CURE OF THE DRY ROT. 5 



If the latter effe6l be required, namely, that the trough Arrangement 

 fiiould ad like a continued feries, the connedion of the troughs ^^l the efteft of 



o 1 .-/v . , . /- 1- - • a fuccefllon of 



mull be differently made. A number of clipping pieces or plates. 



fpring forks muft be provided of copper wire, as reprefented 

 by the curved lines a, b, c, d, &c. from each of which proceeds 

 a third leg or branch, as feen in the figure. Thefe are ap- 

 plied (moft conveniently above, but) not fo as to touch each 

 other; the clipping part of each embracing the dry furfacesofa 

 pair of the zinc pieces, which are aded upon by the fame mafs 

 of acid, while the third leg is immerfed in the acid of the 

 next adjacent cell. Every one of their legs or branches is 

 difpofed towards the fame region or part of fpace ; by which 

 means tbe acid of each compartment ading Upon a pair of zinc 

 plates, on one furface only, is made to communicate, by the 

 interpofition of copper, with the uncorroded fide of the next 

 pair in fucceffion ; and fo on, exadly as in the common trough 

 or pile. 



11.^ 



Ohfervatiorts and Communications on the Dry Rot in Timber, made 

 to the Society for the Encouragement of Arts. 



(Concluded from. p. 318 of Vol. VII.) 



Second Letter from Benjamin Johnson, £/?y. 

 SIR, 



JL HE obfervations I fent yefterday were taken from different 

 parts of my note-book, in hafle, becaufe the fecond Tuefday 

 in December was pad ; for it was by accident I faw the adver- 

 tifementon Saturday j but withing not to be deficient in infor- 

 mation, I trouble you again. 



The leaves of the plant appearing exhaufted and dead, is A more full ac- 



owing to their having imparted all their juices to the wood, count of the 



,. f , , . ° ^ ^ , ^ ,1-1 . plant that occa- 



which changed it to a fungus, and not to a powder, like rot- f,ons thg dry 



tennefs from length of time. ^otj 



The Boletus Lachrymans is of the fungus tribe, and Is one of 



the few that have leaves, as the mifeltoe, &c. 



Nothing Is more eafy than to prevent the damage from the 



plant. Befides what I faid yefleiday, I am pofitive that a tile 



laid 



