Aug. 1, 1865.] THE TECHNOLOGIST. 
THE DUBLIN INTERNATIONAL EXHIBITION. 37 
Royal University of Naples, extracted from the green and mature 
leaves, from the unripe and ripe olive. Mannite exists in different 
proportions in every part of the olive tree ; the leaves, flowers, and 
fruit containing the greatest quantity ; the roots, wood, bark, and 
branches rather less. This saccharine principle is not always found in 
the same quantity at all stages of vegetation. At the period of 
blossoming, it accumulates in the flowers and diminishes in the leaves, 
the fallen flowers having once completed the phenomena of fecunda- 
tion, no longer contain any mannite ; it has likewise been found 
impossible, to obtain the slightest traces of it in the yellow fallen 
leaves. Mannite exists in the fruit as long as it continues green, 
diminishing in proportion as it ripens, and disappearing entirely when 
it becomes perfectly ripe, and contains the greatest quantity of oil. 
The leaves, with which the olive tree is always covered, and which it 
is reasonable to suppose must fulfil some important function, are never 
devoid of more or less mannite as long as they continue green, and as 
soon as they begin to turn yellow, o f hers have already taken their 
place, and would appear to accumulate, s-: to speak, the materials elabo- 
rated by their predecessors, and assume their functions. Many other 
substances are found in the leaves of the olive tree besides mannite. 
There are colouring matters, and especially the chlorophyl, which 
accompanies the mannite and follows its changes ; saccharine principles, 
which have the property of facilitating fermentation in contact with 
yeast, as also of reducing tartrate of potassa and copper ; organic acids 
and other matters not well-defined. The leaves of the olive tree, which 
have the property of accumulating mineral substances, contain a large 
quantity of water, varying according the period of vegetation, and 
sometimes amounting to 50 per cent. 
Honey and honeycomb is shown by Bartolomeo Bottamini : the 
following is the method of rearing bees pursued by the exhibitor in 
the Alpine Valleys of Bormio : — 
" The bees are placed in wooden hives about a foot wide, and rather 
more than three feet long, perfectly closed in front and rear, except that 
in the former case a small aperture is left at the bottom, three inches 
long and 1*3 inch in height. 
" Great care is necessary at the commencement of the spring to pro- 
vide sufficient food for the insects, and if they cannot procure it for 
themselves, two or three ounces of honey are placed in each hive. 
" As soon as the mountains become covered with flowers, the bees 
are smoked out of the hives, by burning a roll of linen rags at the back 
part, so as to drive them towards the front aperture. The old honey, 
being invariably of inferior quality, is then removed, taking care not to 
interrupt the workers, which have begun to make the pure new honey, 
and even after this operation the bees should not be deprived of honey 
in case of bad weather intervening, when they must be artificially fed 
as mentioned above. 
