Polytechnic Association Proceedings. 569 



walks (if necessary), would afford perfect daylight to the street 

 and stores below. 



The excavation and construction may be begun and carried on at 

 many points along the route at the same time, and temporary, 

 movable bridges will prevent any obstruction to travel during the 

 progress of the work. 



A detailed statement, made by competent engineers, shows the 

 entire cost of the road to be about $2,000,000 per mile, which is 

 one-third less than the cost of the Loudon tunnel roads, owing to 

 the great expense of their ventilation. 



Route. — The route proposed for the road is the line of Broad- 

 way, from the Battery to the Central Park; thence by a suitable 

 route to connect with the Hudson River railroad; also with a branch 

 from Union Square to connect with the Harlem railroad. 



Advantages. — 1st. Having four tracks, it affords rapid transpor- 

 tation for both freight and passengers, with full accommodation for 

 the way travel, thus completely relieving Broadway, an advantage 

 not even claimed for any other plan. 



2d. It combines the advantages of both the tunnel and elevated 

 ways, and avoids the disadvantages of each, being strong and safe 

 and admitting of rapid speed, and at the same time being airy, 

 light and pleasant for travel. 



3d. That access to and exit from the road, and to and from the 

 cars, will be more easy and attended with far less difficulty than at 

 the present time, to and from the street cars or omnibuses. 



4th. The surface roadway will be greatly improved both in 

 appearance and utility, and there will be comparatively no dust in 

 dry, and no mud in wet weather. All surface water would be con- 

 ducted to the sewers through the hollow columns of the arcade. 



5th. Pedestrians will find the sidewalks less crowded, and the 

 lower one will be sheltered from the storms of winter and the sun 

 in summer. Being thus free from the snow and rain, dust and heat, 

 it will become a safe and pleasant promenade. 



6th. The water and gas mains being so easily accessible, can be 

 repaired, and the distributing pipes connected without disturbing 

 the streets. 



7th. The sewerage of the city will be greatly improved, and can 

 be opened and repaired with facility and without any inconvenience. 



8th. The whole work is to be accomplished without requiring 

 any sacrifices at the hands of property owners, and without the 

 expense of a dollar to this over-taxed city. 



