148 farmers' and mechanics* journal. 



Farmer, vol. vi. p. SQQ.] may be as correct there for June as what 

 we have said for September here. But the fact that timber trees 

 do cease to extend their branches in June, and form their buds on 

 the banks of the Delaware, would be gratifying for me to learn. 

 One other fact would be useful to ascertain — that is, whether there 

 is the same acid in timber trees in June that there is in September. 

 In this latitude, timber that is felled in September, will not sutTer 

 from red-rot ; nor will the powder-post worm ever touch it. Take 

 a young walnut, say one large enough for barrel-hoops, and give it 

 any exposure you please (not placing it in the fire) and it will not 

 lose its force in two years ; nor will the powder-post be found upon 

 it, whereas take it in June, and it will perish the first season. 



I have subjoined a table, showing the comparative value of tim- 

 ber felled at the two seasons of the year above mentioned, in which 

 I am correct, or nearly so : 



Oak, Sept. 10.0 June 4.5 



Maple, Sept. 10.0 June 2.4 



Walnut, Sept. 10.0 June 2.5 



Elm, Sept. 10.0 June 1.6 



Ash, Sept. 10.0 June 3.2 



But by comparing the four last with white oak, provided they 

 lyere all felled in September, they will stand nearly thus : 



Oak, 10.0 Maple, 5.5 



Walnut, 6.2 

 Elm, 4.5 



Andover, June 29, J 828. 



Ash, 5.6 



Phineas Stevens. 



On the Causes of Dry Rot in Public and Private Ships, and its Re- 

 medy. By J as. Barron, Esq., of the United Stales Kavy. 



A Pamphlet under the above title has just been published iq 

 Norfolk, by Commodore Barron, The subject has been repeat- 

 edly noticed in this Journal, \_Frankliyi Journal, edited by Thomas 

 P. Jones, M. D.,] and from the great increase and extent of the, 

 evil proposed to be remedied, demands the utmost attention. We 

 shall make a brief abstract of the former, and give to pur readers 

 the whole of the latter part of the pamphlet. 



The dry rot is attributed to the influence of foul air extricated 

 from the bilge water ; and the remedy proposed is the free supply 

 of wholesome air, by constructing the vessels in such a way that it 

 may have free access to the timbers. The deleterious effect of 

 foul air upon vegetable bodies, is viewed as analogous to its action 

 upon animals. 



" The most positive proofs (says the Commodore) of the destruc- 

 tion occasioned to timber by a foul atmosphere, are to be seen in " 

 every ship that is found in a decayed state ; the best timber con- 

 nected with the interior, being more oi less injured, while that, 

 -6ven of an inferior quality, situated on the exterjor, will be foi^nd 



