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THE VEGETATION OF THE HACKENSACK marsh: A TYPICAL AMERICAN FEN 



result. The fresh water, coming down the rivers and creeks from the interior, 

 could pass out to sea through the sluiceways provided for this purpose, while 

 the mechanism of the gate would prevent the salt water at high tide from 

 flooding the agricultural land. Such a method would lower the water-table 

 throughout the protected marsh, and by a system of drainage ditches the 

 salts deposited originally by the sea water would be leached out of the soil 

 by the rain water. 



In the case of the Hackensack marsh, drainage ditches have helped con- 

 siderably in the amelioration of the wild marsh conditions. This land has 

 become extremely valuable for railroad terminals and factory sites, as much 

 as $4000 per acre having been paid for some of it. The factory buildings 

 have been built on foundations of concrete laid on the top of wooden piles, 

 and the experience of the engineer in the rebuilding of the Venetian Cam- 

 panile shows that such piles, if buried in the muck, may last many hundred 

 years. The Campanile of San Marco was begun before the year 997 A.D. 

 After its collapse, July 14, 1902, the foundations were studied by Sig. Giacomo 

 Boni. The piles of white poplar were 9^ inches in diameter, driven into a bed 

 of compact clay. When these were laid bare during the excavation preceding 

 the reconstruction of the tower, the white poplar piles were found to be re- 

 markably sound, retaining their color and fibrous character. This points to 

 the conclusion that the men who build factories on timber piles in the Hack- 

 ensack marshes, provided the piles are driven properly, need not fear a decay 

 of the piles as long as the air is kept from them, which promotes the growth 

 of bacteria and timber-destroying fungi. This fact is also emphasized by the 

 discovery of undecayed stumps of white cedar trees in situ in certain parts of 

 the marsh, as previously described. Such construction has been found to be 

 costly on account of the depths to which the piles must be driven to give a 

 secure foundation. Pile driving with a reclamation of the marsh land by 

 scientific drainage will solve the difficulty, for D. C. Willoughby, a British 

 engineer who has been working for years in building union railroad terminals 

 on the Hackensack marsh, has come to the conclusion that before the marshes 

 can be extensively used for building operations they must be thoroughly 

 drained. 



