176 Mr. Knight on the Origin and Formation of Roots. 
have not observed the same mortality to occur, in any degre- 
in the roots of trees when growing, under favourable circum - 
stances, in their natural situation. 
I am prepared to offer some observations on the causes 
which direct the roots of plants in search of proper nutriment 
and which occasion the root of the same plant to assume d - 
ferent forms under different circumstances ; but I propose to 
make those observations the subject of a future communica- 
tion. 
I am, my dear Sir, 
with great respect, 
your much obliged, & c. &c. 
THOMAS AND. KNIGHT. 
Elton., Dee, 22, 1808. 
