STREET PAVEMENTS. 543 
One of the projects for surmounting the barrier presented by the Alleghany 
Tange was to construct a canal tunnel, about five miles in length, from the upper 
waters of the Juniata River to those of the Conemaugh River, and singular as it 
•may seem half a century afterwards this project was abandoned because of the 
limited supply of water. Some idea of the volume of transportation can be 
formed from the fact that in the summer of 1834 1,220 boats passed the town of 
Huntingdon, showing the vast amount of freight carried at that early day, in 
the history of internal improvements. I am indebted to the Hon. J. Simpson 
Africa, Secretary of Internal Affairs, Pennsylvania, and John Dougherty, Esq., 
for valuable data in the preparation of this article. 
STREET PAVEMENTS. 
THEO. S. CASE. 
A most important subject in a growing city is the construction of its streets, 
i. e., their grades and their paving. The former are controlled largely by 
the topography of the city itself, and the latter should be governed by the 
former; also by the various questions of utility, adaptability of home material, 
cheapness, durability and hygiene. For a city to remain in the mud when any 
kind of paving material, that will lift her out of it, is accessible, is not only incon- 
venient and disagreeable, but it is expensive. Business, which governs everything, 
first demands facilities involving speed and cheap handling of heavy loads. The 
mud-pike is evolved from the ordinary dirt-road, the corduroy road is the natural 
precursor of the plank-road, the gravel-road precedes the Macadamized road, then 
follow the Nicholson pavement, the cedar-block, the Russ or Belgian stone-block, 
the Medina sandstone, the asphalt. Each in its turn has its advocates and its 
day, and each in its turn is denounced for its faults and abandoned for its succes- 
sor. Each, however, has its advantages and adaptabilities to particular localities, 
but when the tide of fashion or prejudice or favoritism comes along these attri- 
butes are lost sight of. 
In cities that have passed the formative stage and are settling down into 
permanency, the principal materials used in paving are wood and stone, with all 
manner of experiments upon combinations, shapes and construction ; and it is 
somewhat singular that the errors of cities have very little weight in preventing 
their repetition in others. While wooden blocks are being thrown out as worth- 
less in Washington, they are being largely laid down in Chicago, Kansas City, 
and even in London. While stone is strongly urged as the only permanent ma- 
terial in some of our western cities, it is regarded by the best engineers in some 
of the eastern cities as second to asphaltum blocks and even to wood. The fact 
is that the circumstances of chmate and topography, together with the proper or 
improper manner of construction, are factors too little considered both by engi- 
neers and city governments. Wooden pavements are laid on wet foundations, 
tslippery stone blocks on steep grades, and contractors are permitted to evade the 
