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From the Minute Book of the Agricultural Society. 



On the Duration of Posts, when their natural Position 

 is reversed, — Extract of a Letter from Mr, John R. 

 Evans, to the Secretary of the Philadelphia Society 

 for promoting Agriculture^ dated Nov, 29, 1811. 



On removing the old fence of my garden, to set a 

 new one, about five years since, I found that the old 

 fence was supported by a few posts, that were forked, 

 and the fork down, and that they were quite sound, 

 while the rest were rotten, and broken off at the ground ; 

 the yard fence, (only five pannel,) three parts of which 

 were strong and sotmd, and likely to last for ten years 

 more, were not forked, but from their being knotty, it 

 was easy to see that they were top in the ground. I 

 have made enquiry of the carpenter who built the fence, 

 (who is yet living,) and he says the fence stood 20 or 

 21 years, and that it was the design of my predecessor 

 to turn all posts top down, that would admit of it, the 

 fact being known to him that they would last longer.* 



John R. Evans. 



* I have experienced the truth of the fact above stated. I do not 

 pretend accurately and satisfactorily to account for it. I have cou' 

 jectured, that by reversing the vessels in which the sap had been 

 accustonied to circulate, whilst the tree was in life, the moisture 

 drawn up by the sun, in vessels even of dead timber, was impeded 

 by the reversed position. Had the posts been, as they generally 

 are, placed with their butt ends downward, the vessels designed for 

 circulation of sap, might be filled with moisture from the air or 

 earth. However fanciful this conjecture may appear, the fact men- 

 tioned by Mr. Evans, is important, and proved in many instances. 



R. Peters. 



