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wet, than would drain them, by the 

 means of open drains or ditches, which 

 are not only abundantly the most cheap, 

 but the only sort that can be effectual, 

 except very large covered ones, as the roots 

 would soon close up any other.^^ 



* Part of a stone conduit of nine inches square, 

 made to convey water to the town of Halifax, was 

 completely closed up in three years, by the Roots of 

 some Sycamore Trees, which grew near it. The stone 

 was then taken up, and a wood trunk, of the same di- 

 mensions, put in its place, when that also got filled 

 up by the same means, in a like space of time. In somtr 

 places, it was effected by a single fibre getting into a 

 joint, no larger than sufficient to admit a crow quill, 

 many hundreds being produced from such fibre, as 

 large as itself. In some instances this happened at a 

 distance, more than twice the whole length of the 

 trees. 



Perhaps some persons may think this account dis- 

 credits the theory just advanced, in regard to wet 

 soils ; but such is not the case : for as the roots in the 

 water bore but a small proportion to the whole, the 

 rest being in a very dry soil, the former would collect 

 and distrjjjute moisture to the latter; which would in 

 turn supply them with what they collected from the 



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