664 TRANSACTIONS OF THE 



In the experiments tried a few years since in Broadway, neai 

 Chambers street, I observed that the hexagonal blocks which 

 were placed with the ends of the capillary tubes exposed seemed 

 to wear remarkably well, and i could only account for it by 

 supposing that the iron from the wheels wore off', and filled the 

 tubes with grit, thus not only preserving the wood, but at the 

 same time converting it into a sort of file, with which to wear 

 away the substance of its strong neighbor, iron. Then, again, 

 the perishable quality of all varieties of wood, is owing to the 

 fact, that they abound in nitrogen, which in this case, the blocks 

 being placed in a vertical position, was washed by the rains, 

 through the tubes, into the earth, which had a strong affinity for 

 it. And upon the whole, I am inclined to believe, that wooden 

 pavements, in some shape or other, will eventually supersede all 

 other varieties, and become the favorite material in all great 

 thoroughfares. The inconveniences produced in London, by 

 reason of the wear of all kinds of pavements hitherto adopted, 

 causing frequently a suspension of intercourse while repairs were 

 going on, then they in turn were dusty, muddy, intolerably 

 noisy, &c. This excited much inquiry as to the feasibility of 

 building some road sufficiently strong and durable to accommo- 

 date the enormous traffic, and at the same time to prevent the 

 necessity of constant repairs. The problem was solved, and a 

 wooden pavement throughout the length and breadth of Oxford 

 street was the result, and this plan has been adopted in many 

 other thoroughfares in London, also in Vienna and St. 

 Petersburgh. 



I have seen the following plan somewhere for an iron pave- 

 ment, which consists of circular cast iron rings, about twelve 

 inches in diameter, and six inches deep, divided into seven com- 

 partments, one in the centre, and six surrounding it, rendering 

 these apertures sufficiently small to prevent the catching of the 

 hoof of a horse. The upper edge of the ring, and all the partitions 

 are thickly indented with semicircular depressions, about an 

 inch in depth, a protecting hub on one side of the ring, and a 

 corresponding depression on the other, fit together, and thus lock 

 the whole road into one solid framework; the indentations on the 



