186 ROOT-CLIMBERS. Cuap. V. 
are made to press lightly on slips of glass, they emit 
after about a week’s interval, as I observed several 
times, minute drops of clear fluid, not in the least 
milky like that exuded from a wound. This fluid 
is slightly viscid, but cannot be drawn out into 
threads. It has the remarkable property of not soon 
drying; adrop, about the size of half a pin’s head, was 
slightly spread out on glass, and I scattered on it some 
minute grains of sand. The glass was left exposed 
in a drawer during hot and dry weather, and if the 
fluid had been water, it would certainly have dried 
in a few minutes; but it remained fluid, closely 
surrounding each grain of sand, during 128 days: how 
much longer it would have remained I cannot say. 
Some other rootlets were left in contact with the glass 
for about ten days or a fortnight, and the drops of 
secreted fluid were now rather larger, and so viscid 
that they could be drawn out into threads. Some 
other rootlets were left in contact during twenty-three 
days, and these were firmly cemented to the glass. 
Hence we may conclude that the rootlets first secrete 
a slightly viscid fluid, subsequently absorb the watery 
parts, (for we have seen that the fluid will not dry 
by itself,) and ultimately leave a cement. When the 
rootlets were torn from the glass, atoms of yellowish 
matter were left on it, which were partly dissolved 
by a drop of bisulphide of carbon ; and this extremely 
volatile fluid was rendered very much less volatile by 
what it had dissolved. 
As the bisulphide of carbon has a strong power 
