278 ^Treatise on 
cc Trees are like to green Thorns, the Flowers red* 
<c and they bear no Fruit.” The Manna of which 
Serapio here fpeaks, is perhaps not different from 
that which Avicenna has above told us is gathered 
from the Alhagi. I pafs over the other Arabians , 
from whofe Writings few certain Inferences can be 
drawn concerning the Nature and different Sorts of 
Mama , It is however very evident that this Juice, 
called Manna and aerial Honey , was known to them, 
as well as to the Latins and the Greeks. 
Two Queflions here offer themfelves to our Con- 
fideration (viz.) 1. Whether that Honey-Dew, fuch 
as the Ancients imagined it, did ever really exift ? 
2. Whether our Manna falls down like Dew upon 
Trees and Plants, or be produced within them ? 
As to the Hrft Queftion, I muft indeed ingenu- 
oufly confefs that this Dew is entirely unknown to 
me ; and, in my Opinion, no fuch is ever obferv- 
ed to defcend either upon Flowers, Leaves, or 
Stones. The fweet Juice which is found in many 
Flowers, derives its Origin from the interior Organs 
of the Plant. The Juice which is fometimes per- 
ceived upon Leaves, whether liquid or concreted, 
hath either ouzed out of the Pores of the Leaves, 
or hath diftilled from the Leaves of other Trees. 
In fine, if Stones fometimes appear fprinkled as it 
were with Drops of a fweet Liquor, it hath not fall- 
en upon them from the Heavens, but from the 
Leaves of fome neighbouring Trees, or by fome 
other Means hath been brought to them. Bodteus 
a Stapel , in his Notes upon Lh'ecphraftus’ s Hiftory 
of Plants, gives us an Account of an excellent Man- 
na, extremely white, and as fweet as Sugar, which 
was found upon Willow-trees, upon Stones, and 
upon the Earth ; where it had been depofited by an 
innumerable Swarm of large Flies in fo great Plenty, 
that from the Number of Drops falling from a 
Willow- 
