J86 THE EABMER’s MANCALi 
ly on certain vegetables, and even on some of their 
parts to the exclusion of others. The only objection 
to tiiis theory (and I must acknowledge, that the ex- 
perience of the most able Naturalists is against me,) 
is, that the dew is attracted by some bodies, whilst it 
is not by others ; but it is known that this phenome- 
non which often rises from the earth, always floats in 
the air, where it always obeys the least breath, and 
the weakest attraction, and often attaches itself to 
the upper as well as th^ lower parts of the leaves of 
trees. If It fell like rime, it would moisten indifie- 
rently every object. The acceleration of its fall, 
would enable it to surmount the obstacle of the weak 
repulsions, which it would find in its course- The 
circumstance, however, that favours in the greatest 
degree the illusion of the pretended fall of the honey- 
dew is, that it is only the upper part of the leaves 
which is moistened with it. It has been seen, also, 
that the moisture appears only on certain leaves, that 
is, on the new ones and those that are the least ex- 
jtosed, and this attraction or attachment is not the ef- 
fect of chance ; it is further known, that it is on the 
side of the leaf where the pores are not open and dis- 
linguishahle that the greatest exudation takes place. 
It is there that the excretory vessels unite, by which 
the humour of the plants escapes in the same manner 
as the absorbents, which serve for their nutrition, in 
Attracting the water of the rain and vapours which 
are diffused in the air. If the different proofs be now 
collected, which have been advanced, it may be con- 
sidered as undeniably proved, that the honey-dew ex- 
udes from the leaves of certain trees, and does not fall 
from the atmosphere. 
CHAP. XV. 
Oft Szvarmt in general. 
1m the spring, when a hive is over stocked with 
young Bees, a particular period arrives when they 
