412 OBSERVATIONS ON THE DISEASES, iScC. 



away, finishing off the edges as thin as possible : 

 then take a quantity of dry powder of Avood-ashes 

 mixed with a sixth part of the same quantity of the 

 ashes of burnt bones ; put it into a tin box, with 

 holes in the top, and shake the powder on the sur- 

 face of the plaster, till the whole is covered over 

 with it, letting it remain for half an hour, to absorb 

 the moisture ; then apply more powder, rubbing it 

 on gently with the hand, and repeating the appH- 

 cation of the powder till the whole plaster becomes 

 a dry smooth surface. 



All trees cut down near the ground should have 

 the surface made quite smooth, rounding it off in 

 a small degree, as before mentioned ; and the dry 

 powder directed to be used afterwards should have 

 an equal quantity of powder of alabaster mixed 

 with it, in order the better to resist the dripping of 

 trees and heavy rains. 



If any of the Composition be left for a future 

 occasion, it should be kept in a tub, or other ves- 

 sel, and urine of any kind poured on it, so as to 

 cover the surface ; otherwise the atmosphere will 

 greatly hurt the efficacy of the application. 



Where lime-rubbish of old buildings cannot be 

 easily got, take pounded chalk, or common lime, 

 after having been slaked, a month at least. 



As the growth of the tree will gradually aflect 

 the plaster, by raising up its edges next the 

 bark, care should be taken, where that happens, 

 to rub it over with the finger when occasion may 

 require (which is best done when moistened by 



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