USEFUL PROJECTS. 



'8(S5 



footed earth to the depth of two 

 foot, and to fill up that space with 

 anchor-smiths' ashes, or a,shos from 

 a fouiidery, before his flooring 

 boards were laid. On the 15th of 

 May 1794, which was upwards of 

 six years after the flooring was laid, 

 as above mentioned, a minute exa- 

 mination of the boards, wainscot, 

 and timbers was made in the pre- 

 sence of a committee of the society 

 for the encouragement of arts &c. 

 and they were all found entirely 

 free from any appuarance of the rot. 

 To investigate the matter more 

 fully, a farther enquiry has been 

 made in June, 1803, and an answer 

 received, that there has been yet 

 uo appearance of the dry rot there ; 

 the society, tlierefore, think it may 

 be of consequence to notice the 

 fact, and have inserted, in the last 

 volume, some other papers with 

 which they have been favoured upon 

 the subject. They contain many 

 hints deserving public attention, 

 and which will doubtless tend to 

 check the progress of this evil. 



Mr. Johnston's conimunicntion. 



Some time between 1771 .ind 

 1773, I went, at the request of a 

 friend, to the chapel at the Lock 

 hospital, through curiosity, to exa- 

 mine a pew there, that had frequcnt- 

 \y been repaired for damages by the 

 dry rot. 



After a close investigation, we 

 found that it was the operation of a 

 plant, wliosc leaf resembled that 

 of the vine. Wherever it had 

 touched, the cfl'ect of its poisonous 

 quality got througli the wood to the 

 paint, which 1 liave seen a mere 

 bkin. 1 j)roposed to cover the floor 

 with bricks laid in mortar, which 

 -was accordingly done. I callid 

 twice since, the last lime about seven 



Vou XLVU. 



years ago ; and have reason to 

 think that it had never appeared 

 again. 



The next opportunity of examin- 

 ing it carefully was at Mark ' Hall, 

 in Essex, the seat of Mr. Montague 

 Burgoyne. In a parlour there were 

 three pillars of about ten inches in 

 diameter, the out wood of which 

 was between two and three inches 

 thick. 



Two of them were eaten through 

 in loss than seven years, from tha 

 basis about two feet upward, within 

 the hollow, and were as rotten as if 

 it had been the eifoct of a hundred 

 years standing. Mr. Montague 

 Burgoyne's gardener was a botanist: 

 he found the plant where I directed 

 him to search for it; and he said it 

 was the boletus lachrymans. 



At another time, I saw it in a 

 house at White Hall, built by sir 

 John Vanburgh, whose nephew then 

 lived in it. The house is, I think, 

 only two stories high; the plant had 

 ascended to the upper story, com- 

 mitting devastation on the wainscot 

 all the way. It will destroy hall- 

 iuch deal wainscoting in a year. 



I have had it twice in houses I 

 inhabited, one in Suflolk, and the 

 other in Gloucestershire. I bore 

 with the first; in the other case, I 

 undertook, and did slop it ef- 

 fectually. 



The cause is from the floor being 

 laid on the earth, which has been, 

 where I have observed, of a gravelly 

 or sandy loam, 'ihc moisture from 

 a water course at hand, or a north 

 aspect, where the outer wall stands 

 in a garden bed, so that the rain 

 jiercolales, arc groat cnconragers ; 

 it requires moisture. 



[t never rises in the middle of the 



floor ; because, it the seed were 



there, it could not germinate for 



3 K wat^'- 



