t 449 3 
XXIX. A further Account oj the Ufefulnefs of wajhing the 
Stems of Trees. By Mr. Robert Marfham, of Stratton, 
F. R. S. 
Read May 31, 1781. 
T HE following account is a kind of poftfcript to my 
letter to Dr. moss, Lord Bifhop of Bath and' Wells, in 
1775, which the Royal Society did me the honour to publilh 
in the Philofophical Tranfadtions in 1 777. In that I {hewed 
how much a Beech increafed upon its hem being cleaned and 
wafhed * ; and in this I {hall {hew, that the benefit of cleaning 
the Rem continues feveral years : for the Beech which I wafhed 
in i 775 has increafed in the five years fince the wafhing eight 
inches and fix-tenths, or above an inch" arid feven-tenths yearly ; 
and the aggregate of nine unwafhed Beeches of the fame age 
does not amount to one inch and three-tenths yearly to each 
tree. In 1776 I wafhed another Beech (of the fame age, viz. 
feed in 1741) ; and the increafe in four years fince the wa filing 
is nine inches and two-tenths, or two inches and three-tenths 
yearly, when the aggregate of nine unwafhed Beeches amounted 
to but one inch and three-tenths and a half. In 1776 I wafhed 
an Oak which I planted in 1720, which has increafed in the 
four years fince wafhing feven inches and two-tenths, and the 
* Vide Phil. Tranf. vol. LXVII. for the ye^r 1777, parti, p. 1 2 . 
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aggre- 
