or rejected, according as it is 

 or is not capable of being rammed as firmly as possible. In 

 doing this, the temperament of the material, whether sand, 

 gravel, or other substantial earth, should be particularly at- 

 tended to ; it should be neither too wet, nor too dry; if just 

 damp enough to knead together under the action of the 

 rammer, it is in a proper state. Every shovelful thrown in 

 should be subjected to the rammer, from the very bottom to 

 the top ; not a crevice or corner of the mass should escape. 

 This operation carefully executed, as it may be, will ever after 

 bear any kind of paving, gravel, or road metal, without sinking 

 more than the surrounding natural bed of the earth. 



An approach to this rule of management, and to prevent the 

 irregular sinking of the pavior's work, has been done in Fleet- 

 street ; by placing a thick layer of broken stone below the 

 pitching. This will certainly be effectual, where the stones are 

 laid upon a firm bottom ; but where laid on, or mixed with 

 loose, unrammed earth, even this expensive expedient will be 

 found insufficient. 



In some other leading streets, where the Macadamizing 

 system has not been introduced, the paving has been done 

 with great exactness ; regularly cut, nicely squared stones only 

 have been used ; and these, as usual, very smoothly rammed, 

 and afterwards grouted with thin mortar to fill the interstices, 

 and cement the whole together. But in such cases, the exe- 

 cutor will be disappointed ; he trusts too much to the accuracy 

 of the workmanship in placing the stone, and to his powerful 



